suggestions from code review

## Summary

Removes the `module_ptr` field from `AstNodeRef` in release mode, and
change `NodeIndex` to a `NonZeroU32` to reduce the size of
`Option<AstNodeRef<_>>` fields.

I believe CI runs in debug mode, so this won't show up in the memory
report, but this reduces memory by ~2% in release mode.

Cargo.lock

@@ -260,6 +260,9 @@ name = "bitflags"
 version = "2.9.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6a65b545ab31d687cff52899d4890855fec459eb6afe0da6417b8a18da87aa29"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "bitvec"
@@ -1028,6 +1031,16 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
 
+[[package]]
+name = "erased-serde"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e004d887f51fcb9fef17317a2f3525c887d8aa3f4f50fed920816a688284a5b7"
+dependencies = [
+ "serde",
+ "typeid",
+]
+
 [[package]]
 name = "errno"
 version = "0.3.13"
@@ -3451,12 +3464,13 @@ checksum = "28d3b2b1366ec20994f1fd18c3c594f05c5dd4bc44d8bb0c1c632c8d6829481f"
 [[package]]
 name = "salsa"
 version = "0.23.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=a3ffa22cb26756473d56f867aedec3fd907c4dd9#a3ffa22cb26756473d56f867aedec3fd907c4dd9"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=a0e7a06#a0e7a0660c93136f23bf08b4f1604eee3d1f6b11"
 dependencies = [
  "boxcar",
  "compact_str",
  "crossbeam-queue",
  "crossbeam-utils",
+ "erased-serde",
  "hashbrown 0.15.5",
  "hashlink",
  "indexmap",
@@ -3467,6 +3481,7 @@ dependencies = [
  "rustc-hash",
  "salsa-macro-rules",
  "salsa-macros",
+ "serde",
  "smallvec",
  "thin-vec",
  "tracing",
@@ -3475,12 +3490,12 @@ dependencies = [
 [[package]]
 name = "salsa-macro-rules"
 version = "0.23.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=a3ffa22cb26756473d56f867aedec3fd907c4dd9#a3ffa22cb26756473d56f867aedec3fd907c4dd9"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=a0e7a06#a0e7a0660c93136f23bf08b4f1604eee3d1f6b11"
 
 [[package]]
 name = "salsa-macros"
 version = "0.23.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=a3ffa22cb26756473d56f867aedec3fd907c4dd9#a3ffa22cb26756473d56f867aedec3fd907c4dd9"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=a0e7a06#a0e7a0660c93136f23bf08b4f1604eee3d1f6b11"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3700,6 +3715,9 @@ name = "smallvec"
 version = "1.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "snapbox"
@@ -3904,6 +3922,9 @@ name = "thin-vec"
 version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "144f754d318415ac792f9d69fc87abbbfc043ce2ef041c60f16ad828f638717d"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "thiserror"
@@ -4261,6 +4282,7 @@ name = "ty_project"
 version = "0.0.0"
 dependencies = [
  "anyhow",
+ "bincode 2.0.1",
  "camino",
  "colored 3.0.0",
  "crossbeam",
@@ -4290,6 +4312,7 @@ dependencies = [
  "tracing",
  "ty_combine",
  "ty_python_semantic",
+ "ty_static",
  "ty_vendored",
 ]
 
@@ -4461,6 +4484,12 @@ version = "2.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6af6ae20167a9ece4bcb41af5b80f8a1f1df981f6391189ce00fd257af04126a"
 
+[[package]]
+name = "typeid"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc7d623258602320d5c55d1bc22793b57daff0ec7efc270ea7d55ce1d5f5471c"
+
 [[package]]
 name = "typenum"
 version = "1.18.0"

Cargo.toml

@@ -57,8 +57,8 @@ anyhow = { version = "1.0.80" }
 arc-swap = { version = "1.7.1" }
 assert_fs = { version = "1.1.0" }
 argfile = { version = "0.2.0" }
-bincode = { version = "2.0.0" }
-bitflags = { version = "2.5.0" }
+bincode = { version = "2.0.0", features = ["serde"] }
+bitflags = { version = "2.5.0", features = ["serde"] }
 bitvec = { version = "1.0.1", default-features = false, features = [
     "alloc",
 ] }
@@ -126,7 +126,7 @@ memchr = { version = "2.7.1" }
 mimalloc = { version = "0.1.39" }
 natord = { version = "1.0.9" }
 notify = { version = "8.0.0" }
-ordermap = { version = "0.5.0" }
+ordermap = { version = "0.5.0", features = ["serde"] }
 path-absolutize = { version = "3.1.1" }
 path-slash = { version = "0.2.1" }
 pathdiff = { version = "0.2.1" }
@@ -143,24 +143,25 @@ regex-automata = { version = "0.4.9" }
 rustc-hash = { version = "2.0.0" }
 rustc-stable-hash = { version = "0.1.2" }
 # When updating salsa, make sure to also update the revision in `fuzz/Cargo.toml`
-salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "a3ffa22cb26756473d56f867aedec3fd907c4dd9", default-features = false, features = [
+salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "a0e7a06", default-features = false, features = [
     "compact_str",
     "macros",
     "salsa_unstable",
     "inventory",
+    "persistence",
 ] }
 schemars = { version = "0.8.16" }
 seahash = { version = "4.1.0" }
-serde = { version = "1.0.197", features = ["derive"] }
+serde = { version = "1.0.197", features = ["derive", "rc"] }
 serde-wasm-bindgen = { version = "0.6.4" }
-serde_json = { version = "1.0.113" }
+serde_json = { version = "1.0.142" }
 serde_test = { version = "1.0.152" }
 serde_with = { version = "3.6.0", default-features = false, features = [
     "macros",
 ] }
 shellexpand = { version = "3.0.0" }
 similar = { version = "2.4.0", features = ["inline"] }
-smallvec = { version = "1.13.2", features = ["union", "const_generics", "const_new"] }
+smallvec = { version = "1.13.2", features = ["union", "const_generics", "const_new", "serde"] }
 snapbox = { version = "0.6.0", features = [
     "diff",
     "term-svg",
@@ -215,6 +216,8 @@ unexpected_cfgs = { level = "warn", check-cfg = [
 
 [workspace.lints.clippy]
 pedantic = { level = "warn", priority = -2 }
+# Enabled at the crate level
+disallowed_methods = "allow"
 # Allowed pedantic lints
 char_lit_as_u8 = "allow"
 collapsible_else_if = "allow"
@@ -253,6 +256,7 @@ unused_peekable = "warn"
 # Diagnostics are not actionable: Enable once https://github.com/rust-lang/rust-clippy/issues/13774 is resolved.
 large_stack_arrays = "allow"
 
+
 [profile.release]
 # Note that we set these explicitly, and these values
 # were chosen based on a trade-off between compile times

clippy.toml

@@ -24,3 +24,20 @@ ignore-interior-mutability = [
     # The expression is read-only.
     "ruff_python_ast::hashable::HashableExpr",
 ]
+
+disallowed-methods = [
+    { path = "std::env::var", reason = "Use System::env_var instead in ty crates" },
+    { path = "std::env::current_dir", reason = "Use System::current_directory instead in ty crates" },
+    { path = "std::fs::read_to_string", reason = "Use System::read_to_string instead in ty crates" },
+    { path = "std::fs::metadata", reason = "Use System::path_metadata instead in ty crates" },
+    { path = "std::fs::canonicalize", reason = "Use System::canonicalize_path instead in ty crates" },
+    { path = "dunce::canonicalize", reason = "Use System::canonicalize_path instead in ty crates" },
+    { path = "std::fs::read_dir", reason = "Use System::read_directory instead in ty crates" },
+    { path = "std::fs::write", reason = "Use WritableSystem::write_file instead in ty crates" },
+    { path = "std::fs::create_dir_all", reason = "Use WritableSystem::create_directory_all instead in ty crates" },
+    { path = "std::fs::File::create_new", reason = "Use WritableSystem::create_new_file instead in ty crates" },
+    # Path methods that have System trait equivalents
+    { path = "std::path::Path::exists", reason = "Use System::path_exists instead in ty crates" },
+    { path = "std::path::Path::is_dir", reason = "Use System::is_directory instead in ty crates" },
+    { path = "std::path::Path::is_file", reason = "Use System::is_file instead in ty crates" },
+]

crates/ruff/Cargo.toml

@@ -31,7 +31,7 @@ ruff_workspace = { workspace = true }
 
 anyhow = { workspace = true }
 argfile = { workspace = true }
-bincode = { workspace = true, features = ["serde"] }
+bincode = { workspace = true }
 bitflags = { workspace = true }
 cachedir = { workspace = true }
 clap = { workspace = true, features = ["derive", "env", "wrap_help"] }

crates/ruff_db/src/diagnostic/mod.rs

@@ -22,6 +22,7 @@ mod stylesheet;
 /// a characteristic is a deficiency. An example of a characteristic that is
 /// _not_ a deficiency is the `reveal_type` diagnostic for our type checker.
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct Diagnostic {
     /// The actual diagnostic.
     ///
@@ -500,6 +501,7 @@ impl Diagnostic {
 }
 
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 struct DiagnosticInner {
     id: DiagnosticId,
     severity: Severity,
@@ -576,6 +578,7 @@ impl Eq for RenderingSortKey<'_> {}
 /// another (for a single parent diagnostic) is the order in which they were
 /// attached to the diagnostic.
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct SubDiagnostic {
     /// Like with `Diagnostic`, we box the `SubDiagnostic` to make it
     /// pointer-sized.
@@ -685,6 +688,7 @@ impl SubDiagnostic {
 }
 
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 struct SubDiagnosticInner {
     severity: SubDiagnosticSeverity,
     message: DiagnosticMessage,
@@ -713,6 +717,7 @@ struct SubDiagnosticInner {
 /// Messages attached to annotations should also be as brief and specific as
 /// possible. Long messages could negative impact the quality of rendering.
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct Annotation {
     /// The span of this annotation, corresponding to some subsequence of the
     /// user's input that we want to highlight.
@@ -855,6 +860,7 @@ impl Annotation {
 /// These tags are used to provide additional information about the annotation.
 /// and are passed through to the language server protocol.
 #[derive(Debug, Clone, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub enum DiagnosticTag {
     /// Unused or unnecessary code. Used for unused parameters, unreachable code, etc.
     Unnecessary,
@@ -869,6 +875,7 @@ pub enum DiagnosticTag {
 ///
 /// Rules use kebab case, e.g. `no-foo`.
 #[derive(Debug, Copy, Clone, PartialOrd, Ord, PartialEq, Eq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize), serde(transparent))]
 pub struct LintName(&'static str);
 
 impl LintName {
@@ -881,6 +888,66 @@ impl LintName {
     }
 }
 
+#[cfg(feature = "serde")]
+pub use lint_name_serde::LintRegistryGuard;
+
+#[cfg(feature = "serde")]
+mod lint_name_serde {
+    use super::LintName;
+
+    use std::cell::RefCell;
+
+    thread_local! {
+        /// Serde doesn't provide any easy means to pass a value to a [`Deserialize`] implementation,
+        /// but we need a way to retrieve static [`LintName`]s from the lint registry when deserializing.
+        ///
+        /// Use the [`LintRegistryGuard`] to initialize the thread local before calling into any
+        /// deserialization code. It ensures that the thread local variable gets cleaned up
+        /// once deserialization is done (once the guard gets dropped).
+        static LINT_REGISTRY: RefCell<Option<LintRegistry>> = const { RefCell::new(None) };
+    }
+
+    type LintRegistry = fn(&str) -> Option<LintName>;
+
+    /// Guard to safely change the lint registry for the current thread.
+    #[must_use]
+    pub struct LintRegistryGuard {
+        prev_value: Option<LintRegistry>,
+    }
+
+    impl LintRegistryGuard {
+        pub fn new(registry: LintRegistry) -> Self {
+            let prev = LINT_REGISTRY.replace(Some(registry));
+            Self { prev_value: prev }
+        }
+    }
+
+    impl Drop for LintRegistryGuard {
+        fn drop(&mut self) {
+            LINT_REGISTRY.set(self.prev_value.take());
+        }
+    }
+
+    #[cfg(feature = "serde")]
+    impl<'de> serde::Deserialize<'de> for LintName {
+        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+        where
+            D: serde::Deserializer<'de>,
+        {
+            let name: &str = serde::Deserialize::deserialize(deserializer)?;
+
+            LINT_REGISTRY.with_borrow(|registry| {
+                let registry = registry
+                    .expect("must set the `LintRegistryGuard` when deserializing a `LintName`");
+
+                registry(name).ok_or(serde::de::Error::custom(format!(
+                    "invalid `LintName` {name}"
+                )))
+            })
+        }
+    }
+}
+
 impl std::ops::Deref for LintName {
     type Target = str;
 
@@ -909,6 +976,7 @@ impl PartialEq<&str> for LintName {
 
 /// Uniquely identifies the kind of a diagnostic.
 #[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub enum DiagnosticId {
     Panic,
 
@@ -1097,6 +1165,30 @@ impl UnifiedFile {
     }
 }
 
+#[cfg(feature = "serde")]
+impl serde::Serialize for UnifiedFile {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            UnifiedFile::Ty(file) => serde::Serialize::serialize(file, serializer),
+            // Persistent caching is only used in ty.
+            UnifiedFile::Ruff(..) => panic!("Ruff files are not persistable"),
+        }
+    }
+}
+
+#[cfg(feature = "serde")]
+impl<'de> serde::Deserialize<'de> for UnifiedFile {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        serde::Deserialize::deserialize(deserializer).map(UnifiedFile::Ty)
+    }
+}
+
 /// A unified wrapper for types that can be converted to a [`SourceCode`].
 ///
 /// As with [`UnifiedFile`], ruff and ty use slightly different representations for source code.
@@ -1128,6 +1220,7 @@ impl DiagnosticSource {
 /// range isn't present, it semantically implies that the diagnostic refers to
 /// the entire file. For example, when the file should be executable but isn't.
 #[derive(Debug, Clone, PartialEq, Eq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct Span {
     file: UnifiedFile,
     range: Option<TextRange>,
@@ -1206,6 +1299,7 @@ impl From<crate::files::FileRange> for Span {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Ord, PartialOrd, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub enum Severity {
     Info,
     Warning,
@@ -1241,6 +1335,7 @@ impl Severity {
 /// used for main diagnostics. If we want to add `Severity::Help` in the future, this type could be
 /// deleted and the two combined again.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Ord, PartialOrd, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub enum SubDiagnosticSeverity {
     Help,
     Info,
@@ -1489,6 +1584,7 @@ impl std::fmt::Display for ConciseMessage<'_> {
 /// a blanket trait implementation for `IntoDiagnosticMessage` for
 /// anything that implements `std::fmt::Display`.
 #[derive(Clone, Debug, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct DiagnosticMessage(Box<str>);
 
 impl DiagnosticMessage {
@@ -1552,7 +1648,11 @@ impl<T: std::fmt::Display> IntoDiagnosticMessage for T {
 ///
 /// For Ruff rules this means the noqa code.
 #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Default, Hash, get_size2::GetSize)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize), serde(transparent))]
+#[cfg_attr(
+    feature = "serde",
+    derive(serde::Serialize, serde::Deserialize),
+    serde(transparent)
+)]
 pub struct SecondaryCode(String);
 
 impl SecondaryCode {

crates/ruff_db/src/file_revision.rs

@@ -9,7 +9,17 @@ use crate::system::file_time_now;
 /// * The last modification time of the file.
 /// * The hash of the file's content.
 /// * The revision as it comes from an external system, for example the LSP.
-#[derive(Copy, Clone, Debug, Eq, PartialEq, Default, get_size2::GetSize)]
+#[derive(
+    Copy,
+    Clone,
+    Debug,
+    Eq,
+    PartialEq,
+    Default,
+    get_size2::GetSize,
+    serde::Serialize,
+    serde::Deserialize,
+)]
 pub struct FileRevision(u128);
 
 impl FileRevision {

crates/ruff_db/src/files.rs

@@ -14,7 +14,7 @@ use crate::diagnostic::{Span, UnifiedFile};
 use crate::file_revision::FileRevision;
 use crate::files::file_root::FileRoots;
 use crate::files::private::FileStatus;
-use crate::system::{SystemPath, SystemPathBuf, SystemVirtualPath, SystemVirtualPathBuf};
+use crate::system::{FileType, SystemPath, SystemPathBuf, SystemVirtualPath, SystemVirtualPathBuf};
 use crate::vendored::{VendoredPath, VendoredPathBuf};
 use crate::{Db, FxDashMap, vendored};
 
@@ -139,6 +139,7 @@ impl Files {
                 };
 
                 tracing::trace!("Adding vendored file `{}`", path);
+
                 let file = File::builder(FilePath::Vendored(path.to_path_buf()))
                     .permissions(Some(0o444))
                     .revision(metadata.revision())
@@ -200,7 +201,15 @@ impl Files {
         let mut roots = self.inner.roots.write().unwrap();
 
         let absolute = SystemPath::absolute(path, db.system().current_directory());
-        roots.try_add(db, absolute, kind)
+
+        let (Ok(root) | Err(root)) = roots.try_add(db, absolute, |absolute| {
+            FileRoot::builder(absolute, kind, FileRevision::now())
+                .durability(Durability::HIGH)
+                .revision_durability(kind.durability())
+                .new(db)
+        });
+
+        root
     }
 
