fix(ERA001): detect commented out case statements, add more one-lin…

…e support (#10055)

## Summary

Closes #10031 

- Detect commented out `case` statements. Playground repro:
https://play.ruff.rs/5a305aa9-6e5c-4fa4-999a-8fc427ab9a23
- Add more support for one-line commented out code.

## Test Plan

Unit tested and tested with
```sh
cargo run -p ruff -- check crates/ruff_linter/resources/test/fixtures/eradicate/ERA001.py --no-cache --preview --select ERA001
```

TODO:
- [x] `cargo insta test`

crates/ruff_linter/resources/test/fixtures/eradicate/ERA001.py

@@ -28,3 +28,5 @@ class A():
 }
 
 #import os  # noqa
+
+# case 1:

crates/ruff_linter/src/rules/eradicate/detection.rs

@@ -26,7 +26,7 @@ static HASH_NUMBER: Lazy<Regex> = Lazy::new(|| Regex::new(r"#\d").unwrap());
 static POSITIVE_CASES: Lazy<RegexSet> = Lazy::new(|| {
     RegexSet::new([
         // Keywords
-        r"^(?:elif\s+.*\s*:|else\s*:|try\s*:|finally\s*:|except\s+.*\s*:)$",
+        r"^(?:elif\s+.*\s*:|else\s*:|try\s*:|finally\s*:|except\s+.*\s*|case\s+.*\s*:)$",
         // Partial dictionary
         r#"^['"]\w+['"]\s*:.+[,{]\s*(#.*)?$"#,
         // Multiline assignment
@@ -155,11 +155,14 @@ mod tests {
         assert!(comment_contains_code("#elif True:", &[]));
         assert!(comment_contains_code("#x = foo(", &[]));
         assert!(comment_contains_code("#except Exception:", &[]));
+        assert!(comment_contains_code("# case 1:", &[]));
+        assert!(comment_contains_code("#case 1:", &[]));
 
         assert!(!comment_contains_code("# this is = to that :(", &[]));
         assert!(!comment_contains_code("#else", &[]));
         assert!(!comment_contains_code("#or else:", &[]));
         assert!(!comment_contains_code("#else True:", &[]));
+        assert!(!comment_contains_code("# in that case:", &[]));
 
         // Unpacking assignments
         assert!(comment_contains_code(

crates/ruff_linter/src/rules/eradicate/rules/commented_out_code.rs

@@ -47,7 +47,8 @@ fn is_standalone_comment(line: &str) -> bool {
     for char in line.chars() {
         if char == '#' {
             return true;
-        } else if !char.is_whitespace() {
+        }
+        if !char.is_whitespace() {
             return false;
         }
     }

crates/ruff_linter/src/rules/eradicate/snapshots/ruff_linter__rules__eradicate__tests__ERA001_ERA001.py.snap

@@ -148,4 +148,17 @@ ERA001.py:27:5: ERA001 Found commented-out code
 29 28 | 
 30 29 | #import os  # noqa
 
+ERA001.py:32:1: ERA001 Found commented-out code
+   |
+30 | #import os  # noqa
+31 | 
+32 | # case 1:
+   | ^^^^^^^^^ ERA001
+   |
+   = help: Remove commented-out code
 
+ℹ Display-only fix
+29 29 | 
+30 30 | #import os  # noqa
+31 31 | 
+32    |-# case 1: