Handle empty NamedTuple and TypedDict conversions (#3251)

crates/ruff/resources/test/fixtures/pyupgrade/UP013.py

@@ -35,3 +35,9 @@ MyType = TypedDict("MyType", {"in": int, "x-y": int})
 # unpacking (OK)
 c = {"c": float}
 MyType = TypedDict("MyType", {"a": int, "b": str, **c})
+
+# Empty dict literal
+MyType = TypedDict("MyType", {})
+
+# Empty dict call
+MyType = TypedDict("MyType", dict())

crates/ruff/resources/test/fixtures/pyupgrade/UP014.py

@@ -23,3 +23,9 @@ MyType = NamedTuple(
 
 # invalid identifiers (OK)
 MyType = NamedTuple("MyType", [("x-y", int), ("b", tuple[str, ...])])
+
+# no fields
+MyType = typing.NamedTuple("MyType")
+
+# empty fields
+MyType = typing.NamedTuple("MyType", [])

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

@@ -103,11 +103,14 @@ fn match_defaults(keywords: &[Keyword]) -> Result<&[Expr]> {
 /// Create a list of property assignments from the `NamedTuple` arguments.
 fn create_properties_from_args(args: &[Expr], defaults: &[Expr]) -> Result<Vec<Stmt>> {
     let Some(fields) = args.get(1) else {
-        return Ok(vec![]);
+        return Ok(vec![create_stmt(StmtKind::Pass)]);
     };
     let ExprKind::List { elts, .. } = &fields.node else {
         bail!("Expected argument to be `ExprKind::List`");
     };
+    if elts.is_empty() {
+        return Ok(vec![create_stmt(StmtKind::Pass)]);
+    }
     let padded_defaults = if elts.len() >= defaults.len() {
         std::iter::repeat(None)
             .take(elts.len() - defaults.len())

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

@@ -78,11 +78,6 @@ fn create_property_assignment_stmt(property: &str, annotation: &ExprKind) -> Stm
     })
 }
 
-/// Generate a `StmtKind::Pass` statement.
-fn create_pass_stmt() -> Stmt {
-    create_stmt(StmtKind::Pass)
-}
-
 /// Generate a `StmtKind:ClassDef` statement based on the provided body,
 /// keywords and base class.
 fn create_class_def_stmt(
@@ -105,6 +100,10 @@ fn create_class_def_stmt(
 }
 
 fn properties_from_dict_literal(keys: &[Option<Expr>], values: &[Expr]) -> Result<Vec<Stmt>> {
+    if keys.is_empty() {
+        return Ok(vec![create_stmt(StmtKind::Pass)]);
+    }
+
     keys.iter()
         .zip(values.iter())
         .map(|(key, value)| match key {
@@ -134,11 +133,19 @@ fn properties_from_dict_call(func: &Expr, keywords: &[Keyword]) -> Result<Vec<St
     if id != "dict" {
         bail!("Expected `id` to be `\"dict\"`")
     }
+    if keywords.is_empty() {
+        return Ok(vec![create_stmt(StmtKind::Pass)]);
+    }
+
     properties_from_keywords(keywords)
 }
 
 // Deprecated in Python 3.11, removed in Python 3.13.
 fn properties_from_keywords(keywords: &[Keyword]) -> Result<Vec<Stmt>> {
+    if keywords.is_empty() {
+        return Ok(vec![create_stmt(StmtKind::Pass)]);
+    }
+
     keywords
         .iter()
         .map(|keyword| {
@@ -185,12 +192,12 @@ fn match_properties_and_total<'a>(
             ExprKind::Call { func, keywords, .. } => {
                 Ok((properties_from_dict_call(func, keywords)?, total))
             }
-            _ => Ok((vec![create_pass_stmt()], total)),
+            _ => bail!("Expected `arg` to be `ExprKind::Dict` or `ExprKind::Call`"),
         }
     } else if !keywords.is_empty() {
         Ok((properties_from_keywords(keywords)?, None))
     } else {
-        Ok((vec![create_pass_stmt()], None))
+        Ok((vec![create_stmt(StmtKind::Pass)], None))
     }
 }
 

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP013.py.snap

@@ -192,4 +192,42 @@ expression: diagnostics
       row: 30
       column: 49
   parent: ~
+- kind:
+    ConvertTypedDictFunctionalToClass:
+      name: MyType
+      fixable: true
+  location:
+    row: 40
+    column: 0
+  end_location:
+    row: 40
+    column: 32
+  fix:
+    content: "class MyType(TypedDict):\n    pass"
+    location:
+      row: 40
+      column: 0
+    end_location:
+      row: 40
+      column: 32
+  parent: ~
+- kind:
+    ConvertTypedDictFunctionalToClass:
+      name: MyType
+      fixable: true
+  location:
+    row: 43
+    column: 0
+  end_location:
+    row: 43
+    column: 36
+  fix:
+    content: "class MyType(TypedDict):\n    pass"
+    location:
+      row: 43
+      column: 0
+    end_location:
+      row: 43
+      column: 36
+  parent: ~
 

crates/ruff/src/rules/pyupgrade/snapshots/ruff__rules__pyupgrade__tests__UP014.py.snap

@@ -59,4 +59,42 @@ expression: diagnostics
       row: 15
       column: 62
   parent: ~
+- kind:
+    ConvertNamedTupleFunctionalToClass:
+      name: MyType
+      fixable: true
+  location:
+    row: 28
+    column: 0
+  end_location:
+    row: 28
+    column: 36
+  fix:
+    content: "class MyType(typing.NamedTuple):\n    pass"
+    location:
+      row: 28
+      column: 0
+    end_location:
+      row: 28
+      column: 36
+  parent: ~
+- kind:
+    ConvertNamedTupleFunctionalToClass:
+      name: MyType
+      fixable: true
+  location:
+    row: 31
+    column: 0
+  end_location:
+    row: 31
+    column: 40
+  fix:
+    content: "class MyType(typing.NamedTuple):\n    pass"
+    location:
+      row: 31
+      column: 0
+    end_location:
+      row: 31
+      column: 40
+  parent: ~