first/last approach

astral-sh · Feb 6, 2025 · e2768ce · e2768ce
1 parent 6e628b1
commit e2768ce
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Showing 2 changed files with 27 additions and 28 deletions.
diff --git a/crates/ruff/tests/lint.rs b/crates/ruff/tests/lint.rs
@@ -2300,13 +2300,11 @@ fn a005_module_shadowing_strict() -> Result<()> {
         ----- stdout -----
         abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         collections/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        collections/abc/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        collections/foobar/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
+        collections/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         foobar/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         foobar/collections/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        foobar/collections/abc/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        foobar/collections/foobar/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        Found 8 errors.
+        foobar/collections/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
+        Found 6 errors.
 
         ----- stderr -----
         ");
@@ -2342,13 +2340,11 @@ fn a005_module_shadowing_strict() -> Result<()> {
         ----- stdout -----
         abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         collections/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        collections/abc/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        collections/foobar/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
+        collections/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         foobar/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
         foobar/collections/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        foobar/collections/abc/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        foobar/collections/foobar/__init__.py:1:1: A005 Module `collections` shadows a Python standard-library module
-        Found 8 errors.
+        foobar/collections/abc/__init__.py:1:1: A005 Module `abc` shadows a Python standard-library module
+        Found 6 errors.
 
         ----- stderr -----
         ");

diff --git a/crates/ruff_linter/src/rules/flake8_builtins/rules/stdlib_module_shadowing.rs b/crates/ruff_linter/src/rules/flake8_builtins/rules/stdlib_module_shadowing.rs
@@ -79,28 +79,31 @@ pub(crate) fn stdlib_module_shadowing(
         Cow::from(path.with_extension(""))
     };
 
-    // convert a filesystem path like `foobar/collections/abc` to a sequence of modules like
-    // `["foobar", "collections", "abc"]`, stripping anything that's not a normal component
-    for component in path
+    // convert a filesystem path like `foobar/collections/abc` to a reversed sequence of modules
+    // like `["foobar", "collections", "abc"]`, stripping anything that's not a normal component
+    let mut components = path
         .components()
         .filter(|c| matches!(c, Component::Normal(_)))
-        .map(|c| c.as_os_str().to_string_lossy())
-    {
-        if !is_allowed_module(settings, &component) {
-            return Some(Diagnostic::new(
-                StdlibModuleShadowing {
-                    name: component.to_string(),
-                },
-                TextRange::default(),
-            ));
-        }
-        // in non-strict mode we only consider the first component
-        if !settings.flake8_builtins.builtins_strict_checking {
-            break;
-        }
+        .map(|c| c.as_os_str().to_string_lossy());
+
+    // in strict mode, check the last path component, matching the upstream rule. in non-strict
+    // mode, only compare the first component (the root package)
+    let module_name = if settings.flake8_builtins.builtins_strict_checking {
+        components.last()?
+    } else {
+        components.next()?
+    };
+
+    if is_allowed_module(settings, &module_name) {
+        return None;
     }
 
-    None
+    Some(Diagnostic::new(
+        StdlibModuleShadowing {
+            name: module_name.to_string(),
+        },
+        TextRange::default(),
+    ))
 }
 
 /// Return the longest prefix of `path` between `settings.src` and `settings.project_root`.