diff --git a/crates/ruff/src/ast/context.rs b/crates/ruff/src/ast/context.rs
index 9c08a1b17a..108360b88b 100644
--- a/crates/ruff/src/ast/context.rs
+++ b/crates/ruff/src/ast/context.rs
@@ -5,12 +5,12 @@ use rustc_hash::FxHashMap;
 use rustpython_parser::ast::{Expr, Stmt};
 use smallvec::smallvec;
 
+use ruff_python_stdlib::path::is_python_stub_file;
 use ruff_python_stdlib::typing::TYPING_EXTENSIONS;
 
 use crate::ast::helpers::{collect_call_path, from_relative_import, Exceptions};
 use crate::ast::types::{Binding, BindingKind, CallPath, ExecutionContext, RefEquality, Scope};
 use crate::ast::visibility::{module_visibility, Modifier, VisibleScope};
-use crate::resolver::is_interface_definition_path;
 
 #[allow(clippy::struct_excessive_bools)]
 pub struct Context<'a> {
@@ -82,7 +82,7 @@ impl<'a> Context<'a> {
             in_type_checking_block: false,
             seen_import_boundary: false,
             futures_allowed: true,
-            annotations_future_enabled: is_interface_definition_path(path),
+            annotations_future_enabled: is_python_stub_file(path),
             handled_exceptions: Vec::default(),
         }
     }
diff --git a/crates/ruff/src/checkers/ast/mod.rs b/crates/ruff/src/checkers/ast/mod.rs
index 7cc70af22f..bf8da6f22d 100644
--- a/crates/ruff/src/checkers/ast/mod.rs
+++ b/crates/ruff/src/checkers/ast/mod.rs
@@ -14,6 +14,7 @@ use rustpython_parser::ast::{
 };
 
 use ruff_python_stdlib::builtins::{BUILTINS, MAGIC_GLOBALS};
+use ruff_python_stdlib::path::is_python_stub_file;
 
 use crate::ast::context::Context;
 use crate::ast::helpers::{binding_range, extract_handled_exceptions, to_module_path, Exceptions};
@@ -31,7 +32,6 @@ use crate::docstrings::definition::{
     transition_scope, Definition, DefinitionKind, Docstring, Documentable,
 };
 use crate::registry::{Diagnostic, Rule};
-use crate::resolver::is_interface_definition_path;
 use crate::rules::{
     flake8_2020, flake8_annotations, flake8_bandit, flake8_blind_except, flake8_boolean_trap,
     flake8_bugbear, flake8_builtins, flake8_comprehensions, flake8_datetimez, flake8_debugger,
@@ -58,7 +58,7 @@ pub struct Checker<'a> {
     pub path: &'a Path,
     module_path: Option<Vec<String>>,
     package: Option<&'a Path>,
-    is_interface_definition: bool,
+    is_stub: bool,
     autofix: flags::Autofix,
     noqa: flags::Noqa,
     pub settings: &'a Settings,
@@ -97,7 +97,7 @@ impl<'a> Checker<'a> {
             path,
             package,
             module_path: module_path.clone(),
-            is_interface_definition: is_interface_definition_path(path),
+            is_stub: is_python_stub_file(path),
             locator,
             stylist: style,
             indexer,
@@ -378,7 +378,7 @@ where
                     }
                 }
 
-                if self.is_interface_definition {
+                if self.is_stub {
                     if self.settings.rules.enabled(&Rule::PassStatementStubBody) {
                         flake8_pyi::rules::pass_statement_stub_body(self, body);
                     }
@@ -756,7 +756,7 @@ where
                     flake8_bugbear::rules::useless_expression(self, body);
                 }
 
-                if !self.is_interface_definition {
+                if !self.is_stub {
                     if self
                         .settings
                         .rules
@@ -771,7 +771,7 @@ where
                         );
                     }
                 }
-                if self.is_interface_definition {
+                if self.is_stub {
                     if self.settings.rules.enabled(&Rule::PassStatementStubBody) {
                         flake8_pyi::rules::pass_statement_stub_body(self, body);
                     }
@@ -1805,7 +1805,7 @@ where
                     }
                 }
 
-                if self.is_interface_definition {
+                if self.is_stub {
                     if self.settings.rules.enabled(&Rule::PrefixTypeParams) {
                         flake8_pyi::rules::prefix_type_params(self, value, targets);
                     }
@@ -3301,7 +3301,7 @@ where
                     flake8_simplify::rules::yoda_conditions(self, expr, left, ops, comparators);
                 }
 
-                if self.is_interface_definition {
+                if self.is_stub {
                     if self
                         .settings
                         .rules
@@ -3886,7 +3886,7 @@ where
             flake8_bugbear::rules::function_call_argument_default(self, arguments);
         }
 