     /// Updates the revision of the root for `path`.
@@ -259,6 +268,51 @@ impl Files {
             root.set_revision(db).to(FileRevision::now());
         }
     }
+
+    /// Seed the files with an existing [`File`] instance.
+    pub fn seed(&self, file: File, db: &dyn Db) {
+        let seeded = match file.path(db) {
+            FilePath::System(path) => self
+                .inner
+                .system_by_path
+                .insert(path.clone(), file)
+                .is_none(),
+            FilePath::SystemVirtual(path) => self
+                .inner
+                .system_virtual_by_path
+                .insert(path.clone(), VirtualFile(file))
+                .is_none(),
+            FilePath::Vendored(path) => self
+                .inner
+                .vendored_by_path
+                .insert(path.clone(), file)
+                .is_none(),
+        };
+
+        // Recreating a `File` input means the persisted queries depending on that file
+        // will be invalidated.
+        assert!(
+            seeded,
+            "unexpected `File` input recreated for path `{}`",
+            file.path(db)
+        );
+    }
+
+    /// Seed the files with an existing [`FileRoot`] instance.
+    pub fn seed_root(&self, root: FileRoot, db: &dyn Db) {
+        let mut roots = self.inner.roots.write().unwrap();
+        let seeded = roots
+            .try_add(db, root.path(db).to_path_buf(), |_| root)
+            .is_ok();
+
+        // Recreating a `FileRoot` input means the persisted queries depending on that file
+        // root will be invalidated.
+        assert!(
+            seeded,
+            "unexpected `FileRoot` input recreated for path `{}`",
+            root.path(db)
+        );
+    }
 }
 
 impl fmt::Debug for Files {
@@ -290,7 +344,7 @@ impl std::panic::RefUnwindSafe for Files {}
 /// # Ordering
 /// Ordering is based on the file's salsa-assigned id and not on its values.
 /// The id may change between runs.
-#[salsa::input(heap_size=ruff_memory_usage::heap_size)]
+#[salsa::input(persist, heap_size=ruff_memory_usage::heap_size)]
 #[derive(PartialOrd, Ord)]
 pub struct File {
     /// The path of the file (immutable).
@@ -414,6 +468,15 @@ impl File {
         }
     }
 
+    /// Loads all existing [`File`]s in the database.
+    pub fn load_all(db: &dyn Db) -> Vec<File> {
+        // TODO: Prune deleted paths.
+        File::ingredient(db)
+            .entries(db.zalsa())
+            .map(|entry| entry.as_struct())
+            .collect()
+    }
+
     /// Private method providing the implementation for [`Self::sync_path`] and [`Self::sync`] for
     /// system paths.
     fn sync_system_path(db: &mut dyn Db, path: &SystemPath, file: Option<File>) {
@@ -522,7 +585,17 @@ impl VirtualFile {
 // The types in here need to be public because they're salsa ingredients but we
 // don't want them to be publicly accessible. That's why we put them into a private module.
 mod private {
-    #[derive(Copy, Clone, Debug, Eq, PartialEq, Default, get_size2::GetSize)]
+    #[derive(
+        Copy,
+        Clone,
+        Debug,
+        Eq,
+        PartialEq,
+        Default,
+        get_size2::GetSize,
+        serde::Serialize,
+        serde::Deserialize,
+    )]
     pub enum FileStatus {
         /// The file exists.
         #[default]
@@ -536,6 +609,16 @@ mod private {
     }
 }
 
+impl From<FileType> for FileStatus {
+    fn from(value: FileType) -> Self {
+        match value {
+            FileType::File => FileStatus::Exists,
+            FileType::Symlink => FileStatus::Exists,
+            FileType::Directory => FileStatus::IsADirectory,
+        }
+    }
+}
+
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum FileError {
     IsADirectory,

crates/ruff_db/src/files/file_root.rs

@@ -16,7 +16,7 @@ use crate::system::{SystemPath, SystemPathBuf};
 /// The main usage of file roots is to determine a file's durability. But it can also be used
 /// to make a salsa query dependent on whether a file in a root has changed without writing any
 /// manual invalidation logic.
-#[salsa::input(debug, heap_size=ruff_memory_usage::heap_size)]
+#[salsa::input(persist, debug, heap_size=ruff_memory_usage::heap_size)]
 pub struct FileRoot {
     /// The path of a root is guaranteed to never change.
     #[returns(deref)]
@@ -35,9 +35,20 @@ impl FileRoot {
     pub fn durability(self, db: &dyn Db) -> salsa::Durability {
         self.kind_at_time_of_creation(db).durability()
     }
+
+    /// Loads all existing [`FileRoot`]s in the database.
+    pub fn load_all(db: &dyn Db) -> Vec<FileRoot> {
+        // TODO: Prune deleted paths.
+        FileRoot::ingredient(db)
+            .entries(db.zalsa())
+            .map(|entry| entry.as_struct())
+            .collect()
+    }
 }
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq, get_size2::GetSize)]
+#[derive(
+    Copy, Clone, Debug, Eq, PartialEq, get_size2::GetSize, serde::Serialize, serde::Deserialize,
+)]
 pub enum FileRootKind {
     /// The root of a project.
     Project,
@@ -47,7 +58,7 @@ pub enum FileRootKind {
 }
 
 impl FileRootKind {
-    const fn durability(self) -> Durability {
+    pub const fn durability(self) -> Durability {
         match self {
             FileRootKind::Project => Durability::LOW,
             FileRootKind::LibrarySearchPath => Durability::HIGH,
@@ -62,34 +73,34 @@ pub(super) struct FileRoots {
 }
 
 impl FileRoots {
-    /// Tries to add a new root for `path` and returns the root.
+    /// Tries to add a new root for `path`.
     ///
     /// The root isn't added nor is the file root's kind updated if a root for `path` already exists.
+    ///
+    /// Returns `Ok(root)` if the `FileRoot` was successfully added, and returns `Err(root)` with
+    /// the previous root if one already existed at that path.
     pub(super) fn try_add(
         &mut self,
         db: &dyn Db,
         path: SystemPathBuf,
-        kind: FileRootKind,
-    ) -> FileRoot {
+        create_root: impl FnOnce(SystemPathBuf) -> FileRoot,
+    ) -> Result<FileRoot, FileRoot> {
         // SAFETY: Guaranteed to succeed because `path` is a UTF-8 that only contains Unicode characters.
         let normalized_path = path.as_std_path().to_slash().unwrap();
 
         if let Ok(existing) = self.by_path.at(&normalized_path) {
             // Only if it is an exact match
             if existing.value.path(db) == &*path {
-                return *existing.value;
+                return Err(*existing.value);
             }
         }
 
-        // normalize the path to use `/` separators and escape the '{' and '}' characters,
-        // which matchit uses for routing parameters
+        // Normalize the path to use `/` separators and escape the '{' and '}' characters,
+        // which `matchit` uses for routing parameters.
         let mut route = normalized_path.replace('{', "{{").replace('}', "}}");
 
         // Insert a new source root
-        let root = FileRoot::builder(path, kind, FileRevision::now())
-            .durability(Durability::HIGH)
-            .revision_durability(kind.durability())
-            .new(db);
+        let root = create_root(path);
 
         // Insert a path that matches the root itself
         self.by_path.insert(route.clone(), root).unwrap();
@@ -100,7 +111,7 @@ impl FileRoots {
         self.by_path.insert(route, root).unwrap();
         self.roots.push(root);
 
-        root
+        Ok(root)
     }
 
     /// Returns the closest root for `path` or `None` if no root contains `path`.

crates/ruff_db/src/files/path.rs

@@ -11,7 +11,9 @@ use std::fmt::{Display, Formatter};
 /// * a file stored on the [host system](crate::system::System).
 /// * a virtual file stored on the [host system](crate::system::System).
 /// * a vendored file stored in the [vendored file system](crate::vendored::VendoredFileSystem).
-#[derive(Clone, Debug, Eq, PartialEq, Hash, get_size2::GetSize)]
+#[derive(
+    Clone, Debug, Eq, PartialEq, Hash, get_size2::GetSize, serde::Serialize, serde::Deserialize,
+)]
 pub enum FilePath {
     /// Path to a file on the [host system](crate::system::System).
     System(SystemPathBuf),

crates/ruff_db/src/lib.rs

@@ -1,3 +1,8 @@
+#![warn(
+    clippy::disallowed_methods,
+    reason = "Prefer System trait methods over std methods"
+)]
+
 use crate::files::Files;
 use crate::system::System;
 use crate::vendored::VendoredFileSystem;
@@ -65,6 +70,10 @@ pub trait Db: salsa::Database {
 /// to process work in parallel. For example, to index a directory or checking the files of a project.
 /// ty can still spawn more threads for other tasks, e.g. to wait for a Ctrl+C signal or
 /// watching the files for changes.
+#[expect(
+    clippy::disallowed_methods,
+    reason = "We don't have access to System here, but this is also only used by the CLI and the server which always run on a real system."
+)]
 pub fn max_parallelism() -> NonZeroUsize {
     std::env::var(EnvVars::TY_MAX_PARALLELISM)
         .or_else(|_| std::env::var(EnvVars::RAYON_NUM_THREADS))

crates/ruff_db/src/parsed.rs

@@ -92,14 +92,14 @@ impl ParsedModule {
         self.inner.store(None);
     }
 
-    /// Returns a pointer for this [`ParsedModule`].
+    /// Returns the pointer address of this [`ParsedModule`].
     ///
     /// The pointer uniquely identifies the module within the current Salsa revision,
     /// regardless of whether particular [`ParsedModuleRef`] instances are garbage collected.
-    pub fn as_ptr(&self) -> *const () {
+    pub fn addr(&self) -> usize {
         // Note that the outer `Arc` in `inner` is stable across garbage collection, while the inner
         // `Arc` within the `ArcSwap` may change.
-        Arc::as_ptr(&self.inner).cast()
+        Arc::as_ptr(&self.inner).addr()
     }
 }
 
@@ -202,9 +202,13 @@ mod indexed {
 
         /// Returns the node at the given index.
         pub fn get_by_index<'ast>(&'ast self, index: NodeIndex) -> AnyRootNodeRef<'ast> {
+            let index = index
+                .as_u32()
+                .expect("attempted to access uninitialized `NodeIndex`");
+
             // Note that this method restores the correct lifetime: the nodes are valid for as
             // long as the reference to `IndexedModule` is alive.
-            self.index[index.as_usize()]
+            self.index[index as usize]
         }
     }
 
@@ -220,7 +224,7 @@ mod indexed {
             T: HasNodeIndex + std::fmt::Debug,
             AnyRootNodeRef<'a>: From<&'a T>,
         {
-            node.node_index().set(self.index);
+            node.node_index().set(NodeIndex::from(self.index));
             self.nodes.push(AnyRootNodeRef::from(node));
             self.index += 1;
         }

crates/ruff_db/src/source.rs

@@ -148,7 +148,16 @@ impl From<Notebook> for SourceTextKind {
     }
 }
 
-#[derive(Debug, thiserror::Error, PartialEq, Eq, Clone, get_size2::GetSize)]
+#[derive(
+    Debug,
+    thiserror::Error,
+    PartialEq,
+    Eq,
+    Clone,
+    get_size2::GetSize,
+    serde::Serialize,
+    serde::Deserialize,
+)]
 pub enum SourceTextError {
     #[error("Failed to read notebook: {0}`")]
     FailedToReadNotebook(String),

crates/ruff_db/src/system.rs

@@ -46,7 +46,7 @@ pub type Result<T> = std::io::Result<T>;
 ///    * File watching isn't supported.
 ///
 /// Abstracting the system also enables tests to use a more efficient in-memory file system.
-pub trait System: Debug {
+pub trait System: Debug + Sync + Send {
     /// Reads the metadata of the file or directory at `path`.
     ///
     /// This function will traverse symbolic links to query information about the destination file.
@@ -66,6 +66,9 @@ pub trait System: Debug {
     /// See [dunce::canonicalize] for more information.
     fn canonicalize_path(&self, path: &SystemPath) -> Result<SystemPathBuf>;
 
+    /// Reads the content of the file at `path` into a bytes buffer.
+    fn read_to_end(&self, path: &SystemPath) -> Result<Vec<u8>>;
+
     /// Reads the content of the file at `path` into a [`String`].
     fn read_to_string(&self, path: &SystemPath) -> Result<String>;
 
@@ -197,6 +200,8 @@ pub trait System: Debug {
     fn as_any(&self) -> &dyn std::any::Any;
 
     fn as_any_mut(&mut self) -> &mut dyn std::any::Any;
+
+    fn dyn_clone(&self) -> Box<dyn System>;
 }
 
 #[derive(Debug, Default, Copy, Clone, Eq, PartialEq)]
@@ -240,7 +245,7 @@ pub trait WritableSystem: System {
     fn create_new_file(&self, path: &SystemPath) -> Result<()>;
 
     /// Writes the given content to the file at the given path.
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()>;
+    fn write_file(&self, path: &SystemPath, content: &[u8]) -> Result<()>;
 
     /// Creates a directory at `path` as well as any intermediate directories.
     fn create_directory_all(&self, path: &SystemPath) -> Result<()>;
@@ -276,7 +281,7 @@ pub trait WritableSystem: System {
         // ensures that only one thread/process ever attempts to write to it to avoid corrupting
         // the cache.
         self.create_new_file(&cache_path)?;
-        self.write_file(&cache_path, &contents)?;
+        self.write_file(&cache_path, contents.as_bytes())?;
 
         Ok(Some(cache_path))
     }

crates/ruff_db/src/system/memory_fs.rs

@@ -114,8 +114,8 @@ impl MemoryFileSystem {
         matches!(by_path.get(&normalized), Some(Entry::Directory(_)))
     }
 
-    pub fn read_to_string(&self, path: impl AsRef<SystemPath>) -> Result<String> {
-        fn read_to_string(fs: &MemoryFileSystem, path: &SystemPath) -> Result<String> {
+    pub fn read_to_end(&self, path: impl AsRef<SystemPath>) -> Result<Vec<u8>> {
+        fn read_to_end(fs: &MemoryFileSystem, path: &SystemPath) -> Result<Vec<u8>> {
             let by_path = fs.inner.by_path.read().unwrap();
             let normalized = fs.normalize_path(path);
 
@@ -127,13 +127,18 @@ impl MemoryFileSystem {
             }
         }
 
-        read_to_string(self, path.as_ref())
+        read_to_end(self, path.as_ref())
     }
 
-    pub(crate) fn read_virtual_path_to_string(
+    pub fn read_to_string(&self, path: impl AsRef<SystemPath>) -> Result<String> {
+        self.read_to_end(path)
+            .and_then(|bytes| String::from_utf8(bytes).map_err(io::Error::other))
+    }
+
+    pub(crate) fn read_virtual_path_to_end(
         &self,
         path: impl AsRef<SystemVirtualPath>,
-    ) -> Result<String> {
+    ) -> Result<Vec<u8>> {
         let virtual_files = self.inner.virtual_files.read().unwrap();
         let file = virtual_files
             .get(&path.as_ref().to_path_buf())
@@ -142,6 +147,14 @@ impl MemoryFileSystem {
         Ok(file.content.clone())
     }
 
+    pub(crate) fn read_virtual_path_to_string(
+        &self,
+        path: impl AsRef<SystemVirtualPath>,
+    ) -> Result<String> {
+        self.read_virtual_path_to_end(path)
+            .and_then(|bytes| String::from_utf8(bytes).map_err(io::Error::other))
+    }
+
     pub fn exists(&self, path: &SystemPath) -> bool {
         let by_path = self.inner.by_path.read().unwrap();
         let normalized = self.normalize_path(path);
@@ -161,7 +174,7 @@ impl MemoryFileSystem {
         match by_path.entry(normalized) {
             btree_map::Entry::Vacant(entry) => {
                 entry.insert(Entry::File(File {
-                    content: String::new(),
+                    content: Vec::new(),
                     last_modified: file_time_now(),
                 }));
 
@@ -177,13 +190,17 @@ impl MemoryFileSystem {
     /// Stores a new file in the file system.
     ///
     /// The operation overrides the content for an existing file with the same normalized `path`.
-    pub fn write_file(&self, path: impl AsRef<SystemPath>, content: impl ToString) -> Result<()> {
+    pub fn write_file(
+        &self,
+        path: impl AsRef<SystemPath>,
+        content: impl Into<Vec<u8>>,
+    ) -> Result<()> {
         let mut by_path = self.inner.by_path.write().unwrap();
 
         let normalized = self.normalize_path(path.as_ref());
 
         let file = get_or_create_file(&mut by_path, &normalized)?;
-        file.content = content.to_string();
+        file.content = content.into();
         file.last_modified = file_time_now();
 
         Ok(())
@@ -214,7 +231,7 @@ impl MemoryFileSystem {
     pub fn write_file_all(
         &self,
         path: impl AsRef<SystemPath>,
-        content: impl ToString,
+        content: impl Into<Vec<u8>>,
     ) -> Result<()> {
         let path = path.as_ref();
 
@@ -228,19 +245,23 @@ impl MemoryFileSystem {
     /// Stores a new virtual file in the file system.
     ///
     /// The operation overrides the content for an existing virtual file with the same `path`.
-    pub fn write_virtual_file(&self, path: impl AsRef<SystemVirtualPath>, content: impl ToString) {
+    pub fn write_virtual_file(
+        &self,
+        path: impl AsRef<SystemVirtualPath>,
+        content: impl Into<Vec<u8>>,
+    ) {
         let path = path.as_ref();
         let mut virtual_files = self.inner.virtual_files.write().unwrap();
 
         match virtual_files.entry(path.to_path_buf()) {
             std::collections::hash_map::Entry::Vacant(entry) => {
                 entry.insert(File {
-                    content: content.to_string(),
+                    content: content.into(),
                     last_modified: file_time_now(),
                 });
             }
             std::collections::hash_map::Entry::Occupied(mut entry) => {
-                entry.get_mut().content = content.to_string();
+                entry.get_mut().content = content.into();
             }
         }
     }
@@ -468,7 +489,7 @@ impl Entry {
 
