Per review

Author: InSyncWithFoo

crates/ruff_linter/resources/test/fixtures/pylint/bad_str_strip_call.py

@@ -80,6 +80,16 @@
 ''.strip(r'\b\x09')
 ''.strip('\\\x5C')
 
+# Errors: Type inference
+b = b''
+b.strip(b'//')
+
+# Errors: Type inference (preview)
+foo: str = ""; bar: bytes = b""
+foo.rstrip("//")
+bar.lstrip(b"//")
+
+
 # OK: Different types
 b"".strip("//")
 "".strip(b"//")
@@ -93,13 +103,8 @@
 "".rstrip()
 
 # OK: Not literals
-foo: str = ""; bar: bytes = b""
 "".strip(foo)
 b"".strip(bar)
 
-# False negative
-foo.rstrip("//")
-bar.lstrip(b"//")
-
 # OK: Not `.[lr]?strip`
 "".mobius_strip("")

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

@@ -82,10 +82,12 @@ impl ValueKind {
                 let binding_id = semantic.only_binding(name)?;
                 let binding = semantic.binding(binding_id);
 
-                match () {
-                    () if typing::is_string(binding, semantic) => Some(Self::String),
-                    () if typing::is_bytes(binding, semantic) => Some(Self::Bytes),
-                    () => None,
+                if typing::is_string(binding, semantic) {
+                    Some(Self::String)
+                } else if typing::is_bytes(binding, semantic) {
+                    Some(Self::Bytes)
+                } else {
+                    None
                 }
             }
             _ => None,
@@ -183,7 +185,7 @@ pub(crate) fn bad_str_strip_call(checker: &Checker, call: &ast::ExprCall) {
         return;
     };
 
-    let value = value.as_ref();
+    let value = &**value;
 
     if checker.settings.preview.is_disabled()
         && !matches!(value, Expr::StringLiteral(_) | Expr::BytesLiteral(_))

crates/ruff_linter/src/rules/pylint/snapshots/ruff_linter__rules__pylint__tests__PLE1310_bad_str_strip_call.py.snap

@@ -179,5 +179,5 @@ bad_str_strip_call.py:81:10: PLE1310 String `strip` call contains duplicate char
 81 | ''.strip('\\\x5C')
    |          ^^^^^^^^ PLE1310
 82 |
-83 | # OK: Different types
+83 | # Errors: Type inference
    |

crates/ruff_linter/src/rules/pylint/snapshots/ruff_linter__rules__pylint__tests__preview__PLE1310_bad_str_strip_call.py.snap

@@ -179,23 +179,32 @@ bad_str_strip_call.py:81:10: PLE1310 String `strip` call contains duplicate char
 81 | ''.strip('\\\x5C')
    |          ^^^^^^^^ PLE1310
 82 |
-83 | # OK: Different types
-   |
-
-bad_str_strip_call.py:101:12: PLE1310 String `rstrip` call contains duplicate characters (did you mean `removesuffix`?)
-    |
-100 | # False negative
-101 | foo.rstrip("//")
-    |            ^^^^ PLE1310
-102 | bar.lstrip(b"//")
-    |
-
-bad_str_strip_call.py:102:12: PLE1310 String `lstrip` call contains duplicate characters (did you mean `removeprefix`?)
-    |
-100 | # False negative
-101 | foo.rstrip("//")
-102 | bar.lstrip(b"//")
-    |            ^^^^^ PLE1310
-103 |
-104 | # OK: Not `.[lr]?strip`
-    |
+83 | # Errors: Type inference
+   |
+
+bad_str_strip_call.py:85:9: PLE1310 String `strip` call contains duplicate characters
+   |
+83 | # Errors: Type inference
+84 | b = b''
+85 | b.strip(b'//')
+   |         ^^^^^ PLE1310
+86 |
+87 | # Errors: Type inference (preview)
+   |
+
+bad_str_strip_call.py:89:12: PLE1310 String `rstrip` call contains duplicate characters (did you mean `removesuffix`?)
+   |
+87 | # Errors: Type inference (preview)
+88 | foo: str = ""; bar: bytes = b""
+89 | foo.rstrip("//")
+   |            ^^^^ PLE1310
+90 | bar.lstrip(b"//")
+   |
+
+bad_str_strip_call.py:90:12: PLE1310 String `lstrip` call contains duplicate characters (did you mean `removeprefix`?)
+   |
+88 | foo: str = ""; bar: bytes = b""
+89 | foo.rstrip("//")
+90 | bar.lstrip(b"//")
+   |            ^^^^^ PLE1310
+   |

crates/ruff_python_semantic/src/analyze/typing.rs

@@ -754,7 +754,7 @@ struct BytesChecker;
 impl BuiltinTypeChecker for BytesChecker {
     const BUILTIN_TYPE_NAME: &'static str = "bytes";
     const TYPING_NAME: Option<&'static str> = None;
-    const EXPR_TYPE: PythonType = PythonType::String;
+    const EXPR_TYPE: PythonType = PythonType::Bytes;
 }
 
 struct TupleChecker;