-        if self.is_interface_definition {
+        if self.is_stub {
             if self
                 .settings
                 .rules
@@ -3895,7 +3895,7 @@ where
                 flake8_pyi::rules::typed_argument_simple_defaults(self, arguments);
             }
         }
-        if self.is_interface_definition {
+        if self.is_stub {
             if self.settings.rules.enabled(&Rule::ArgumentSimpleDefaults) {
                 flake8_pyi::rules::argument_simple_defaults(self, arguments);
             }
@@ -4710,7 +4710,7 @@ impl<'a> Checker<'a> {
     }
 
     fn check_dead_scopes(&mut self) {
-        let enforce_typing_imports = !self.is_interface_definition
+        let enforce_typing_imports = !self.is_stub
             && (self
                 .settings
                 .rules
@@ -5241,7 +5241,7 @@ impl<'a> Checker<'a> {
                 }
                 overloaded_name = flake8_annotations::helpers::overloaded_name(self, &definition);
             }
-            if self.is_interface_definition {
+            if self.is_stub {
                 if self.settings.rules.enabled(&Rule::DocstringInStub) {
                     flake8_pyi::rules::docstring_in_stubs(self, definition.docstring);
                 }
diff --git a/crates/ruff/src/checkers/tokens.rs b/crates/ruff/src/checkers/tokens.rs
index a8f8e0c2d3..bc5d3c2576 100644
--- a/crates/ruff/src/checkers/tokens.rs
+++ b/crates/ruff/src/checkers/tokens.rs
@@ -18,7 +18,7 @@ pub fn check_tokens(
     tokens: &[LexResult],
     settings: &Settings,
     autofix: flags::Autofix,
-    is_interface_definition: bool,
+    is_stub: bool,
 ) -> Vec<Diagnostic> {
     let mut diagnostics: Vec<Diagnostic> = vec![];
 
@@ -164,7 +164,7 @@ pub fn check_tokens(
     }
 
     // PYI033
-    if enforce_type_comment_in_stub && is_interface_definition {
+    if enforce_type_comment_in_stub && is_stub {
         diagnostics.extend(flake8_pyi::rules::type_comment_in_stub(tokens));
     }
 
diff --git a/crates/ruff/src/linter.rs b/crates/ruff/src/linter.rs
index 94b62c61e8..3221c4f83f 100644
--- a/crates/ruff/src/linter.rs
+++ b/crates/ruff/src/linter.rs
@@ -4,6 +4,7 @@ use std::path::Path;
 use anyhow::{anyhow, Result};
 use colored::Colorize;
 use log::error;
+use ruff_python_stdlib::path::is_python_stub_file;
 use rustc_hash::FxHashMap;
 use rustpython_parser::lexer::LexResult;
 use rustpython_parser::ParseError;
@@ -21,7 +22,6 @@ use crate::doc_lines::{doc_lines_from_ast, doc_lines_from_tokens};
 use crate::message::{Message, Source};
 use crate::noqa::{add_noqa, rule_is_ignored};
 use crate::registry::{Diagnostic, Rule};
-use crate::resolver::is_interface_definition_path;
 use crate::rules::pycodestyle;
 use crate::settings::{flags, Settings};
 use crate::source_code::{Indexer, Locator, Stylist};
@@ -84,14 +84,8 @@ pub fn check_path(
         .iter_enabled()
         .any(|rule_code| rule_code.lint_source().is_tokens())
     {
-        let is_interface_definition = is_interface_definition_path(path);
-        diagnostics.extend(check_tokens(
-            locator,
-            &tokens,
-            settings,
-            autofix,
-            is_interface_definition,
-        ));
+        let is_stub = is_python_stub_file(path);
+        diagnostics.extend(check_tokens(locator, &tokens, settings, autofix, is_stub));
     }
 
     // Run the filesystem-based rules.
diff --git a/crates/ruff/src/resolver.rs b/crates/ruff/src/resolver.rs
index 9206e36c51..421aa309c2 100644
--- a/crates/ruff/src/resolver.rs
+++ b/crates/ruff/src/resolver.rs
@@ -10,6 +10,7 @@ use ignore::{DirEntry, WalkBuilder, WalkState};
 use itertools::Itertools;
 use log::debug;
 use path_absolutize::path_dedot;
+use ruff_python_stdlib::path::is_python_file;
 use rustc_hash::FxHashSet;
 
 use crate::fs;
@@ -191,20 +192,9 @@ fn match_exclusion(file_path: &str, file_basename: &str, exclusion: &globset::Gl
     exclusion.is_match(file_path) || exclusion.is_match(file_basename)
 }
 
-/// Return `true` if the [`Path`] appears to be that of a Python file.
-fn is_python_path(path: &Path) -> bool {
-    path.extension()
-        .map_or(false, |ext| ext == "py" || ext == "pyi")
-}
-
-/// Return `true` if the [`Path`] appears to be that of a Python interface definition file (`.pyi`).
-pub fn is_interface_definition_path(path: &Path) -> bool {
-    path.extension().map_or(false, |ext| ext == "pyi")
-}
-
 /// Return `true` if the [`DirEntry`] appears to be that of a Python file.
 pub fn is_python_entry(entry: &DirEntry) -> bool {
-    is_python_path(entry.path())
+    is_python_file(entry.path())
         && !entry
             .file_type()
             .map_or(false, |file_type| file_type.is_dir())
@@ -430,28 +420,13 @@ mod tests {
 
     use crate::fs;
     use crate::resolver::{
-        is_file_excluded, is_python_path, match_exclusion, resolve_settings_with_processor,
-        NoOpProcessor, PyprojectDiscovery, Relativity, Resolver,
+        is_file_excluded, match_exclusion, resolve_settings_with_processor, NoOpProcessor,
+        PyprojectDiscovery, Relativity, Resolver,
     };
     use crate::settings::pyproject::find_settings_toml;
     use crate::settings::types::FilePattern;
     use crate::test::test_resource_path;
 