 #[derive(Debug)]
 struct File {
-    content: String,
+    content: Vec<u8>,
     last_modified: FileTime,
 }
 
@@ -533,7 +554,7 @@ fn get_or_create_file<'a>(
 
     let entry = paths.entry(normalized.to_path_buf()).or_insert_with(|| {
         Entry::File(File {
-            content: String::new(),
+            content: Vec::new(),
             last_modified: file_time_now(),
         })
     });

crates/ruff_db/src/system/os.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::disallowed_methods)]
+
 use super::walk_directory::{
     self, DirectoryWalker, WalkDirectoryBuilder, WalkDirectoryConfiguration,
     WalkDirectoryVisitorBuilder, WalkState,
@@ -91,6 +93,10 @@ impl System for OsSystem {
         })
     }
 
+    fn read_to_end(&self, path: &SystemPath) -> Result<Vec<u8>> {
+        std::fs::read(path.as_std_path())
+    }
+
     fn read_to_string(&self, path: &SystemPath) -> Result<String> {
         std::fs::read_to_string(path.as_std_path())
     }
@@ -255,6 +261,10 @@ impl System for OsSystem {
     fn env_var(&self, name: &str) -> std::result::Result<String, std::env::VarError> {
         std::env::var(name)
     }
+
+    fn dyn_clone(&self) -> Box<dyn System> {
+        Box::new(self.clone())
+    }
 }
 
 impl OsSystem {
@@ -351,7 +361,7 @@ impl WritableSystem for OsSystem {
         std::fs::File::create_new(path).map(drop)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+    fn write_file(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
         std::fs::write(path.as_std_path(), content)
     }
 

crates/ruff_db/src/system/path.rs

@@ -762,7 +762,17 @@ impl SystemVirtualPath {
 }
 
 /// An owned, virtual path on [`System`](`super::System`) (akin to [`String`]).
-#[derive(Eq, PartialEq, Clone, Hash, PartialOrd, Ord, get_size2::GetSize)]
+#[derive(
+    Eq,
+    PartialEq,
+    Clone,
+    Hash,
+    PartialOrd,
+    Ord,
+    get_size2::GetSize,
+    serde::Serialize,
+    serde::Deserialize,
+)]
 pub struct SystemVirtualPathBuf(String);
 
 impl SystemVirtualPathBuf {

crates/ruff_db/src/system/test.rs

@@ -75,6 +75,10 @@ impl System for TestSystem {
         self.system().canonicalize_path(path)
     }
 
+    fn read_to_end(&self, path: &SystemPath) -> Result<Vec<u8>> {
+        self.system().read_to_end(path)
+    }
+
     fn read_to_string(&self, path: &SystemPath) -> Result<String> {
         self.system().read_to_string(path)
     }
@@ -146,6 +150,10 @@ impl System for TestSystem {
     fn case_sensitivity(&self) -> CaseSensitivity {
         self.system().case_sensitivity()
     }
+
+    fn dyn_clone(&self) -> Box<dyn System> {
+        Box::new(self.clone())
+    }
 }
 
 impl Default for TestSystem {
@@ -161,7 +169,7 @@ impl WritableSystem for TestSystem {
         self.system().create_new_file(path)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+    fn write_file(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
         self.system().write_file(path, content)
     }
 
@@ -181,7 +189,9 @@ pub trait DbWithWritableSystem: Db + Sized {
     /// Writes the content of the given file and notifies the Db about the change.
     fn write_file(&mut self, path: impl AsRef<SystemPath>, content: impl AsRef<str>) -> Result<()> {
         let path = path.as_ref();
-        match self.writable_system().write_file(path, content.as_ref()) {
+        let content = content.as_ref();
+
+        match self.writable_system().write_file(path, content.as_bytes()) {
             Ok(()) => {
                 File::sync_path(self, path);
                 Ok(())
@@ -194,7 +204,8 @@ pub trait DbWithWritableSystem: Db + Sized {
                         File::sync_path(self, ancestor);
                     }
 
-                    self.writable_system().write_file(path, content.as_ref())?;
+                    self.writable_system()
+                        .write_file(path, content.as_bytes())?;
                     File::sync_path(self, path);
 
                     Ok(())
@@ -239,8 +250,14 @@ pub trait DbWithTestSystem: Db + Sized {
     ///
     /// ## Panics
     /// If the db isn't using the [`InMemorySystem`].
-    fn write_virtual_file(&mut self, path: impl AsRef<SystemVirtualPath>, content: impl ToString) {
+    fn write_virtual_file(
+        &mut self,
+        path: impl AsRef<SystemVirtualPath>,
+        content: impl Into<Vec<u8>>,
+    ) {
         let path = path.as_ref();
+        let content = content.into();
+
         self.test_system()
             .memory_file_system()
             .write_virtual_file(path, content);
@@ -318,6 +335,10 @@ impl System for InMemorySystem {
         self.memory_fs.canonicalize(path)
     }
 
+    fn read_to_end(&self, path: &SystemPath) -> Result<Vec<u8>> {
+        self.memory_fs.read_to_end(path)
+    }
+
     fn read_to_string(&self, path: &SystemPath) -> Result<String> {
         self.memory_fs.read_to_string(path)
     }
@@ -394,6 +415,13 @@ impl System for InMemorySystem {
     fn case_sensitivity(&self) -> CaseSensitivity {
         CaseSensitivity::CaseSensitive
     }
+
+    fn dyn_clone(&self) -> Box<dyn System> {
+        Box::new(Self {
+            user_config_directory: Mutex::new(self.user_config_directory.lock().unwrap().clone()),
+            memory_fs: self.memory_fs.clone(),
+        })
+    }
 }
 
 impl WritableSystem for InMemorySystem {
@@ -401,7 +429,7 @@ impl WritableSystem for InMemorySystem {
         self.memory_fs.create_new_file(path)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+    fn write_file(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
         self.memory_fs.write_file(path, content)
     }
 

crates/ruff_db/src/vendored/path.rs

@@ -88,7 +88,7 @@ impl ToOwned for VendoredPath {
 }
 
 #[repr(transparent)]
-#[derive(Debug, Eq, PartialEq, Clone, Hash)]
+#[derive(Debug, Eq, PartialEq, Clone, Hash, serde::Serialize, serde::Deserialize)]
 pub struct VendoredPathBuf(Utf8PathBuf);
 
 impl get_size2::GetSize for VendoredPathBuf {

crates/ruff_linter/resources/test/fixtures/flake8_use_pathlib/PTH211.py

@@ -13,3 +13,11 @@ Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
 fd = os.open(".", os.O_RDONLY)
 os.symlink("source.txt", "link.txt", dir_fd=fd)  # Ok: dir_fd is not supported by pathlib
 os.close(fd)
+
+os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+
+os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+
+os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")

crates/ruff_linter/resources/test/fixtures/ruff/RUF026.py

@@ -118,3 +118,10 @@ def func():
         return lambda: value
 
     defaultdict(constant_factory("<missing>"))
+
+def func():
+    defaultdict(default_factory=t"")  # OK
+
+
+def func():
+    defaultdict(default_factory=t"hello")  # OK

crates/ruff_linter/resources/test/fixtures/ruff/RUF037.py

@@ -102,3 +102,8 @@ deque("abc") # OK
 deque(b"abc") # OK
 deque(f"" "a")  # OK
 deque(f"{x}" "")  # OK
+
+# https://github.com/astral-sh/ruff/issues/19951
+deque(t"")
+deque(t""  t"")
+deque(t"{""}") # OK

crates/ruff_linter/src/checkers/ast/analyze/expression.rs

@@ -1124,6 +1124,9 @@ pub(crate) fn expression(expr: &Expr, checker: &Checker) {
                 if checker.is_rule_enabled(Rule::OsMakedirs) {
                     flake8_use_pathlib::rules::os_makedirs(checker, call, segments);
                 }
+                if checker.is_rule_enabled(Rule::OsSymlink) {
+                    flake8_use_pathlib::rules::os_symlink(checker, call, segments);
+                }
                 if checker.is_rule_enabled(Rule::PathConstructorCurrentDirectory) {
                     flake8_use_pathlib::rules::path_constructor_current_directory(
                         checker, call, segments,

crates/ruff_linter/src/codes.rs

@@ -954,7 +954,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Flake8UsePathlib, "207") => (RuleGroup::Stable, rules::flake8_use_pathlib::rules::Glob),
         (Flake8UsePathlib, "208") => (RuleGroup::Stable, rules::flake8_use_pathlib::violations::OsListdir),
         (Flake8UsePathlib, "210") => (RuleGroup::Stable, rules::flake8_use_pathlib::rules::InvalidPathlibWithSuffix),
-        (Flake8UsePathlib, "211") => (RuleGroup::Preview, rules::flake8_use_pathlib::violations::OsSymlink),
+        (Flake8UsePathlib, "211") => (RuleGroup::Preview, rules::flake8_use_pathlib::rules::OsSymlink),
 
         // flake8-logging-format
         (Flake8LoggingFormat, "001") => (RuleGroup::Stable, rules::flake8_logging_format::violations::LoggingStringFormat),

crates/ruff_linter/src/preview.rs

@@ -169,6 +169,11 @@ pub(crate) const fn is_fix_os_makedirs_enabled(settings: &LinterSettings) -> boo
     settings.preview.is_enabled()
 }
 
+// https://github.com/astral-sh/ruff/pull/20009
+pub(crate) const fn is_fix_os_symlink_enabled(settings: &LinterSettings) -> bool {
+    settings.preview.is_enabled()
+}
+
 // https://github.com/astral-sh/ruff/pull/11436
 // https://github.com/astral-sh/ruff/pull/11168
 pub(crate) const fn is_dunder_init_fix_unused_import_enabled(settings: &LinterSettings) -> bool {

crates/ruff_linter/src/rules/flake8_annotations/helpers.rs

@@ -137,7 +137,7 @@ impl AutoPythonType {
                 let expr = Expr::Name(ast::ExprName {
                     id: Name::from(binding),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     ctx: ExprContext::Load,
                 });
                 Some((expr, vec![no_return_edit]))
@@ -204,7 +204,7 @@ fn type_expr(python_type: PythonType) -> Option<Expr> {
         Expr::Name(ast::ExprName {
             id: name.into(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         })
     }

crates/ruff_linter/src/rules/flake8_bugbear/rules/assert_false.rs

@@ -52,13 +52,13 @@ impl AlwaysFixableViolation for AssertFalse {
 fn assertion_error(msg: Option<&Expr>) -> Stmt {
     Stmt::Raise(ast::StmtRaise {
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         exc: Some(Box::new(Expr::Call(ast::ExprCall {
             func: Box::new(Expr::Name(ast::ExprName {
                 id: "AssertionError".into(),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             })),
             arguments: Arguments {
                 args: if let Some(msg) = msg {
@@ -68,10 +68,10 @@ fn assertion_error(msg: Option<&Expr>) -> Stmt {
                 },
                 keywords: Box::from([]),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             },
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         }))),
         cause: None,
     })

crates/ruff_linter/src/rules/flake8_bugbear/rules/duplicate_exceptions.rs

@@ -113,7 +113,7 @@ fn type_pattern(elts: Vec<&Expr>) -> Expr {
         elts: elts.into_iter().cloned().collect(),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         parenthesized: true,
     }
     .into()

crates/ruff_linter/src/rules/flake8_bugbear/rules/setattr_with_constant.rs

@@ -53,11 +53,11 @@ fn assignment(obj: &Expr, name: &str, value: &Expr, generator: Generator) -> Str
             attr: Identifier::new(name.to_string(), TextRange::default()),
             ctx: ExprContext::Store,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })],
         value: Box::new(value.clone()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     });
     generator.stmt(&stmt)
 }

crates/ruff_linter/src/rules/flake8_commas/mod.rs

@@ -10,7 +10,7 @@ mod tests {
 
     use crate::registry::Rule;
     use crate::test::test_path;
-    use crate::{assert_diagnostics, settings};
+    use crate::{assert_diagnostics, assert_diagnostics_diff, settings};
 
     #[test_case(Path::new("COM81.py"))]
     #[test_case(Path::new("COM81_syntax_error.py"))]
@@ -31,19 +31,24 @@ mod tests {
     #[test_case(Path::new("COM81.py"))]
     #[test_case(Path::new("COM81_syntax_error.py"))]
     fn preview_rules(path: &Path) -> Result<()> {
-        let snapshot = format!("preview__{}", path.to_string_lossy());
-        let diagnostics = test_path(
+        let snapshot = format!("preview_diff__{}", path.to_string_lossy());
+        let rules = vec![
+            Rule::MissingTrailingComma,
+            Rule::TrailingCommaOnBareTuple,
+            Rule::ProhibitedTrailingComma,
+        ];
+        let settings_before = settings::LinterSettings::for_rules(rules.clone());
+        let settings_after = settings::LinterSettings {
+            preview: crate::settings::types::PreviewMode::Enabled,
+            ..settings::LinterSettings::for_rules(rules)
+        };
+
+        assert_diagnostics_diff!(
+            snapshot,
             Path::new("flake8_commas").join(path).as_path(),
-            &settings::LinterSettings {
-                preview: crate::settings::types::PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rules(vec![
-                    Rule::MissingTrailingComma,
-                    Rule::TrailingCommaOnBareTuple,
-                    Rule::ProhibitedTrailingComma,
-                ])
-            },
-        )?;
-        assert_diagnostics!(snapshot, diagnostics);
+            &settings_before,
+            &settings_after
+        );
         Ok(())
     }
 }

crates/ruff_linter/src/rules/flake8_commas/snapshots/ruff_linter__rules__flake8_commas__tests__preview__COM81_syntax_error.py.snap

@@ -1,33 +0,0 @@
----
-source: crates/ruff_linter/src/rules/flake8_commas/mod.rs
----
-invalid-syntax: Starred expression cannot be used here
- --> COM81_syntax_error.py:3:5
-  |
-1 | # Check for `flake8-commas` violation for a file containing syntax errors.
-2 | (
-3 |     *args
-  |     ^^^^^
-4 | )
-  |
-
-invalid-syntax: Type parameter list cannot be empty
- --> COM81_syntax_error.py:6:9
-  |
-4 | )
-5 |
-6 | def foo[(param1='test', param2='test',):
-  |         ^
-7 |     pass
-  |
-
-COM819 Trailing comma prohibited
- --> COM81_syntax_error.py:6:38
-  |
-4 | )
-5 |
-6 | def foo[(param1='test', param2='test',):
-  |                                      ^
-7 |     pass
-  |
-help: Remove trailing comma

crates/ruff_linter/src/rules/flake8_commas/snapshots/ruff_linter__rules__flake8_commas__tests__preview_diff__COM81.py.snap

@@ -0,0 +1,136 @@
+---
+source: crates/ruff_linter/src/rules/flake8_commas/mod.rs
+---
+--- Linter settings ---
+-linter.preview = disabled
++linter.preview = enabled
+
+--- Summary ---
+Removed: 0
+Added: 6
+
+--- Added ---
+COM812 [*] Trailing comma missing
+   --> COM81.py:655:6
+    |
+654 | type X[
+655 |     T
+    |      ^
+656 | ] = T
+657 | def f[
+    |
+help: Add trailing comma
+
+ℹ Safe fix
+652 652 | }"""
+653 653 | 
+654 654 | type X[
+655     |-    T
+    655 |+    T,
+656 656 | ] = T
+657 657 | def f[
+658 658 |     T
+
+
+COM812 [*] Trailing comma missing
+   --> COM81.py:658:6
+    |
+656 | ] = T
+657 | def f[
+658 |     T
+    |      ^
+659 | ](): pass
+660 | class C[
+    |
+help: Add trailing comma
+
+ℹ Safe fix
+655 655 |     T
+656 656 | ] = T
+657 657 | def f[
+658     |-    T
+    658 |+    T,
+659 659 | ](): pass
+660 660 | class C[
+661 661 |     T
+
+
+COM812 [*] Trailing comma missing
+   --> COM81.py:661:6
+    |
+659 | ](): pass
+660 | class C[
+661 |     T
+    |      ^
+662 | ]: pass
+    |
+help: Add trailing comma
+
+ℹ Safe fix
+658 658 |     T
+659 659 | ](): pass
+660 660 | class C[
+661     |-    T
+    661 |+    T,
+662 662 | ]: pass
+663 663 | 
+664 664 | type X[T,] = T
+
+
+COM819 [*] Trailing comma prohibited
+   --> COM81.py:664:9
+    |
+662 | ]: pass
+663 |
+664 | type X[T,] = T
+    |         ^
+665 | def f[T,](): pass
+666 | class C[T,]: pass
+    |
+help: Remove trailing comma
+
+ℹ Safe fix
+661 661 |     T
+662 662 | ]: pass
+663 663 | 
+664     |-type X[T,] = T
+    664 |+type X[T] = T
+665 665 | def f[T,](): pass
+666 666 | class C[T,]: pass
+
+
+COM819 [*] Trailing comma prohibited
+   --> COM81.py:665:8
+    |
+664 | type X[T,] = T
+665 | def f[T,](): pass
+    |        ^
+666 | class C[T,]: pass
+    |
+help: Remove trailing comma
+
+ℹ Safe fix
+662 662 | ]: pass
+663 663 | 
+664 664 | type X[T,] = T
+665     |-def f[T,](): pass
+    665 |+def f[T](): pass
+666 666 | class C[T,]: pass
+
+
+COM819 [*] Trailing comma prohibited
+   --> COM81.py:666:10
+    |
+664 | type X[T,] = T
+665 | def f[T,](): pass
+666 | class C[T,]: pass
+    |          ^
+    |
+help: Remove trailing comma
+
+ℹ Safe fix
+663 663 | 
+664 664 | type X[T,] = T
+665 665 | def f[T,](): pass
+666     |-class C[T,]: pass
+    666 |+class C[T]: pass

crates/ruff_linter/src/rules/flake8_commas/snapshots/ruff_linter__rules__flake8_commas__tests__preview_diff__COM81_syntax_error.py.snap

