Remove regex for noqa code splitting (#4569)

crates/ruff/resources/test/fixtures/ruff/noqa.py

@@ -0,0 +1,23 @@
+def f():
+    # These should both be ignored by the `noqa`.
+    I = 1  # noqa: E741, F841
+
+
+def f():
+    # These should both be ignored by the `noqa`.
+    I = 1  # noqa: E741,F841
+
+
+def f():
+    # These should both be ignored by the `noqa`.
+    I = 1  # noqa: E741 F841
+
+
+def f():
+    # These should both be ignored by the `noqa`.
+    I = 1  # noqa: E741 , F841
+
+
+def f():
+    # Only `E741` should be ignored by the `noqa`.
+    I = 1  # noqa: E741.F841

crates/ruff/src/noqa.rs

@@ -24,7 +24,6 @@ static NOQA_LINE_REGEX: Lazy<Regex> = Lazy::new(|| {
     )
     .unwrap()
 });
-static SPLIT_COMMA_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"[,\s]").unwrap());
 
 #[derive(Debug)]
 pub(crate) enum Directive<'a> {
@@ -46,12 +45,12 @@ pub(crate) fn extract_noqa_directive<'a>(range: TextRange, locator: &'a Locator)
             caps.name("trailing_spaces"),
         ) {
             (Some(leading_spaces), Some(noqa), Some(codes), Some(trailing_spaces)) => {
-                let codes: Vec<&str> = SPLIT_COMMA_REGEX
-                    .split(codes.as_str().trim())
+                let codes = codes
+                    .as_str()
+                    .split(|c: char| c.is_whitespace() || c == ',')
                     .map(str::trim)
                     .filter(|code| !code.is_empty())
-                    .collect();
-
+                    .collect_vec();
                 let start = range.start() + TextSize::try_from(noqa.start()).unwrap();
                 if codes.is_empty() {
                     #[allow(deprecated)]
@@ -105,11 +104,11 @@ fn parse_file_exemption(line: &str) -> ParsedExemption {
         if remainder.is_empty() {
             return ParsedExemption::All;
         } else if let Some(codes) = remainder.strip_prefix(':') {
-            let codes: Vec<&str> = SPLIT_COMMA_REGEX
-                .split(codes.trim())
+            let codes = codes
+                .split(|c: char| c.is_whitespace() || c == ',')
                 .map(str::trim)
                 .filter(|code| !code.is_empty())
-                .collect();
+                .collect_vec();
             if codes.is_empty() {
                 warn!("Expected rule codes on `noqa` directive: \"{line}\"");
             }

crates/ruff/src/rules/ruff/mod.rs

@@ -46,6 +46,16 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn noqa() -> Result<()> {
+        let diagnostics = test_path(
+            Path::new("ruff/noqa.py"),
+            &settings::Settings::for_rules(vec![Rule::UnusedVariable, Rule::AmbiguousVariableName]),
+        )?;
+        assert_messages!(diagnostics);
+        Ok(())
+    }
+
     #[test]
     fn ruf100_0() -> Result<()> {
         let diagnostics = test_path(

crates/ruff/src/rules/ruff/snapshots/ruff__rules__ruff__tests__noqa.snap

@@ -0,0 +1,20 @@
+---
+source: crates/ruff/src/rules/ruff/mod.rs
+---
+noqa.py:23:5: F841 [*] Local variable `I` is assigned to but never used
+   |
+23 | def f():
+24 |     # Only `E741` should be ignored by the `noqa`.
+25 |     I = 1  # noqa: E741.F841
+   |     ^ F841
+   |
+   = help: Remove assignment to unused variable `I`
+
+ℹ Suggested fix
+20 20 | 
+21 21 | def f():
+22 22 |     # Only `E741` should be ignored by the `noqa`.
+23    |-    I = 1  # noqa: E741.F841
+   23 |+    pass  # noqa: E741.F841
+
+