-    #[test]
-    fn inclusions() {
-        let path = Path::new("foo/bar/baz.py").absolutize().unwrap();
-        assert!(is_python_path(&path));
-
-        let path = Path::new("foo/bar/baz.pyi").absolutize().unwrap();
-        assert!(is_python_path(&path));
-
-        let path = Path::new("foo/bar/baz.js").absolutize().unwrap();
-        assert!(!is_python_path(&path));
-
-        let path = Path::new("foo/bar/baz").absolutize().unwrap();
-        assert!(!is_python_path(&path));
-    }
-
     fn make_exclusion(file_pattern: FilePattern) -> GlobSet {
         let mut builder = globset::GlobSetBuilder::new();
         file_pattern.add_to(&mut builder).unwrap();
diff --git a/crates/ruff/src/rules/isort/track.rs b/crates/ruff/src/rules/isort/track.rs
index 25d3255b6a..143a75a7a2 100644
--- a/crates/ruff/src/rules/isort/track.rs
+++ b/crates/ruff/src/rules/isort/track.rs
@@ -1,5 +1,6 @@
 use std::path::Path;
 
+use ruff_python_stdlib::path::is_python_stub_file;
 use rustpython_parser::ast::{
     Alias, Arg, Arguments, Boolop, Cmpop, Comprehension, Constant, Excepthandler,
     ExcepthandlerKind, Expr, ExprContext, Keyword, MatchCase, Operator, Pattern, Stmt, StmtKind,
@@ -9,7 +10,6 @@ use rustpython_parser::ast::{
 use super::helpers;
 use crate::ast::visitor::Visitor;
 use crate::directives::IsortDirectives;
-use crate::resolver::is_interface_definition_path;
 use crate::source_code::Locator;
 
 #[derive(Debug)]
@@ -29,7 +29,7 @@ pub struct Block<'a> {
 pub struct ImportTracker<'a> {
     locator: &'a Locator<'a>,
     directives: &'a IsortDirectives,
-    pyi: bool,
+    is_stub: bool,
     blocks: Vec<Block<'a>>,
     split_index: usize,
     nested: bool,
@@ -40,7 +40,7 @@ impl<'a> ImportTracker<'a> {
         Self {
             locator,
             directives,
-            pyi: is_interface_definition_path(path),
+            is_stub: is_python_stub_file(path),
             blocks: vec![Block::default()],
             split_index: 0,
             nested: false,
@@ -65,7 +65,7 @@ impl<'a> ImportTracker<'a> {
             return None;
         }
 
-        Some(if self.pyi {
+        Some(if self.is_stub {
             // Black treats interface files differently, limiting to one newline
             // (`Trailing::Sibling`).
             Trailer::Sibling
diff --git a/crates/ruff_python_stdlib/src/lib.rs b/crates/ruff_python_stdlib/src/lib.rs
index 26696bd2a2..daa9776582 100644
--- a/crates/ruff_python_stdlib/src/lib.rs
+++ b/crates/ruff_python_stdlib/src/lib.rs
@@ -3,6 +3,7 @@ pub mod bytes;
 pub mod future;
 pub mod identifiers;
 pub mod keyword;
+pub mod path;
 pub mod str;
 pub mod sys;
 pub mod typing;
diff --git a/crates/ruff_python_stdlib/src/path.rs b/crates/ruff_python_stdlib/src/path.rs
new file mode 100644
index 0000000000..2c48f44c2d
--- /dev/null
+++ b/crates/ruff_python_stdlib/src/path.rs
@@ -0,0 +1,34 @@
+use std::path::Path;
+
+/// Return `true` if the [`Path`] appears to be that of a Python file.
+pub fn is_python_file(path: &Path) -> bool {
+    path.extension()
+        .map_or(false, |ext| ext == "py" || ext == "pyi")
+}
+
+/// Return `true` if the [`Path`] appears to be that of a Python interface definition file (`.pyi`).
+pub fn is_python_stub_file(path: &Path) -> bool {
+    path.extension().map_or(false, |ext| ext == "pyi")
+}
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use crate::path::is_python_file;
+
+    #[test]
+    fn inclusions() {
+        let path = Path::new("foo/bar/baz.py");
+        assert!(is_python_file(path));
+
+        let path = Path::new("foo/bar/baz.pyi");
+        assert!(is_python_file(path));
+
+        let path = Path::new("foo/bar/baz.js");
+        assert!(!is_python_file(path));
+
+        let path = Path::new("foo/bar/baz");
+        assert!(!is_python_file(path));
+    }
+}