@@ -0,0 +1,10 @@
+---
+source: crates/ruff_linter/src/rules/flake8_commas/mod.rs
+---
+--- Linter settings ---
+-linter.preview = disabled
++linter.preview = enabled
+
+--- Summary ---
+Removed: 0
+Added: 0

crates/ruff_linter/src/rules/flake8_comprehensions/rules/unnecessary_dict_comprehension_for_iterable.rs

@@ -209,18 +209,18 @@ fn fix_unnecessary_dict_comprehension(value: &Expr, generator: &Comprehension) -
         },
         keywords: Box::from([]),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     Expr::Call(ExprCall {
         func: Box::new(Expr::Name(ExprName {
             id: "dict.fromkeys".into(),
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })),
         arguments: args,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 

crates/ruff_linter/src/rules/flake8_pie/rules/multiple_starts_ends_with.rs

@@ -178,21 +178,21 @@ pub(crate) fn multiple_starts_ends_with(checker: &Checker, expr: &Expr) {
                     .collect(),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 parenthesized: true,
             });
             let node1 = Expr::Name(ast::ExprName {
                 id: arg_name.into(),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let node2 = Expr::Attribute(ast::ExprAttribute {
                 value: Box::new(node1),
                 attr: Identifier::new(attr_name.to_string(), TextRange::default()),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let node3 = Expr::Call(ast::ExprCall {
                 func: Box::new(node2),
@@ -200,10 +200,10 @@ pub(crate) fn multiple_starts_ends_with(checker: &Checker, expr: &Expr) {
                     args: Box::from([node]),
                     keywords: Box::from([]),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 },
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let call = node3;
 
@@ -223,7 +223,7 @@ pub(crate) fn multiple_starts_ends_with(checker: &Checker, expr: &Expr) {
                     })
                     .collect(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let bool_op = node;
             diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(

crates/ruff_linter/src/rules/flake8_pyi/rules/duplicate_literal_member.rs

@@ -92,14 +92,14 @@ pub(crate) fn duplicate_literal_member<'a>(checker: &Checker, expr: &'a Expr) {
                 Expr::Tuple(ast::ExprTuple {
                     elts: unique_nodes.into_iter().cloned().collect(),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     ctx: ExprContext::Load,
                     parenthesized: false,
                 })
             }),
             value: subscript.value.clone(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         });
         let fix = Fix::applicable_edit(

crates/ruff_linter/src/rules/flake8_pyi/rules/duplicate_union_member.rs

@@ -187,7 +187,7 @@ fn generate_pep604_fix(
                     op: Operator::BitOr,
                     right: Box::new(right.clone()),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 }))
             } else {
                 Some(right.clone())
@@ -202,7 +202,7 @@ fn generate_pep604_fix(
 }
 
 static VIRTUAL_NONE_LITERAL: Expr = Expr::NoneLiteral(ExprNoneLiteral {
-    node_index: AtomicNodeIndex::dummy(),
+    node_index: AtomicNodeIndex::NONE,
     range: TextRange::new(TextSize::new(0), TextSize::new(0)),
 });
 

crates/ruff_linter/src/rules/flake8_pyi/rules/mod.rs

@@ -133,17 +133,17 @@ fn generate_union_fix(
     // Construct the expression as `Subscript[typing.Union, Tuple[expr, [expr, ...]]]`
     let new_expr = Expr::Subscript(ExprSubscript {
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         value: Box::new(Expr::Name(ExprName {
             id: Name::new(binding),
             ctx: ExprContext::Store,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })),
         slice: Box::new(Expr::Tuple(ExprTuple {
             elts: nodes.into_iter().cloned().collect(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
             parenthesized: false,
         })),

crates/ruff_linter/src/rules/flake8_pyi/rules/redundant_none_literal.rs

@@ -205,13 +205,13 @@ fn create_fix(
     let new_literal_expr = Expr::Subscript(ast::ExprSubscript {
         value: Box::new(literal_subscript.clone()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         ctx: ExprContext::Load,
         slice: Box::new(if literal_elements.len() > 1 {
             Expr::Tuple(ast::ExprTuple {
                 elts: literal_elements.into_iter().cloned().collect(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 ctx: ExprContext::Load,
                 parenthesized: true,
             })
@@ -235,7 +235,7 @@ fn create_fix(
         UnionKind::BitOr => {
             let none_expr = Expr::NoneLiteral(ExprNoneLiteral {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let union_expr = pep_604_union(&[new_literal_expr, none_expr]);
             let content = checker.generator().expr(&union_expr);

crates/ruff_linter/src/rules/flake8_pyi/rules/redundant_numeric_union.rs

@@ -261,7 +261,7 @@ fn generate_pep604_fix(
                     op: Operator::BitOr,
                     right: Box::new(right.clone()),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 }))
             } else {
                 Some(right.clone())

crates/ruff_linter/src/rules/flake8_pyi/rules/unnecessary_literal_union.rs

@@ -140,12 +140,12 @@ pub(crate) fn unnecessary_literal_union<'a>(checker: &Checker, expr: &'a Expr) {
             slice: Box::new(Expr::Tuple(ast::ExprTuple {
                 elts: literal_exprs.into_iter().cloned().collect(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 ctx: ExprContext::Load,
                 parenthesized: true,
             })),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         });
 
@@ -164,12 +164,12 @@ pub(crate) fn unnecessary_literal_union<'a>(checker: &Checker, expr: &'a Expr) {
                         slice: Box::new(Expr::Tuple(ast::ExprTuple {
                             elts,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             ctx: ExprContext::Load,
                             parenthesized: true,
                         })),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         ctx: ExprContext::Load,
                     }))
             } else {

crates/ruff_linter/src/rules/flake8_pyi/rules/unnecessary_type_union.rs

@@ -134,12 +134,12 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &Checker, union: &'a Expr) {
                         id: Name::new_static("type"),
                         ctx: ExprContext::Load,
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     })),
                     slice: Box::new(pep_604_union(&elts)),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 });
 
                 if other_exprs.is_empty() {
@@ -159,7 +159,7 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &Checker, union: &'a Expr) {
                         id: Name::new_static("type"),
                         ctx: ExprContext::Load,
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     })),
                     slice: Box::new(Expr::Subscript(ast::ExprSubscript {
                         value: subscript.value.clone(),
@@ -171,22 +171,22 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &Checker, union: &'a Expr) {
                                         id: type_member,
                                         ctx: ExprContext::Load,
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                     })
                                 })
                                 .collect(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             parenthesized: true,
                         })),
                         ctx: ExprContext::Load,
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     })),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 });
 
                 if other_exprs.is_empty() {
@@ -202,12 +202,12 @@ pub(crate) fn unnecessary_type_union<'a>(checker: &Checker, union: &'a Expr) {
                             elts: exprs.into_iter().cloned().collect(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             parenthesized: true,
                         })),
                         ctx: ExprContext::Load,
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     });
 
                     checker.generator().expr(&union)

crates/ruff_linter/src/rules/flake8_pytest_style/rules/parametrize.rs

@@ -301,7 +301,7 @@ fn elts_to_csv(elts: &[Expr], generator: Generator, flags: StringLiteralFlags) -
             })
             .into_boxed_str(),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         flags,
     });
     Some(generator.expr(&node))
@@ -367,14 +367,14 @@ fn check_names(checker: &Checker, call: &ExprCall, expr: &Expr, argvalues: &Expr
                                     Expr::from(ast::StringLiteral {
                                         value: Box::from(*name),
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                         flags: checker.default_string_flags(),
                                     })
                                 })
                                 .collect(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             parenthesized: true,
                         });
                         diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
@@ -404,14 +404,14 @@ fn check_names(checker: &Checker, call: &ExprCall, expr: &Expr, argvalues: &Expr
                                     Expr::from(ast::StringLiteral {
                                         value: Box::from(*name),
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                         flags: checker.default_string_flags(),
                                     })
                                 })
                                 .collect(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         });
                         diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
                             checker.generator().expr(&node),
@@ -440,7 +440,7 @@ fn check_names(checker: &Checker, call: &ExprCall, expr: &Expr, argvalues: &Expr
                             elts: elts.clone(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         });
                         diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
                             checker.generator().expr(&node),
@@ -485,7 +485,7 @@ fn check_names(checker: &Checker, call: &ExprCall, expr: &Expr, argvalues: &Expr
                             elts: elts.clone(),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             parenthesized: true,
                         });
                         diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(

crates/ruff_linter/src/rules/flake8_pytest_style/rules/unittest_assert.rs

@@ -166,7 +166,7 @@ fn assert(expr: &Expr, msg: Option<&Expr>) -> Stmt {
         test: Box::new(expr.clone()),
         msg: msg.map(|msg| Box::new(msg.clone())),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 
@@ -176,7 +176,7 @@ fn compare(left: &Expr, cmp_op: CmpOp, right: &Expr) -> Expr {
         ops: Box::from([cmp_op]),
         comparators: Box::from([right.clone()]),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 
@@ -296,7 +296,7 @@ impl UnittestAssert {
                                 op: UnaryOp::Not,
                                 operand: Box::new(expr.clone()),
                                 range: TextRange::default(),
-                                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             }),
                             msg,
                         )
@@ -370,7 +370,7 @@ impl UnittestAssert {
                 };
                 let node = Expr::NoneLiteral(ast::ExprNoneLiteral {
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 });
                 let expr = compare(expr, cmp_op, &node);
                 Ok(assert(&expr, msg))
@@ -387,7 +387,7 @@ impl UnittestAssert {
                     id: Name::new_static("isinstance"),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 };
                 let node1 = ast::ExprCall {
                     func: Box::new(node.into()),
@@ -395,10 +395,10 @@ impl UnittestAssert {
                         args: Box::from([(**obj).clone(), (**cls).clone()]),
                         keywords: Box::from([]),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     },
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 };
                 let isinstance = node1.into();
                 if matches!(self, UnittestAssert::IsInstance) {
@@ -408,7 +408,7 @@ impl UnittestAssert {
                         op: UnaryOp::Not,
                         operand: Box::new(isinstance),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     };
                     let expr = node.into();
                     Ok(assert(&expr, msg))
@@ -429,14 +429,14 @@ impl UnittestAssert {
                     id: Name::new_static("re"),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 };
                 let node1 = ast::ExprAttribute {
                     value: Box::new(node.into()),
                     attr: Identifier::new("search".to_string(), TextRange::default()),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 };
                 let node2 = ast::ExprCall {
                     func: Box::new(node1.into()),
@@ -444,10 +444,10 @@ impl UnittestAssert {
                         args: Box::from([(**regex).clone(), (**text).clone()]),
                         keywords: Box::from([]),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     },
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 };
                 let re_search = node2.into();
                 if matches!(self, UnittestAssert::Regex | UnittestAssert::RegexpMatches) {
@@ -457,7 +457,7 @@ impl UnittestAssert {
                         op: UnaryOp::Not,
                         operand: Box::new(re_search),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     };
                     Ok(assert(&node.into(), msg))
                 }

crates/ruff_linter/src/rules/flake8_simplify/rules/ast_bool_op.rs

@@ -421,7 +421,7 @@ pub(crate) fn duplicate_isinstance_call(checker: &Checker, expr: &Expr) {
                         .collect(),
                     ctx: ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     parenthesized: true,
                 };
                 let isinstance_call = ast::ExprCall {
@@ -430,7 +430,7 @@ pub(crate) fn duplicate_isinstance_call(checker: &Checker, expr: &Expr) {
                             id: Name::new_static("isinstance"),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         }
                         .into(),
                     ),
@@ -438,10 +438,10 @@ pub(crate) fn duplicate_isinstance_call(checker: &Checker, expr: &Expr) {
                         args: Box::from([target.clone(), tuple.into()]),
                         keywords: Box::from([]),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     },
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 }
                 .into();
 
@@ -458,7 +458,7 @@ pub(crate) fn duplicate_isinstance_call(checker: &Checker, expr: &Expr) {
                         .chain(after)
                         .collect(),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 }
                 .into();
                 let fixed_source = checker.generator().expr(&bool_op);
@@ -552,21 +552,21 @@ pub(crate) fn compare_with_tuple(checker: &Checker, expr: &Expr) {
             elts: comparators.into_iter().cloned().collect(),
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             parenthesized: true,
         };
         let node1 = ast::ExprName {
             id: id.clone(),
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         let node2 = ast::ExprCompare {
             left: Box::new(node1.into()),
             ops: Box::from([CmpOp::In]),
             comparators: Box::from([node.into()]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         let in_expr = node2.into();
         let mut diagnostic = checker.report_diagnostic(
@@ -589,7 +589,7 @@ pub(crate) fn compare_with_tuple(checker: &Checker, expr: &Expr) {
                 op: BoolOp::Or,
                 values: iter::once(in_expr).chain(unmatched).collect(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             };
             node.into()
         };

crates/ruff_linter/src/rules/flake8_simplify/rules/ast_expr.rs

@@ -232,7 +232,7 @@ fn check_os_environ_subscript(checker: &Checker, expr: &Expr) {
             }
         }),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let new_env_var = node.into();
     diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(

crates/ruff_linter/src/rules/flake8_simplify/rules/ast_ifexp.rs

@@ -188,7 +188,7 @@ pub(crate) fn if_expr_with_true_false(
                             id: Name::new_static("bool"),
                             ctx: ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         }
                         .into(),
                     ),
@@ -196,10 +196,10 @@ pub(crate) fn if_expr_with_true_false(
                         args: Box::from([test.clone()]),
                         keywords: Box::from([]),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     },
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 }
                 .into(),
             ),
@@ -227,7 +227,7 @@ pub(crate) fn if_expr_with_false_true(
                 op: UnaryOp::Not,
                 operand: Box::new(test.clone()),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
         ),
@@ -282,7 +282,7 @@ pub(crate) fn twisted_arms_in_ifexpr(
         body: Box::new(node1),
         orelse: Box::new(node),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
         checker.generator().expr(&node3.into()),

crates/ruff_linter/src/rules/flake8_simplify/rules/ast_unary_op.rs

@@ -186,7 +186,7 @@ pub(crate) fn negation_with_equal_op(checker: &Checker, expr: &Expr, op: UnaryOp
         ops: Box::from([CmpOp::NotEq]),
         comparators: comparators.clone(),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
         checker.generator().expr(&node.into()),
@@ -242,7 +242,7 @@ pub(crate) fn negation_with_not_equal_op(
         ops: Box::from([CmpOp::Eq]),
         comparators: comparators.clone(),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
         checker.generator().expr(&node.into()),
@@ -284,7 +284,7 @@ pub(crate) fn double_negation(checker: &Checker, expr: &Expr, op: UnaryOp, opera
             id: Name::new_static("bool"),
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         let node1 = ast::ExprCall {
             func: Box::new(node.into()),
@@ -292,10 +292,10 @@ pub(crate) fn double_negation(checker: &Checker, expr: &Expr, op: UnaryOp, opera
                 args: Box::from([*operand.clone()]),
                 keywords: Box::from([]),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             },
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(
             checker.generator().expr(&node1.into()),

crates/ruff_linter/src/rules/flake8_simplify/rules/if_else_block_instead_of_dict_get.rs

@@ -190,7 +190,7 @@ pub(crate) fn if_else_block_instead_of_dict_get(checker: &Checker, stmt_if: &ast
         attr: Identifier::new("get".to_string(), TextRange::default()),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node3 = ast::ExprCall {
         func: Box::new(node2.into()),
@@ -198,17 +198,17 @@ pub(crate) fn if_else_block_instead_of_dict_get(checker: &Checker, stmt_if: &ast
             args: Box::from([node1, node]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node4 = expected_var.clone();
     let node5 = ast::StmtAssign {
         targets: vec![node4],
         value: Box::new(node3.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let contents = checker.generator().stmt(&node5.into());
 
@@ -299,7 +299,7 @@ pub(crate) fn if_exp_instead_of_dict_get(
         attr: Identifier::new("get".to_string(), TextRange::default()),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let fixed_node = ast::ExprCall {
         func: Box::new(dict_get_node.into()),
@@ -307,10 +307,10 @@ pub(crate) fn if_exp_instead_of_dict_get(
             args: Box::from([dict_key_node, default_value_node]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
 
     let contents = checker.generator().expr(&fixed_node.into());

crates/ruff_linter/src/rules/flake8_simplify/rules/if_else_block_instead_of_if_exp.rs

@@ -266,13 +266,13 @@ fn assignment_ternary(
         body: Box::new(body_value.clone()),
         orelse: Box::new(orelse_value.clone()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node1 = ast::StmtAssign {
         targets: vec![target_var.clone()],
         value: Box::new(node.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     node1.into()
 }
@@ -282,13 +282,13 @@ fn assignment_binary_and(target_var: &Expr, left_value: &Expr, right_value: &Exp
         op: BoolOp::And,
         values: vec![left_value.clone(), right_value.clone()],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node1 = ast::StmtAssign {
         targets: vec![target_var.clone()],
         value: Box::new(node.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     node1.into()
 }
@@ -296,12 +296,12 @@ fn assignment_binary_and(target_var: &Expr, left_value: &Expr, right_value: &Exp
 fn assignment_binary_or(target_var: &Expr, left_value: &Expr, right_value: &Expr) -> Stmt {
     (ast::StmtAssign {
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         targets: vec![target_var.clone()],
         value: Box::new(
             (ast::ExprBoolOp {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 op: BoolOp::Or,
                 values: vec![left_value.clone(), right_value.clone()],
             })

crates/ruff_linter/src/rules/flake8_simplify/rules/needless_bool.rs

@@ -256,7 +256,7 @@ pub(crate) fn needless_bool(checker: &Checker, stmt: &Stmt) {
                         left: left.clone(),
                         comparators: Box::new([right.clone()]),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     }))
                 }
 
@@ -264,7 +264,7 @@ pub(crate) fn needless_bool(checker: &Checker, stmt: &Stmt) {
                     op: ast::UnaryOp::Not,
                     operand: Box::new(if_test.clone()),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 })),
             }
         } else if if_test.is_compare_expr() {
@@ -277,7 +277,7 @@ pub(crate) fn needless_bool(checker: &Checker, stmt: &Stmt) {
                 id: Name::new_static("bool"),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             };
             let call_node = ast::ExprCall {
                 func: Box::new(func_node.into()),
@@ -285,10 +285,10 @@ pub(crate) fn needless_bool(checker: &Checker, stmt: &Stmt) {
                     args: Box::from([if_test.clone()]),
                     keywords: Box::from([]),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 },
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             };
             Some(Expr::Call(call_node))
         } else {
@@ -301,7 +301,7 @@ pub(crate) fn needless_bool(checker: &Checker, stmt: &Stmt) {
         Stmt::Return(ast::StmtReturn {
             value: Some(Box::new(expr.clone())),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })
     });
 

crates/ruff_linter/src/rules/flake8_simplify/rules/reimplemented_builtin.rs

@@ -165,7 +165,7 @@ pub(crate) fn convert_for_loop_to_any_all(checker: &Checker, stmt: &Stmt) {
                             ops: Box::from([op]),
                             comparators: Box::from([comparator.clone()]),
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         };
                         node.into()
                     } else {
@@ -173,7 +173,7 @@ pub(crate) fn convert_for_loop_to_any_all(checker: &Checker, stmt: &Stmt) {
                             op: UnaryOp::Not,
                             operand: Box::new(loop_.test.clone()),
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         };
                         node.into()
                     }
@@ -182,7 +182,7 @@ pub(crate) fn convert_for_loop_to_any_all(checker: &Checker, stmt: &Stmt) {
                         op: UnaryOp::Not,
                         operand: Box::new(loop_.test.clone()),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     };
                     node.into()
                 }
@@ -406,17 +406,17 @@ fn return_stmt(id: Name, test: &Expr, target: &Expr, iter: &Expr, generator: Gen
             ifs: vec![],
             is_async: false,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         }],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         parenthesized: false,
     };
     let node1 = ast::ExprName {
         id,
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node2 = ast::ExprCall {
         func: Box::new(node1.into()),
@@ -424,15 +424,15 @@ fn return_stmt(id: Name, test: &Expr, target: &Expr, iter: &Expr, generator: Gen
             args: Box::from([node.into()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let node3 = ast::StmtReturn {
         value: Some(Box::new(node2.into())),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.stmt(&node3.into())
 }

crates/ruff_linter/src/rules/flake8_simplify/rules/split_static_string.rs

@@ -163,14 +163,14 @@ fn construct_replacement(elts: &[&str], flags: StringLiteralFlags) -> Expr {
                 Expr::from(StringLiteral {
                     value: Box::from(*elt),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     flags: element_flags,
                 })
             })
             .collect(),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 

crates/ruff_linter/src/rules/flake8_tidy_imports/rules/relative_imports.rs

@@ -101,7 +101,7 @@ fn fix_banned_relative_import(
         names: names.clone(),
         level: 0,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let content = generator.stmt(&node.into());
     Some(Fix::unsafe_edit(Edit::range_replacement(

crates/ruff_linter/src/rules/flake8_type_checking/helpers.rs

@@ -436,7 +436,7 @@ impl<'a> QuoteAnnotator<'a> {
         let annotation = subgenerator.expr(&expr_without_forward_references);
         generator.expr(&Expr::from(ast::StringLiteral {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             value: annotation.into_boxed_str(),
             flags: self.flags,
         }))

crates/ruff_linter/src/rules/flake8_use_pathlib/mod.rs

@@ -129,6 +129,7 @@ mod tests {
     #[test_case(Rule::OsPathGetatime, Path::new("PTH203.py"))]
     #[test_case(Rule::OsPathGetmtime, Path::new("PTH204.py"))]
     #[test_case(Rule::OsPathGetctime, Path::new("PTH205.py"))]
+    #[test_case(Rule::OsSymlink, Path::new("PTH211.py"))]
     fn preview_flake8_use_pathlib(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!(
             "preview__{}_{}",

crates/ruff_linter/src/rules/flake8_use_pathlib/rules/mod.rs

@@ -24,6 +24,7 @@ pub(crate) use os_rename::*;
 pub(crate) use os_replace::*;
 pub(crate) use os_rmdir::*;
 pub(crate) use os_sep_split::*;
+pub(crate) use os_symlink::*;
 pub(crate) use os_unlink::*;
 pub(crate) use path_constructor_current_directory::*;
 pub(crate) use replaceable_by_pathlib::*;
@@ -54,6 +55,7 @@ mod os_rename;
 mod os_replace;
 mod os_rmdir;
 mod os_sep_split;
+mod os_symlink;
 mod os_unlink;
 mod path_constructor_current_directory;
 mod replaceable_by_pathlib;

crates/ruff_linter/src/rules/flake8_use_pathlib/rules/os_symlink.rs

@@ -0,0 +1,153 @@
+use ruff_diagnostics::{Applicability, Edit, Fix};
+use ruff_macros::{ViolationMetadata, derive_message_formats};
+use ruff_python_ast::ExprCall;
+use ruff_text_size::Ranged;
+
+use crate::checkers::ast::Checker;
+use crate::importer::ImportRequest;
+use crate::preview::is_fix_os_symlink_enabled;
+use crate::rules::flake8_use_pathlib::helpers::{
+    has_unknown_keywords_or_starred_expr, is_keyword_only_argument_non_default,
+    is_pathlib_path_call,
+};
+use crate::{FixAvailability, Violation};
+
+/// ## What it does
+/// Checks for uses of `os.symlink`.
+///
+/// ## Why is this bad?
+/// `pathlib` offers a high-level API for path manipulation, as compared to
+/// the lower-level API offered by `os.symlink`.
+///
+/// ## Example
+/// ```python
+/// import os
+///
+/// os.symlink("usr/bin/python", "tmp/python", target_is_directory=False)
+/// ```
+///
+/// Use instead:
+/// ```python
+/// from pathlib import Path
+///
+/// Path("tmp/python").symlink_to("usr/bin/python")
+/// ```
+///
+/// ## Known issues
+/// While using `pathlib` can improve the readability and type safety of your code,
+/// it can be less performant than the lower-level alternatives that work directly with strings,
+/// especially on older versions of Python.
+///
+/// ## Fix Safety
+/// This rule's fix is marked as unsafe if the replacement would remove comments attached to the original expression.
+///
+/// ## References
+/// - [Python documentation: `Path.symlink_to`](https://docs.python.org/3/library/pathlib.html#pathlib.Path.symlink_to)
+/// - [PEP 428 – The pathlib module – object-oriented filesystem paths](https://peps.python.org/pep-0428/)
+/// - [Correspondence between `os` and `pathlib`](https://docs.python.org/3/library/pathlib.html#correspondence-to-tools-in-the-os-module)
+/// - [Why you should be using pathlib](https://treyhunner.com/2018/12/why-you-should-be-using-pathlib/)
+/// - [No really, pathlib is great](https://treyhunner.com/2019/01/no-really-pathlib-is-great/)
+#[derive(ViolationMetadata)]
+pub(crate) struct OsSymlink;
+
+impl Violation for OsSymlink {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Sometimes;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        "`os.symlink` should be replaced by `Path.symlink_to`".to_string()
+    }
+
+    fn fix_title(&self) -> Option<String> {
+        Some("Replace with `Path(...).symlink_to(...)`".to_string())
+    }
+}
+
+/// PTH211
+pub(crate) fn os_symlink(checker: &Checker, call: &ExprCall, segments: &[&str]) {
+    if segments != ["os", "symlink"] {
+        return;
+    }
+
+    // `dir_fd` is not supported by pathlib, so check if there are non-default values.
+    // Signature as of Python 3.13 (https://docs.python.org/3/library/os.html#os.symlink)
+    // ```text
+    //            0    1    2                             3
+    // os.symlink(src, dst, target_is_directory=False, *, dir_fd=None)
+    // ```
+    if is_keyword_only_argument_non_default(&call.arguments, "dir_fd") {
+        return;
+    }
+
+    let range = call.range();
+    let mut diagnostic = checker.report_diagnostic(OsSymlink, call.func.range());
+
+    if !is_fix_os_symlink_enabled(checker.settings()) {
+        return;
+    }
+
+    if call.arguments.len() > 3 {
+        return;
+    }
+
+    if has_unknown_keywords_or_starred_expr(
+        &call.arguments,
+        &["src", "dst", "target_is_directory", "dir_fd"],
+    ) {
+        return;
+    }
+
+    let (Some(src), Some(dst)) = (
+        call.arguments.find_argument_value("src", 0),
+        call.arguments.find_argument_value("dst", 1),
+    ) else {
+        return;
+    };
+
+    let target_is_directory_arg = call.arguments.find_argument_value("target_is_directory", 2);
+
+    if let Some(expr) = &target_is_directory_arg {
+        if expr.as_boolean_literal_expr().is_none() {
+            return;
+        }
+    }
+
+    diagnostic.try_set_fix(|| {
+        let (import_edit, binding) = checker.importer().get_or_import_symbol(
+            &ImportRequest::import("pathlib", "Path"),
+            call.start(),
+            checker.semantic(),
+        )?;
+
+        let applicability = if checker.comment_ranges().intersects(range) {
+            Applicability::Unsafe
+        } else {
+            Applicability::Safe
+        };
+
+        let locator = checker.locator();
+        let src_code = locator.slice(src.range());
+        let dst_code = locator.slice(dst.range());
+
+        let target_is_directory = target_is_directory_arg
+            .and_then(|expr| {
+                let code = locator.slice(expr.range());
+                expr.as_boolean_literal_expr()
+                    .is_none_or(|bl| bl.value)
+                    .then_some(format!(", target_is_directory={code}"))
+            })
+            .unwrap_or_default();
+
+        let replacement = if is_pathlib_path_call(checker, dst) {
+            format!("{dst_code}.symlink_to({src_code}{target_is_directory})")
+        } else {
+            format!("{binding}({dst_code}).symlink_to({src_code}{target_is_directory})")
+        };
+
+        Ok(Fix::applicable_edits(
+            Edit::range_replacement(replacement, range),
+            [import_edit],
+            applicability,
+        ))
+    });
+}

crates/ruff_linter/src/rules/flake8_use_pathlib/rules/replaceable_by_pathlib.rs

@@ -7,9 +7,7 @@ use crate::rules::flake8_use_pathlib::helpers::{
 };
 use crate::rules::flake8_use_pathlib::{
     rules::Glob,
-    violations::{
-        BuiltinOpen, Joiner, OsListdir, OsPathJoin, OsPathSplitext, OsStat, OsSymlink, PyPath,
-    },
+    violations::{BuiltinOpen, Joiner, OsListdir, OsPathJoin, OsPathSplitext, OsStat, PyPath},
 };
 
 pub(crate) fn replaceable_by_pathlib(checker: &Checker, call: &ExprCall) {
@@ -62,20 +60,6 @@ pub(crate) fn replaceable_by_pathlib(checker: &Checker, call: &ExprCall) {
         ),
         // PTH122
         ["os", "path", "splitext"] => checker.report_diagnostic_if_enabled(OsPathSplitext, range),
-        // PTH211
-        ["os", "symlink"] => {
-            // `dir_fd` is not supported by pathlib, so check if there are non-default values.
-            // Signature as of Python 3.13 (https://docs.python.org/3/library/os.html#os.symlink)
-            // ```text
-            //            0    1    2                             3
-            // os.symlink(src, dst, target_is_directory=False, *, dir_fd=None)
-            // ```
-            if is_keyword_only_argument_non_default(&call.arguments, "dir_fd") {
-                return;
-            }
-            checker.report_diagnostic_if_enabled(OsSymlink, range)
-        }
-
         // PTH123
         ["" | "builtins", "open"] => {
             // `closefd` and `opener` are not supported by pathlib, so check if they

crates/ruff_linter/src/rules/flake8_use_pathlib/snapshots/ruff_linter__rules__flake8_use_pathlib__tests__PTH211_PTH211.py.snap

@@ -9,6 +9,7 @@ PTH211 `os.symlink` should be replaced by `Path.symlink_to`
 6 | os.symlink(b"usr/bin/python", b"tmp/python")
 7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
   |
+help: Replace with `Path(...).symlink_to(...)`
 
 PTH211 `os.symlink` should be replaced by `Path.symlink_to`
  --> PTH211.py:6:1
@@ -18,6 +19,7 @@ PTH211 `os.symlink` should be replaced by `Path.symlink_to`
   | ^^^^^^^^^^
 7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
   |
+help: Replace with `Path(...).symlink_to(...)`
 
 PTH211 `os.symlink` should be replaced by `Path.symlink_to`
   --> PTH211.py:9:1
@@ -29,6 +31,7 @@ PTH211 `os.symlink` should be replaced by `Path.symlink_to`
 10 | os.symlink(b"usr/bin/python", b"tmp/python", target_is_directory=True)
 11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
    |
+help: Replace with `Path(...).symlink_to(...)`
 
 PTH211 `os.symlink` should be replaced by `Path.symlink_to`
   --> PTH211.py:10:1
@@ -38,3 +41,58 @@ PTH211 `os.symlink` should be replaced by `Path.symlink_to`
    | ^^^^^^^^^^
 11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
    |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:17:1
+   |
+15 | os.close(fd)
+16 |
+17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+   | ^^^^^^^^^^
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:18:1
+   |
+17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+   | ^^^^^^^^^^
+19 |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:20:1
+   |
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+19 |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+   | ^^^^^^^^^^
+21 |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:22:1
+   |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+21 |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+   | ^^^^^^^^^^
+23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:23:1
+   |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+   | ^^^^^^^^^^
+   |
+help: Replace with `Path(...).symlink_to(...)`

crates/ruff_linter/src/rules/flake8_use_pathlib/snapshots/ruff_linter__rules__flake8_use_pathlib__tests__preview__PTH211_PTH211.py.snap

@@ -0,0 +1,166 @@
+---
+source: crates/ruff_linter/src/rules/flake8_use_pathlib/mod.rs
+---
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+ --> PTH211.py:5:1
+  |
+5 | os.symlink("usr/bin/python", "tmp/python")
+  | ^^^^^^^^^^
+6 | os.symlink(b"usr/bin/python", b"tmp/python")
+7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+  |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+2 2 | from pathlib import Path
+3 3 | 
+4 4 | 
+5   |-os.symlink("usr/bin/python", "tmp/python")
+  5 |+Path("tmp/python").symlink_to("usr/bin/python")
+6 6 | os.symlink(b"usr/bin/python", b"tmp/python")
+7 7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+8 8 | 
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+ --> PTH211.py:6:1
+  |
+5 | os.symlink("usr/bin/python", "tmp/python")
+6 | os.symlink(b"usr/bin/python", b"tmp/python")
+  | ^^^^^^^^^^
+7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+  |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+3 3 | 
+4 4 | 
+5 5 | os.symlink("usr/bin/python", "tmp/python")
+6   |-os.symlink(b"usr/bin/python", b"tmp/python")
+  6 |+Path(b"tmp/python").symlink_to(b"usr/bin/python")
+7 7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+8 8 | 
+9 9 | os.symlink("usr/bin/python", "tmp/python", target_is_directory=True)
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:9:1
+   |
+ 7 | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+ 8 |
+ 9 | os.symlink("usr/bin/python", "tmp/python", target_is_directory=True)
+   | ^^^^^^^^^^
+10 | os.symlink(b"usr/bin/python", b"tmp/python", target_is_directory=True)
+11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+6  6  | os.symlink(b"usr/bin/python", b"tmp/python")
+7  7  | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+8  8  | 
+9     |-os.symlink("usr/bin/python", "tmp/python", target_is_directory=True)
+   9  |+Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)
+10 10 | os.symlink(b"usr/bin/python", b"tmp/python", target_is_directory=True)
+11 11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
+12 12 | 
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:10:1
+   |
+ 9 | os.symlink("usr/bin/python", "tmp/python", target_is_directory=True)
+10 | os.symlink(b"usr/bin/python", b"tmp/python", target_is_directory=True)
+   | ^^^^^^^^^^
+11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+7  7  | Path("tmp/python").symlink_to("usr/bin/python")  # Ok
+8  8  | 
+9  9  | os.symlink("usr/bin/python", "tmp/python", target_is_directory=True)
+10    |-os.symlink(b"usr/bin/python", b"tmp/python", target_is_directory=True)
+   10 |+Path(b"tmp/python").symlink_to(b"usr/bin/python", target_is_directory=True)
+11 11 | Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)  # Ok
+12 12 | 
+13 13 | fd = os.open(".", os.O_RDONLY)
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:17:1
+   |
+15 | os.close(fd)
+16 |
+17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+   | ^^^^^^^^^^
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:18:1
+   |
+17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+   | ^^^^^^^^^^
+19 |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+15 15 | os.close(fd)
+16 16 | 
+17 17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+18    |-os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+   18 |+Path("tmp/python").symlink_to("usr/bin/python")
+19 19 | 
+20 20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+21 21 | 
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:20:1
+   |
+18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+19 |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+   | ^^^^^^^^^^
+21 |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+17 17 | os.symlink(src="usr/bin/python", dst="tmp/python", unknown=True)
+18 18 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=False)
+19 19 | 
+20    |-os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+   20 |+Path("tmp/python").symlink_to("usr/bin/python")
+21 21 | 
+22 22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+23 23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+
+PTH211 [*] `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:22:1
+   |
+20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+21 |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+   | ^^^^^^^^^^
+23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+   |
+help: Replace with `Path(...).symlink_to(...)`
+
+ℹ Safe fix
+19 19 | 
+20 20 | os.symlink(src="usr/bin/python", dst="tmp/python", dir_fd=None)
+21 21 | 
+22    |-os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+   22 |+Path("tmp/python").symlink_to("usr/bin/python", target_is_directory=True)
+23 23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+
+PTH211 `os.symlink` should be replaced by `Path.symlink_to`
+  --> PTH211.py:23:1
+   |
+22 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory=     True    )
+23 | os.symlink("usr/bin/python",  dst="tmp/python", target_is_directory="nonboolean")
+   | ^^^^^^^^^^
+   |
+help: Replace with `Path(...).symlink_to(...)`

crates/ruff_linter/src/rules/flake8_use_pathlib/violations.rs

@@ -310,45 +310,3 @@ impl Violation for OsListdir {
         "Use `pathlib.Path.iterdir()` instead.".to_string()
     }
 }
-
-/// ## What it does
-/// Checks for uses of `os.symlink`.
-///
-/// ## Why is this bad?
-/// `pathlib` offers a high-level API for path manipulation, as compared to
-/// the lower-level API offered by `os.symlink`.
-///
-/// ## Example
-/// ```python
-/// import os
-///
-/// os.symlink("usr/bin/python", "tmp/python", target_is_directory=False)
-/// ```
-///
-/// Use instead:
-/// ```python
-/// from pathlib import Path
-///
-/// Path("tmp/python").symlink_to("usr/bin/python")
-/// ```
-///
-/// ## Known issues
-/// While using `pathlib` can improve the readability and type safety of your code,
-/// it can be less performant than the lower-level alternatives that work directly with strings,
-/// especially on older versions of Python.
-///
-/// ## References
-/// - [Python documentation: `Path.symlink_to`](https://docs.python.org/3/library/pathlib.html#pathlib.Path.symlink_to)
-/// - [PEP 428 – The pathlib module – object-oriented filesystem paths](https://peps.python.org/pep-0428/)
-/// - [Correspondence between `os` and `pathlib`](https://docs.python.org/3/library/pathlib.html#correspondence-to-tools-in-the-os-module)
-/// - [Why you should be using pathlib](https://treyhunner.com/2018/12/why-you-should-be-using-pathlib/)
-/// - [No really, pathlib is great](https://treyhunner.com/2019/01/no-really-pathlib-is-great/)
-#[derive(ViolationMetadata)]
-pub(crate) struct OsSymlink;
-
-impl Violation for OsSymlink {
-    #[derive_message_formats]
-    fn message(&self) -> String {
-        "`os.symlink` should be replaced by `Path.symlink_to`".to_string()
-    }
-}

crates/ruff_linter/src/rules/flynt/helpers.rs

@@ -9,7 +9,7 @@ fn to_interpolated_string_interpolation_element(inner: &Expr) -> ast::Interpolat
         conversion: ConversionFlag::None,
         format_spec: None,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 
@@ -18,7 +18,7 @@ pub(super) fn to_interpolated_string_literal_element(s: &str) -> ast::Interpolat
     ast::InterpolatedStringElement::Literal(ast::InterpolatedStringLiteralElement {
         value: Box::from(s),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     })
 }
 

crates/ruff_linter/src/rules/flynt/rules/static_join_to_fstring.rs

@@ -91,7 +91,7 @@ fn build_fstring(joiner: &str, joinees: &[Expr], flags: FStringFlags) -> Option<
                 .into_boxed_str(),
             flags: flags?,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         return Some(node.into());
     }
@@ -114,7 +114,7 @@ fn build_fstring(joiner: &str, joinees: &[Expr], flags: FStringFlags) -> Option<
     let node = ast::FString {
         elements: f_string_elements.into(),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         flags,
     };
     Some(node.into())

crates/ruff_linter/src/rules/pycodestyle/rules/lambda_assignment.rs

@@ -182,7 +182,7 @@ fn function(
             ExprEllipsisLiteral::default(),
         ))),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     });
     let parameters = lambda.parameters.as_deref().cloned().unwrap_or_default();
     if let Some(annotation) = annotation {
@@ -230,7 +230,7 @@ fn function(
                 returns: Some(Box::new(return_type)),
                 type_params: None,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let generated = checker.generator().stmt(&func);
 
@@ -246,7 +246,7 @@ fn function(
         returns: None,
         type_params: None,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     });
     let generated = checker.generator().stmt(&function);
 

crates/ruff_linter/src/rules/pylint/rules/manual_import_from.rs

@@ -72,11 +72,11 @@ pub(crate) fn manual_from_import(checker: &Checker, stmt: &Stmt, alias: &Alias,
                 name: asname.clone(),
                 asname: None,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }],
             level: 0,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         };
         diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(
             checker.generator().stmt(&node.into()),

crates/ruff_linter/src/rules/pylint/rules/nested_min_max.rs

@@ -147,7 +147,7 @@ fn collect_nested_args(min_max: MinMax, args: &[Expr], semantic: &SemanticModel)
                                 value: Box::new(arg.clone()),
                                 ctx: ast::ExprContext::Load,
                                 range: TextRange::default(),
-                                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             });
                             new_args.push(new_arg);
                             continue;
@@ -204,10 +204,10 @@ pub(crate) fn nested_min_max(
                 args: collect_nested_args(min_max, args, checker.semantic()).into_boxed_slice(),
                 keywords: Box::from(keywords),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             },
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         diagnostic.set_fix(Fix::unsafe_edit(Edit::range_replacement(
             checker.generator().expr(&flattened_expr),

crates/ruff_linter/src/rules/pylint/rules/repeated_equality_comparison.rs

@@ -170,13 +170,13 @@ pub(crate) fn repeated_equality_comparison(checker: &Checker, bool_op: &ast::Exp
                 Expr::Set(ast::ExprSet {
                     elts: comparators.iter().copied().cloned().collect(),
                     range: TextRange::default(),
-                    node_index: AtomicNodeIndex::dummy(),
+                    node_index: AtomicNodeIndex::NONE,
                 })
             } else {
                 Expr::Tuple(ast::ExprTuple {
                     elts: comparators.iter().copied().cloned().collect(),
                     range: TextRange::default(),
-                    node_index: AtomicNodeIndex::dummy(),
+                    node_index: AtomicNodeIndex::NONE,
                     ctx: ExprContext::Load,
                     parenthesized: true,
                 })
@@ -194,12 +194,12 @@ pub(crate) fn repeated_equality_comparison(checker: &Checker, bool_op: &ast::Exp
                             },
                             comparators: Box::from([comparator]),
                             range: bool_op.range(),
-                            node_index: AtomicNodeIndex::dummy(),
+                            node_index: AtomicNodeIndex::NONE,
                         })))
                         .chain(after)
                         .collect(),
                     range: bool_op.range(),
-                    node_index: AtomicNodeIndex::dummy(),
+                    node_index: AtomicNodeIndex::NONE,
                 })),
                 bool_op.range(),
             )));

crates/ruff_linter/src/rules/pylint/rules/unspecified_encoding.rs

@@ -188,7 +188,7 @@ fn generate_keyword_fix(checker: &Checker, call: &ast::ExprCall) -> Fix {
                 value: Box::from("utf-8"),
                 flags: checker.default_string_flags(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }))
         ),
         &call.arguments,

crates/ruff_linter/src/rules/pyupgrade/rules/convert_named_tuple_functional_to_class.rs

@@ -87,7 +87,7 @@ pub(crate) fn convert_named_tuple_functional_to_class(
         // Ex) `NamedTuple("MyType")`
         ([_typename], []) => vec![Stmt::Pass(ast::StmtPass {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })],
         // Ex) `NamedTuple("MyType", [("a", int), ("b", str)])`
         ([_typename, fields], []) => {
@@ -165,7 +165,7 @@ fn create_field_assignment_stmt(field: Name, annotation: &Expr) -> Stmt {
                 id: field,
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
         ),
@@ -173,7 +173,7 @@ fn create_field_assignment_stmt(field: Name, annotation: &Expr) -> Stmt {
         value: None,
         simple: true,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
     .into()
 }
@@ -184,7 +184,7 @@ fn create_fields_from_fields_arg(fields: &Expr) -> Option<Vec<Stmt>> {
     if fields.is_empty() {
         let node = Stmt::Pass(ast::StmtPass {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         Some(vec![node])
     } else {
@@ -236,13 +236,13 @@ fn create_class_def_stmt(typename: &str, body: Vec<Stmt>, base_class: &Expr) ->
             args: Box::from([base_class.clone()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })),
         body,
         type_params: None,
         decorator_list: vec![],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
     .into()
 }

crates/ruff_linter/src/rules/pyupgrade/rules/convert_typed_dict_functional_to_class.rs

@@ -150,7 +150,7 @@ fn create_field_assignment_stmt(field: &str, annotation: &Expr) -> Stmt {
                 id: field.into(),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
         ),
@@ -158,7 +158,7 @@ fn create_field_assignment_stmt(field: &str, annotation: &Expr) -> Stmt {
         value: None,
         simple: true,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
     .into()
 }
@@ -179,13 +179,13 @@ fn create_class_def_stmt(
                 None => Box::from([]),
             },
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })),
         body,
         type_params: None,
         decorator_list: vec![],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
     .into()
 }
@@ -194,7 +194,7 @@ fn fields_from_dict_literal(items: &[ast::DictItem]) -> Option<Vec<Stmt>> {
     if items.is_empty() {
         let node = Stmt::Pass(ast::StmtPass {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         Some(vec![node])
     } else {
@@ -228,7 +228,7 @@ fn fields_from_dict_call(func: &Expr, keywords: &[Keyword]) -> Option<Vec<Stmt>>
     if keywords.is_empty() {
         let node = Stmt::Pass(ast::StmtPass {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         Some(vec![node])
     } else {
@@ -241,7 +241,7 @@ fn fields_from_keywords(keywords: &[Keyword]) -> Option<Vec<Stmt>> {
     if keywords.is_empty() {
         let node = Stmt::Pass(ast::StmtPass {
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         return Some(vec![node]);
     }
@@ -282,7 +282,7 @@ fn match_fields_and_total(arguments: &Arguments) -> Option<(Vec<Stmt>, Option<&K
         ([_typename], []) => {
             let node = Stmt::Pass(ast::StmtPass {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             Some((vec![node], None))
         }

crates/ruff_linter/src/rules/pyupgrade/rules/native_literals.rs

@@ -39,27 +39,27 @@ impl LiteralType {
             LiteralType::Str => ast::StringLiteral {
                 value: Box::default(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 flags: checker.default_string_flags(),
             }
             .into(),
             LiteralType::Bytes => ast::BytesLiteral {
                 value: Box::default(),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 flags: checker.default_bytes_flags(),
             }
             .into(),
             LiteralType::Int => ast::ExprNumberLiteral {
                 value: ast::Number::Int(Int::from(0u8)),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
             LiteralType::Float => ast::ExprNumberLiteral {
                 value: ast::Number::Float(0.0),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
             LiteralType::Bool => ast::ExprBooleanLiteral::default().into(),

crates/ruff_linter/src/rules/pyupgrade/rules/os_error_alias.rs

@@ -116,7 +116,7 @@ fn tuple_diagnostic(checker: &Checker, tuple: &ast::ExprTuple, aliases: &[&Expr]
                 id: Name::new_static("OSError"),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             };
             remaining.insert(0, node.into());
         }
@@ -128,7 +128,7 @@ fn tuple_diagnostic(checker: &Checker, tuple: &ast::ExprTuple, aliases: &[&Expr]
                 elts: remaining,
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 parenthesized: true,
             };
             format!("({})", checker.generator().expr(&node.into()))

crates/ruff_linter/src/rules/pyupgrade/rules/pep695/mod.rs

@@ -140,14 +140,14 @@ impl<'a> From<&'a TypeVar<'a>> for TypeParam {
             TypeParamKind::TypeVar => {
                 TypeParam::TypeVar(TypeParamTypeVar {
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     name: Identifier::new(*name, TextRange::default()),
                     bound: match restriction {
                         Some(TypeVarRestriction::Bound(bound)) => Some(Box::new((*bound).clone())),
                         Some(TypeVarRestriction::Constraint(constraints)) => {
                             Some(Box::new(Expr::Tuple(ast::ExprTuple {
                                 range: TextRange::default(),
-                                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                 elts: constraints.iter().map(|expr| (*expr).clone()).collect(),
                                 ctx: ast::ExprContext::Load,
                                 parenthesized: true,
@@ -156,17 +156,17 @@ impl<'a> From<&'a TypeVar<'a>> for TypeParam {
                         Some(TypeVarRestriction::AnyStr) => {
                             Some(Box::new(Expr::Tuple(ast::ExprTuple {
                                 range: TextRange::default(),
-                                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                 elts: vec![
                                     Expr::Name(ExprName {
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                         id: Name::from("str"),
                                         ctx: ast::ExprContext::Load,
                                     }),
                                     Expr::Name(ExprName {
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                         id: Name::from("bytes"),
                                         ctx: ast::ExprContext::Load,
                                     }),
@@ -184,13 +184,13 @@ impl<'a> From<&'a TypeVar<'a>> for TypeParam {
             }
             TypeParamKind::TypeVarTuple => TypeParam::TypeVarTuple(TypeParamTypeVarTuple {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 name: Identifier::new(*name, TextRange::default()),
                 default: None,
             }),
             TypeParamKind::ParamSpec => TypeParam::ParamSpec(TypeParamParamSpec {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 name: Identifier::new(*name, TextRange::default()),
                 default: None,
             }),

crates/ruff_linter/src/rules/pyupgrade/rules/timeout_error_alias.rs

@@ -130,7 +130,7 @@ fn tuple_diagnostic(checker: &Checker, tuple: &ast::ExprTuple, aliases: &[&Expr]
                 id: Name::new_static("TimeoutError"),
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             };
             remaining.insert(0, node.into());
         }
@@ -142,7 +142,7 @@ fn tuple_diagnostic(checker: &Checker, tuple: &ast::ExprTuple, aliases: &[&Expr]
                 elts: remaining,
                 ctx: ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 parenthesized: true,
             };
             format!("({})", checker.generator().expr(&node.into()))

crates/ruff_linter/src/rules/pyupgrade/rules/unnecessary_default_type_args.rs

@@ -127,13 +127,13 @@ pub(crate) fn unnecessary_default_type_args(checker: &Checker, expr: &Expr) {
                             elts: valid_elts,
                             ctx: ast::ExprContext::Load,
                             range: TextRange::default(),
-                            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                             parenthesized: true,
                         })
                     }),
                     ctx: ast::ExprContext::Load,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 })),
             expr.range(),
         ),

crates/ruff_linter/src/rules/refurb/helpers.rs

@@ -17,7 +17,7 @@ pub(super) fn generate_method_call(name: Name, method: &str, generator: Generato
         id: name,
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Construct `name.method`.
     let attr = ast::ExprAttribute {
@@ -25,7 +25,7 @@ pub(super) fn generate_method_call(name: Name, method: &str, generator: Generato
         attr: ast::Identifier::new(method.to_string(), TextRange::default()),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Make it into a call `name.method()`
     let call = ast::ExprCall {
@@ -34,16 +34,16 @@ pub(super) fn generate_method_call(name: Name, method: &str, generator: Generato
             args: Box::from([]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // And finally, turn it into a statement.
     let stmt = ast::StmtExpr {
         value: Box::new(call.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.stmt(&stmt.into())
 }
@@ -69,7 +69,7 @@ pub(super) fn replace_with_identity_check(
         ops: [op].into(),
         comparators: [ast::ExprNoneLiteral::default().into()].into(),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     });
 
     let new_content = generator.expr(&new_expr);

crates/ruff_linter/src/rules/refurb/rules/check_and_remove_from_set.rs

@@ -185,7 +185,7 @@ fn make_suggestion(set: &ast::ExprName, element: &Expr, generator: Generator) ->
         attr: ast::Identifier::new("discard".to_string(), TextRange::default()),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Make the actual call `set.discard(element)`
     let call = ast::ExprCall {
@@ -194,16 +194,16 @@ fn make_suggestion(set: &ast::ExprName, element: &Expr, generator: Generator) ->
             args: Box::from([element.clone()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // And finally, turn it into a statement.
     let stmt = ast::StmtExpr {
         value: Box::new(call.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.stmt(&stmt.into())
 }

crates/ruff_linter/src/rules/refurb/rules/read_whole_file.rs

@@ -130,7 +130,7 @@ fn make_suggestion(open: &FileOpen<'_>, generator: Generator) -> SourceCodeSnipp
         id: open.mode.pathlib_method(),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let call = ast::ExprCall {
         func: Box::new(name.into()),
@@ -138,10 +138,10 @@ fn make_suggestion(open: &FileOpen<'_>, generator: Generator) -> SourceCodeSnipp
             args: Box::from([]),
             keywords: open.keywords.iter().copied().cloned().collect(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     SourceCodeSnippet::from_str(&generator.expr(&call.into()))
 }

crates/ruff_linter/src/rules/refurb/rules/reimplemented_starmap.rs

@@ -298,7 +298,7 @@ fn construct_starmap_call(starmap_binding: Name, iter: &Expr, func: &Expr) -> as
         id: starmap_binding,
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     ast::ExprCall {
         func: Box::new(starmap.into()),
@@ -306,10 +306,10 @@ fn construct_starmap_call(starmap_binding: Name, iter: &Expr, func: &Expr) -> as
             args: Box::from([func.clone(), iter.clone()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
 }
 
@@ -319,7 +319,7 @@ fn wrap_with_call_to(call: ast::ExprCall, func_name: Name) -> ast::ExprCall {
         id: func_name,
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     ast::ExprCall {
         func: Box::new(name.into()),
@@ -327,10 +327,10 @@ fn wrap_with_call_to(call: ast::ExprCall, func_name: Name) -> ast::ExprCall {
             args: Box::from([call.into()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     }
 }
 

crates/ruff_linter/src/rules/refurb/rules/repeated_append.rs

@@ -342,7 +342,7 @@ fn make_suggestion(group: &AppendGroup, generator: Generator) -> String {
         elts,
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         parenthesized: true,
     };
     // Make `var.extend`.
@@ -352,7 +352,7 @@ fn make_suggestion(group: &AppendGroup, generator: Generator) -> String {
         attr: ast::Identifier::new("extend".to_string(), TextRange::default()),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Make the actual call `var.extend((elt1, elt2, ..., eltN))`
     let call = ast::ExprCall {
@@ -361,16 +361,16 @@ fn make_suggestion(group: &AppendGroup, generator: Generator) -> String {
             args: Box::from([tuple.into()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // And finally, turn it into a statement.
     let stmt = ast::StmtExpr {
         value: Box::new(call.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.stmt(&stmt.into())
 }

crates/ruff_linter/src/rules/refurb/rules/unnecessary_enumerate.rs

@@ -232,7 +232,7 @@ fn generate_range_len_call(name: Name, generator: Generator) -> String {
         id: name,
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Construct `len(name)`.
     let len = ast::ExprCall {
@@ -241,7 +241,7 @@ fn generate_range_len_call(name: Name, generator: Generator) -> String {
                 id: Name::new_static("len"),
                 ctx: ast::ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
         ),
@@ -249,10 +249,10 @@ fn generate_range_len_call(name: Name, generator: Generator) -> String {
             args: Box::from([var.into()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Construct `range(len(name))`.
     let range = ast::ExprCall {
@@ -261,7 +261,7 @@ fn generate_range_len_call(name: Name, generator: Generator) -> String {
                 id: Name::new_static("range"),
                 ctx: ast::ExprContext::Load,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }
             .into(),
         ),
@@ -269,16 +269,16 @@ fn generate_range_len_call(name: Name, generator: Generator) -> String {
             args: Box::from([len.into()]),
             keywords: Box::from([]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // And finally, turn it into a statement.
     let stmt = ast::StmtExpr {
         value: Box::new(range.into()),
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.stmt(&stmt.into())
 }

crates/ruff_linter/src/rules/refurb/rules/write_whole_file.rs

@@ -148,7 +148,7 @@ fn make_suggestion(open: &FileOpen<'_>, arg: &Expr, generator: Generator) -> Sou
         id: open.mode.pathlib_method(),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let mut arg = arg.clone();
     relocate_expr(&mut arg, TextRange::default());
@@ -158,10 +158,10 @@ fn make_suggestion(open: &FileOpen<'_>, arg: &Expr, generator: Generator) -> Sou
             args: Box::new([arg]),
             keywords: open.keywords.iter().copied().cloned().collect(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         },
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     SourceCodeSnippet::from_str(&generator.expr(&call.into()))
 }

crates/ruff_linter/src/rules/ruff/rules/assert_with_print_message.rs

@@ -68,7 +68,7 @@ pub(crate) fn assert_with_print_message(checker: &Checker, stmt: &ast::StmtAsser
                     test: stmt.test.clone(),
                     msg: print_arguments::to_expr(&call.arguments, checker).map(Box::new),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 })),
                 // We have to replace the entire statement,
                 // as the `print` could be empty and thus `call.range()`
@@ -114,7 +114,7 @@ mod print_arguments {
                     InterpolatedStringElement::Literal(InterpolatedStringLiteralElement {
                         value: part.value.clone(),
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     })
                 })
                 .collect(),
@@ -131,7 +131,7 @@ mod print_arguments {
                     conversion: ConversionFlag::None,
                     format_spec: None,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 },
             )],
         }
@@ -154,7 +154,7 @@ mod print_arguments {
                     value: literal.value.clone(),
                     flags,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 });
                 Some(acc)
             } else {
@@ -212,7 +212,7 @@ mod print_arguments {
             value: combined_string.into(),
             flags,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         }))
     }
 
@@ -246,10 +246,10 @@ mod print_arguments {
                 elements: InterpolatedStringElements::from(fstring_elements),
                 flags,
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             }),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         }))
     }
 
@@ -285,7 +285,7 @@ mod print_arguments {
                 vec![InterpolatedStringElement::Literal(
                     InterpolatedStringLiteralElement {
                         range: TextRange::default(),
-                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                         value: " ".into(),
                     },
                 )]

crates/ruff_linter/src/rules/ruff/rules/collection_literal_concatenation.rs

@@ -78,7 +78,7 @@ fn make_splat_elts(
         value: Box::from(splat_element.clone()),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     let splat = node.into();
     if splat_at_left {
@@ -166,14 +166,14 @@ fn concatenate_expressions(expr: &Expr) -> Option<(Expr, Type)> {
             elts: new_elts,
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         }
         .into(),
         Type::Tuple => ast::ExprTuple {
             elts: new_elts,
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             parenthesized: true,
         }
         .into(),

crates/ruff_linter/src/rules/ruff/rules/default_factory_kwarg.rs

@@ -123,7 +123,8 @@ fn is_non_callable_value(value: &Expr) -> bool {
             | Expr::SetComp(_)
             | Expr::DictComp(_)
             | Expr::Generator(_)
-            | Expr::FString(_))
+            | Expr::FString(_)
+            | Expr::TString(_))
 }
 
 /// Generate an [`Expr`] to replace `defaultdict(default_factory=callable)` with

crates/ruff_linter/src/rules/ruff/rules/implicit_optional.rs

@@ -140,7 +140,7 @@ fn generate_fix(checker: &Checker, conversion_type: ConversionType, expr: &Expr)
                 op: Operator::BitOr,
                 right: Box::new(Expr::NoneLiteral(ast::ExprNoneLiteral::default())),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             });
             let content = checker.generator().expr(&new_expr);
             let edit = Edit::range_replacement(content, expr.range());
@@ -160,12 +160,12 @@ fn generate_fix(checker: &Checker, conversion_type: ConversionType, expr: &Expr)
             let (import_edit, binding) = importer.import(expr.start())?;
             let new_expr = Expr::Subscript(ast::ExprSubscript {
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 value: Box::new(Expr::Name(ast::ExprName {
                     id: Name::new(binding),
                     ctx: ast::ExprContext::Store,
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 })),
                 slice: Box::new(expr.clone()),
                 ctx: ast::ExprContext::Load,

crates/ruff_linter/src/rules/ruff/rules/legacy_form_pytest_raises.rs

@@ -245,16 +245,16 @@ fn generate_with_statement(
         });
 
     let context_call = ast::ExprCall {
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
         range: TextRange::default(),
         func: legacy_call.func.clone(),
         arguments: ast::Arguments {
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range: TextRange::default(),
             args: expected.cloned().as_slice().into(),
             keywords: match_arg
                 .map(|expr| ast::Keyword {
-                    node_index: AtomicNodeIndex::dummy(),
+                    node_index: AtomicNodeIndex::NONE,
                     // Take range from the original expression so that the keyword
                     // argument is generated after positional arguments
                     range: expr.range(),
@@ -267,11 +267,11 @@ fn generate_with_statement(
     };
 
     let func_call = ast::ExprCall {
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
         range: TextRange::default(),
         func: Box::new(func.clone()),
         arguments: ast::Arguments {
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range: TextRange::default(),
             args: func_args.into(),
             keywords: func_keywords.into(),
@@ -280,25 +280,25 @@ fn generate_with_statement(
 
     let body = if let Some(assign_targets) = assign_targets {
         Stmt::Assign(ast::StmtAssign {
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range: TextRange::default(),
             targets: assign_targets.to_vec(),
             value: Box::new(func_call.into()),
         })
     } else {
         Stmt::Expr(StmtExpr {
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range: TextRange::default(),
             value: Box::new(func_call.into()),
         })
     };
 
     Some(StmtWith {
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
         range: TextRange::default(),
         is_async: false,
         items: vec![WithItem {
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range: TextRange::default(),
             context_expr: context_call.into(),
             optional_vars: optional_vars.map(|var| Box::new(var.clone())),

crates/ruff_linter/src/rules/ruff/rules/mutable_fromkeys_value.rs

@@ -102,7 +102,7 @@ fn generate_dict_comprehension(keys: &Expr, value: &Expr, generator: Generator)
         id: Name::new_static("key"),
         ctx: ast::ExprContext::Load,
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     // Construct `key in keys`.
     let comp = ast::Comprehension {
@@ -110,7 +110,7 @@ fn generate_dict_comprehension(keys: &Expr, value: &Expr, generator: Generator)
         iter: keys.clone(),
         ifs: vec![],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         is_async: false,
     };
     // Construct the dict comprehension.
@@ -119,7 +119,7 @@ fn generate_dict_comprehension(keys: &Expr, value: &Expr, generator: Generator)
         value: Box::new(value.clone()),
         generators: vec![comp],
         range: TextRange::default(),
-        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
     };
     generator.expr(&dict_comp.into())
 }

crates/ruff_linter/src/rules/ruff/rules/never_union.rs

@@ -164,12 +164,12 @@ pub(crate) fn never_union(checker: &Checker, expr: &Expr) {
                                         elts: rest,
                                         ctx: ast::ExprContext::Load,
                                         range: TextRange::default(),
-                                        node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                        node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                         parenthesized: true,
                                     })),
                                     ctx: ast::ExprContext::Load,
                                     range: TextRange::default(),
-                                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                                 }))
                         },
                         expr.range(),

crates/ruff_linter/src/rules/ruff/rules/unnecessary_literal_within_deque_call.rs

@@ -103,6 +103,7 @@ pub(crate) fn unnecessary_literal_within_deque_call(checker: &Checker, deque: &a
         Expr::StringLiteral(string) => string.value.is_empty(),
         Expr::BytesLiteral(bytes) => bytes.value.is_empty(),
         Expr::FString(fstring) => fstring.value.is_empty_literal(),
+        Expr::TString(tstring) => tstring.value.is_empty_iterable(),
         _ => false,
     };
     if !is_empty_literal {

crates/ruff_linter/src/rules/ruff/rules/unnecessary_nested_literal.rs

@@ -116,14 +116,14 @@ pub(crate) fn unnecessary_nested_literal<'a>(checker: &Checker, literal_expr: &'
                 Expr::Tuple(ExprTuple {
                     elts: nodes.into_iter().cloned().collect(),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                     ctx: ExprContext::Load,
                     parenthesized: false,
                 })
             }),
             value: subscript.value.clone(),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         });
         let fix = Fix::applicable_edit(

crates/ruff_linter/src/rules/ruff/rules/unnecessary_regular_expression.rs

@@ -303,7 +303,7 @@ impl<'a> ReFunc<'a> {
                     op: UnaryOp::Not,
                     operand: Box::new(expr),
                     range: TextRange::default(),
-                    node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                    node_index: ruff_python_ast::AtomicNodeIndex::NONE,
                 });
                 Some(negated_expr)
             }
@@ -327,7 +327,7 @@ impl<'a> ReFunc<'a> {
             ops: Box::new([op]),
             comparators: Box::new([right.clone()]),
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })
     }
 
@@ -339,7 +339,7 @@ impl<'a> ReFunc<'a> {
             attr: Identifier::new(method, TextRange::default()),
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         });
         Expr::Call(ExprCall {
             func: Box::new(method),
@@ -347,10 +347,10 @@ impl<'a> ReFunc<'a> {
                 args: args.into_boxed_slice(),
                 keywords: Box::new([]),
                 range: TextRange::default(),
-                node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+                node_index: ruff_python_ast::AtomicNodeIndex::NONE,
             },
             range: TextRange::default(),
-            node_index: ruff_python_ast::AtomicNodeIndex::dummy(),
+            node_index: ruff_python_ast::AtomicNodeIndex::NONE,
         })
     }
 }

crates/ruff_linter/src/rules/ruff/snapshots/ruff_linter__rules__ruff__tests__RUF037_RUF037.py.snap

@@ -383,3 +383,42 @@ help: Replace with `deque()`
 101 101 | deque("abc") # OK
 102 102 | deque(b"abc") # OK
 103 103 | deque(f"" "a")  # OK
+
+RUF037 [*] Unnecessary empty iterable within a deque call
+   --> RUF037.py:107:1
+    |
+106 | # https://github.com/astral-sh/ruff/issues/19951
+107 | deque(t"")
+    | ^^^^^^^^^^
+108 | deque(t""  t"")
+109 | deque(t"{""}") # OK
+    |
+help: Replace with `deque()`
+
+ℹ Safe fix
+104 104 | deque(f"{x}" "")  # OK
+105 105 | 
+106 106 | # https://github.com/astral-sh/ruff/issues/19951
+107     |-deque(t"")
+    107 |+deque()
+108 108 | deque(t""  t"")
+109 109 | deque(t"{""}") # OK
+
+RUF037 [*] Unnecessary empty iterable within a deque call
+   --> RUF037.py:108:1
+    |
+106 | # https://github.com/astral-sh/ruff/issues/19951
+107 | deque(t"")
+108 | deque(t""  t"")
+    | ^^^^^^^^^^^^^^^
+109 | deque(t"{""}") # OK
+    |
+help: Replace with `deque()`
+
+ℹ Safe fix
+105 105 | 
+106 106 | # https://github.com/astral-sh/ruff/issues/19951
+107 107 | deque(t"")
+108     |-deque(t""  t"")
+    108 |+deque()
+109 109 | deque(t"{""}") # OK

crates/ruff_linter/src/test.rs

@@ -2,6 +2,7 @@
 //! Helper functions for the tests of rule implementations.
 
 use std::borrow::Cow;
+use std::fmt;
 use std::path::Path;
 
 #[cfg(not(fuzzing))]
@@ -32,6 +33,85 @@ use crate::source_kind::SourceKind;
 use crate::{Applicability, FixAvailability};
 use crate::{Locator, directives};
 
+/// Represents the difference between two diagnostic runs.
+#[derive(Debug)]
+pub(crate) struct DiagnosticsDiff {
+    /// Diagnostics that were removed (present in 'before' but not in 'after')
+    removed: Vec<Diagnostic>,
+    /// Diagnostics that were added (present in 'after' but not in 'before')
+    added: Vec<Diagnostic>,
+    /// Settings used before the change
+    settings_before: LinterSettings,
+    /// Settings used after the change
+    settings_after: LinterSettings,
+}
+
+impl fmt::Display for DiagnosticsDiff {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(f, "--- Linter settings ---")?;
+        let settings_before_str = format!("{}", self.settings_before);
+        let settings_after_str = format!("{}", self.settings_after);
+        let diff = similar::TextDiff::from_lines(&settings_before_str, &settings_after_str);
+        for change in diff.iter_all_changes() {
+            match change.tag() {
+                similar::ChangeTag::Delete => write!(f, "-{change}")?,
+                similar::ChangeTag::Insert => write!(f, "+{change}")?,
+                similar::ChangeTag::Equal => (),
+            }
+        }
+        writeln!(f)?;
+
+        writeln!(f, "--- Summary ---")?;
+        writeln!(f, "Removed: {}", self.removed.len())?;
+        writeln!(f, "Added: {}", self.added.len())?;
+        writeln!(f)?;
+
+        if !self.removed.is_empty() {
+            writeln!(f, "--- Removed ---")?;
+            for diagnostic in &self.removed {
+                writeln!(f, "{}", print_messages(std::slice::from_ref(diagnostic)))?;
+            }
+            writeln!(f)?;
+        }
+
+        if !self.added.is_empty() {
+            writeln!(f, "--- Added ---")?;
+            for diagnostic in &self.added {
+                writeln!(f, "{}", print_messages(std::slice::from_ref(diagnostic)))?;
+            }
+            writeln!(f)?;
+        }
+
+        Ok(())
+    }
+}
+
+/// Compare two sets of diagnostics and return the differences
+fn diff_diagnostics(
+    before: Vec<Diagnostic>,
+    after: Vec<Diagnostic>,
+    settings_before: &LinterSettings,
+    settings_after: &LinterSettings,
+) -> DiagnosticsDiff {
+    let mut removed = Vec::new();
+    let mut added = after;
+
+    for old_diag in before {
+        let Some(pos) = added.iter().position(|diag| diag == &old_diag) else {
+            removed.push(old_diag);
+            continue;
+        };
+        added.remove(pos);
+    }
+
+    DiagnosticsDiff {
+        removed,
+        added,
+        settings_before: settings_before.clone(),
+        settings_after: settings_after.clone(),
+    }
+}
+
 #[cfg(not(fuzzing))]
 pub(crate) fn test_resource_path(path: impl AsRef<Path>) -> std::path::PathBuf {
     Path::new("./resources/test/").join(path)
@@ -49,6 +129,30 @@ pub(crate) fn test_path(
     Ok(test_contents(&source_kind, &path, settings).0)
 }
 
+/// Test a file with two different settings and return the differences
+#[cfg(not(fuzzing))]
+pub(crate) fn test_path_with_settings_diff(
+    path: impl AsRef<Path>,
+    settings_before: &LinterSettings,
+    settings_after: &LinterSettings,
+) -> Result<DiagnosticsDiff> {
+    assert!(
+        format!("{settings_before}") != format!("{settings_after}"),
+        "Settings must be different for differential testing"
+    );
+
+    let diagnostics_before = test_path(&path, settings_before)?;
+    let diagnostic_after = test_path(&path, settings_after)?;
+
+    let diff = diff_diagnostics(
+        diagnostics_before,
+        diagnostic_after,
+        settings_before,
+        settings_after,
+    );
+    Ok(diff)
+}
+
 #[cfg(not(fuzzing))]
 pub(crate) struct TestedNotebook {
     pub(crate) diagnostics: Vec<Diagnostic>,
@@ -400,3 +504,59 @@ macro_rules! assert_diagnostics {
         });
     }};
 }
+
+#[macro_export]
+macro_rules! assert_diagnostics_diff {
+    ($snapshot:expr, $path:expr, $settings_before:expr, $settings_after:expr) => {{
+        let diff = $crate::test::test_path_with_settings_diff($path, $settings_before, $settings_after)?;
+        insta::with_settings!({ omit_expression => true }, {
+            insta::assert_snapshot!($snapshot, format!("{}", diff));
+        });
+    }};
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_diff_diagnostics() -> Result<()> {
+        use crate::codes::Rule;
+        use ruff_db::diagnostic::{DiagnosticId, LintName};
+
+        let settings_before = LinterSettings::for_rule(Rule::Print);
+        let settings_after = LinterSettings::for_rule(Rule::UnusedImport);
+
+        let test_code = r#"
+import sys
+import unused_module
+
+def main():
+    print(sys.version)
+"#;
+
+        let temp_dir = std::env::temp_dir();
+        let test_file = temp_dir.join("test_diff.py");
+        std::fs::write(&test_file, test_code)?;
+
+        let diff =
+            super::test_path_with_settings_diff(&test_file, &settings_before, &settings_after)?;
+
+        assert_eq!(diff.removed.len(), 1, "Should remove 1 print diagnostic");
+        assert_eq!(
+            diff.removed[0].id(),
+            DiagnosticId::Lint(LintName::of("print")),
+            "Should remove the print diagnostic"
+        );
+        assert_eq!(diff.added.len(), 1, "Should add 1 unused import diagnostic");
+        assert_eq!(
+            diff.added[0].id(),
+            DiagnosticId::Lint(LintName::of("unused-import")),
+            "Should add the unused import diagnostic"
+        );
+
+        std::fs::remove_file(test_file)?;
+
+        Ok(())
+    }
+}

crates/ruff_python_ast/src/helpers.rs

@@ -1489,7 +1489,7 @@ pub fn pep_604_optional(expr: &Expr) -> Expr {
         op: Operator::BitOr,
         right: Box::new(Expr::NoneLiteral(ast::ExprNoneLiteral::default())),
         range: TextRange::default(),
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
     }
     .into()
 }
@@ -1501,7 +1501,7 @@ pub fn pep_604_union(elts: &[Expr]) -> Expr {
             elts: vec![],
             ctx: ExprContext::Load,
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             parenthesized: true,
         }),
         [Expr::Tuple(ast::ExprTuple { elts, .. })] => pep_604_union(elts),
@@ -1511,7 +1511,7 @@ pub fn pep_604_union(elts: &[Expr]) -> Expr {
             op: Operator::BitOr,
             right: Box::new(pep_604_union(std::slice::from_ref(elt))),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         }),
     }
 }
@@ -1522,13 +1522,13 @@ pub fn typing_optional(elt: Expr, binding: Name) -> Expr {
         value: Box::new(Expr::Name(ast::ExprName {
             id: binding,
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         })),
         slice: Box::new(elt),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
     })
 }
 
@@ -1541,19 +1541,19 @@ pub fn typing_union(elts: &[Expr], binding: Name) -> Expr {
         value: Box::new(Expr::Name(ast::ExprName {
             id: binding,
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         })),
         slice: Box::new(Expr::Tuple(ast::ExprTuple {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             elts: elts.to_vec(),
             ctx: ExprContext::Load,
             parenthesized: false,
         })),
         ctx: ExprContext::Load,
         range: TextRange::default(),
-        node_index: AtomicNodeIndex::dummy(),
+        node_index: AtomicNodeIndex::NONE,
     })
 }
 
@@ -1686,34 +1686,34 @@ mod tests {
         let name = Expr::Name(ExprName {
             id: "x".into(),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             ctx: ExprContext::Load,
         });
         let constant_one = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::from(1u8)),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
         let constant_two = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::from(2u8)),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
         let constant_three = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::from(3u8)),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
         let type_var_one = TypeParam::TypeVar(TypeParamTypeVar {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             bound: Some(Box::new(constant_one.clone())),
             default: None,
             name: Identifier::new("x", TextRange::default()),
         });
         let type_var_two = TypeParam::TypeVar(TypeParamTypeVar {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             bound: None,
             default: Some(Box::new(constant_two.clone())),
             name: Identifier::new("x", TextRange::default()),
@@ -1723,11 +1723,11 @@ mod tests {
             type_params: Some(Box::new(TypeParams {
                 type_params: vec![type_var_one, type_var_two],
                 range: TextRange::default(),
-                node_index: AtomicNodeIndex::dummy(),
+                node_index: AtomicNodeIndex::NONE,
             })),
             value: Box::new(constant_three.clone()),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
         assert!(!any_over_stmt(&type_alias, &|expr| {
             seen.borrow_mut().push(expr.clone());
@@ -1743,7 +1743,7 @@ mod tests {
     fn any_over_type_param_type_var() {
         let type_var_no_bound = TypeParam::TypeVar(TypeParamTypeVar {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             bound: None,
             default: None,
             name: Identifier::new("x", TextRange::default()),
@@ -1753,12 +1753,12 @@ mod tests {
         let constant = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::ONE),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
 
         let type_var_with_bound = TypeParam::TypeVar(TypeParamTypeVar {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             bound: Some(Box::new(constant.clone())),
             default: None,
             name: Identifier::new("x", TextRange::default()),
@@ -1776,7 +1776,7 @@ mod tests {
 
         let type_var_with_default = TypeParam::TypeVar(TypeParamTypeVar {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             default: Some(Box::new(constant.clone())),
             bound: None,
             name: Identifier::new("x", TextRange::default()),
@@ -1797,7 +1797,7 @@ mod tests {
     fn any_over_type_param_type_var_tuple() {
         let type_var_tuple = TypeParam::TypeVarTuple(TypeParamTypeVarTuple {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             name: Identifier::new("x", TextRange::default()),
             default: None,
         });
@@ -1809,12 +1809,12 @@ mod tests {
         let constant = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::ONE),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
 
         let type_var_tuple_with_default = TypeParam::TypeVarTuple(TypeParamTypeVarTuple {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             default: Some(Box::new(constant.clone())),
             name: Identifier::new("x", TextRange::default()),
         });
@@ -1834,7 +1834,7 @@ mod tests {
     fn any_over_type_param_param_spec() {
         let type_param_spec = TypeParam::ParamSpec(TypeParamParamSpec {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             name: Identifier::new("x", TextRange::default()),
             default: None,
         });
@@ -1846,12 +1846,12 @@ mod tests {
         let constant = Expr::NumberLiteral(ExprNumberLiteral {
             value: Number::Int(Int::ONE),
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         });
 
         let param_spec_with_default = TypeParam::TypeVarTuple(TypeParamTypeVarTuple {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             default: Some(Box::new(constant.clone())),
             name: Identifier::new("x", TextRange::default()),
         });

crates/ruff_python_ast/src/node_index.rs

@@ -1,3 +1,4 @@
+use std::num::NonZeroU32;
 use std::sync::atomic::{AtomicU32, Ordering};
 
 /// An AST node that has an index.
@@ -16,64 +17,83 @@ where
 }
 
 /// A unique index for a node within an AST.
-///
-/// This type is interiorly mutable to allow assigning node indices
-/// on-demand after parsing.
-#[derive(Default)]
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Hash)]
 #[cfg_attr(feature = "get-size", derive(get_size2::GetSize))]
-pub struct AtomicNodeIndex(AtomicU32);
-
-impl AtomicNodeIndex {
-    /// Returns a placeholder `AtomicNodeIndex`.
-    pub const fn dummy() -> AtomicNodeIndex {
-        AtomicNodeIndex(AtomicU32::new(u32::MAX))
-    }
-
-    /// Load the current value of the `AtomicNodeIndex`.
-    pub fn load(&self) -> NodeIndex {
-        NodeIndex(self.0.load(Ordering::Relaxed))
-    }
-
-    /// Set the value of the `AtomicNodeIndex`.
-    pub fn set(&self, value: u32) {
-        self.0.store(value, Ordering::Relaxed);
-    }
-}
-
-/// A unique index for a node within an AST.
-#[derive(PartialEq, Eq, Debug, PartialOrd, Ord, Clone, Copy, Hash)]
-#[cfg_attr(feature = "get-size", derive(get_size2::GetSize))]
-pub struct NodeIndex(u32);
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+pub struct NodeIndex(NonZeroU32);
 
 impl NodeIndex {
-    pub fn as_usize(self) -> usize {
-        self.0 as _
-    }
+    /// A placeholder `NodeIndex`.
+    pub const NONE: NodeIndex = NodeIndex(NonZeroU32::new(NodeIndex::_NONE).unwrap());
 
-    pub fn as_u32(self) -> u32 {
-        self.0
+    // Note that the index `u32::MAX` is reserved for the `NonZeroU32` niche, and
+    // this placeholder also reserves the second highest index.
+    const _NONE: u32 = u32::MAX - 1;
+
+    /// Returns the index as a `u32`. or `None` for `NodeIndex::NONE`.
+    pub fn as_u32(self) -> Option<u32> {
+        if self == NodeIndex::NONE {
+            None
+        } else {
+            Some(self.0.get() - 1)
+        }
     }
 }
 
 impl From<u32> for NodeIndex {
     fn from(value: u32) -> Self {
-        NodeIndex(value)
+        match NonZeroU32::new(value + 1).map(NodeIndex) {
+            None | Some(NodeIndex::NONE) => panic!("exceeded maximum `NodeIndex`"),
+            Some(index) => index,
+        }
     }
 }
 
-impl From<u32> for AtomicNodeIndex {
-    fn from(value: u32) -> Self {
-        AtomicNodeIndex(AtomicU32::from(value))
+impl std::fmt::Debug for NodeIndex {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        if *self == Self::NONE {
+            f.debug_tuple("NodeIndex(None)").finish()
+        } else {
+            f.debug_tuple("NodeIndex").field(&self.0).finish()
+        }
+    }
+}
+
+/// A unique index for a node within an AST.
+///
+/// This type is interiorly mutable to allow assigning node indices
+/// on-demand after parsing.
+#[cfg_attr(feature = "get-size", derive(get_size2::GetSize))]
+pub struct AtomicNodeIndex(AtomicU32);
+
+#[allow(clippy::declare_interior_mutable_const)]
+impl AtomicNodeIndex {
+    /// A placeholder `AtomicNodeIndex`.
+    pub const NONE: AtomicNodeIndex = AtomicNodeIndex(AtomicU32::new(NodeIndex::_NONE));
+
+    /// Load the current value of the `AtomicNodeIndex`.
+    pub fn load(&self) -> NodeIndex {
+        let index = NonZeroU32::new(self.0.load(Ordering::Relaxed))
+            .expect("value stored was a valid `NodeIndex`");
+
+        NodeIndex(index)
+    }
+
+    /// Set the value of the `AtomicNodeIndex`.
+    pub fn set(&self, index: NodeIndex) {
+        self.0.store(index.0.get(), Ordering::Relaxed);
+    }
+}
+
+impl Default for AtomicNodeIndex {
+    fn default() -> Self {
+        Self::NONE
     }
 }
 
 impl std::fmt::Debug for AtomicNodeIndex {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        if *self == AtomicNodeIndex::dummy() {
-            f.debug_tuple("AtomicNodeIndex").finish_non_exhaustive()
-        } else {
-            f.debug_tuple("AtomicNodeIndex").field(&self.0).finish()
-        }
+        std::fmt::Debug::fmt(&self.load(), f)
     }
 }
 
@@ -108,3 +128,26 @@ impl Clone for AtomicNodeIndex {
         Self(AtomicU32::from(self.0.load(Ordering::Relaxed)))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{AtomicNodeIndex, NodeIndex};
+
+    #[test]
+    fn test_node_index() {
+        let index = AtomicNodeIndex::NONE;
+
+        assert_eq!(index.load(), NodeIndex::NONE);
+        assert_eq!(format!("{index:?}"), "NodeIndex(None)");
+
+        index.set(NodeIndex::from(1));
+        assert_eq!(index.load(), NodeIndex::from(1));
+        assert_eq!(index.load().as_u32(), Some(1));
+
+        let index = NodeIndex::from(0);
+        assert_eq!(index.as_u32(), Some(0));
+
+        let index = NodeIndex::NONE;
+        assert_eq!(index.as_u32(), None);
+    }
+}

crates/ruff_python_ast/src/nodes.rs

@@ -515,7 +515,7 @@ impl FStringValue {
 
     /// Returns `true` if the node represents an empty f-string literal.
     ///
-    /// Noteh that a [`FStringValue`] node will always have >= 1 [`FStringPart`]s inside it.
+    /// Note that a [`FStringValue`] node will always have >= 1 [`FStringPart`]s inside it.
     /// This method checks whether the value of the concatenated parts is equal to the empty
     /// f-string, not whether the f-string has 0 parts inside it.
     pub fn is_empty_literal(&self) -> bool {
@@ -681,6 +681,22 @@ impl TStringValue {
     pub fn elements(&self) -> impl Iterator<Item = &InterpolatedStringElement> {
         self.iter().flat_map(|tstring| tstring.elements.iter())
     }
+
+    /// Returns `true` if the node represents an empty t-string in the
+    /// sense that `__iter__` returns an empty iterable.
+    ///
+    /// Beware that empty t-strings are still truthy, i.e. `bool(t"") == True`.
+    ///
+    /// Note that a [`TStringValue`] node will always contain at least one
+    /// [`TString`] node. This method checks whether each of the constituent
+    /// t-strings (in an implicitly concatenated t-string) are empty
+    /// in the above sense.
+    pub fn is_empty_iterable(&self) -> bool {
+        match &self.inner {
+            TStringValueInner::Single(tstring) => tstring.is_empty(),
+            TStringValueInner::Concatenated(tstrings) => tstrings.iter().all(TString::is_empty),
+        }
+    }
 }
 
 impl<'a> IntoIterator for &'a TStringValue {
@@ -1182,6 +1198,10 @@ impl TString {
     pub fn quote_style(&self) -> Quote {
         self.flags.quote_style()
     }
+
+    pub fn is_empty(&self) -> bool {
+        self.elements.is_empty()
+    }
 }
 
 impl From<TString> for Expr {
@@ -1582,7 +1602,7 @@ impl StringLiteral {
         Self {
             range,
             value: "".into(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             flags: StringLiteralFlags::empty().with_invalid(),
         }
     }
@@ -1602,7 +1622,7 @@ impl From<StringLiteral> for Expr {
     fn from(payload: StringLiteral) -> Self {
         ExprStringLiteral {
             range: payload.range,
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             value: StringLiteralValue::single(payload),
         }
         .into()
@@ -1981,7 +2001,7 @@ impl BytesLiteral {
         Self {
             range,
             value: Box::new([]),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             flags: BytesLiteralFlags::empty().with_invalid(),
         }
     }
@@ -1991,7 +2011,7 @@ impl From<BytesLiteral> for Expr {
     fn from(payload: BytesLiteral) -> Self {
         ExprBytesLiteral {
             range: payload.range,
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             value: BytesLiteralValue::single(payload),
         }
         .into()
@@ -3525,7 +3545,7 @@ impl Identifier {
     pub fn new(id: impl Into<Name>, range: TextRange) -> Self {
         Self {
             id: id.into(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
             range,
         }
     }

crates/ruff_python_formatter/src/comments/debug.rs

@@ -196,12 +196,12 @@ mod tests {
     fn debug() {
         let continue_statement = StmtContinue {
             range: TextRange::new(TextSize::new(18), TextSize::new(26)),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         };
 
         let break_statement = StmtBreak {
             range: TextRange::new(TextSize::new(55), TextSize::new(60)),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         };
 
         let source = r"# leading comment

crates/ruff_python_formatter/src/comments/node_key.rs

@@ -69,7 +69,7 @@ mod tests {
     fn equality() {
         let continue_statement = StmtContinue {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         };
 
         let ref_a = NodeRefEqualityKey::from_ref(AnyNodeRef::from(&continue_statement));
@@ -83,7 +83,7 @@ mod tests {
     fn inequality() {
         let continue_statement = StmtContinue {
             range: TextRange::default(),
-            node_index: AtomicNodeIndex::dummy(),
+            node_index: AtomicNodeIndex::NONE,
         };
 
         let boxed = Box::new(continue_statement.clone());