[3.13] gh-131936: Strengthen check in _suggestions._generate_suggestions (GH-131945) (#131949)

miss-islington · ZeroIntensity · web-flow · commit d52371c8cdaf · 2025-03-31T17:54:20.000Z
gh-131936: Strengthen check in `_suggestions._generate_suggestions` (GH-131945) (cherry picked from commit 511d344) Co-authored-by: Peter Bierma <zintensitydev@gmail.com>
diff --git a/Lib/test/test_traceback.py b/Lib/test/test_traceback.py
@@ -4615,7 +4615,31 @@ def test_levenshtein_distance_short_circuit(self):
     @cpython_only
     def test_suggestions_extension(self):
         # Check that the C extension is available
-        import _suggestions  # noqa: F401
+        import _suggestions
+
+        self.assertEqual(
+            _suggestions._generate_suggestions(
+                ["hello", "world"],
+                "hell"
+            ),
+            "hello"
+        )
+        self.assertEqual(
+            _suggestions._generate_suggestions(
+                ["hovercraft"],
+                "eels"
+            ),
+            None
+        )
+
+        # gh-131936: _generate_suggestions() doesn't accept list subclasses
+        class MyList(list):
+            pass
+
+        with self.assertRaises(TypeError):
+            _suggestions._generate_suggestions(MyList(), "")
+
+
 
 
 class TestColorizedTraceback(unittest.TestCase):
diff --git a/Modules/_suggestions.c b/Modules/_suggestions.c
@@ -21,7 +21,7 @@ _suggestions__generate_suggestions_impl(PyObject *module,
 /*[clinic end generated code: output=79be7b653ae5e7ca input=ba2a8dddc654e33a]*/
 {
    // Check if dir is a list
-    if (!PyList_Check(candidates)) {
+    if (!PyList_CheckExact(candidates)) {
         PyErr_SetString(PyExc_TypeError, "candidates must be a list");
         return NULL;
     }

Original file line number	Diff line number	Diff line change
`@@ -21,7 +21,7 @@ _suggestions__generate_suggestions_impl(PyObject *module,`
`21`	`21`	`/[clinic end generated code: output=79be7b653ae5e7ca input=ba2a8dddc654e33a]/`
`22`	`22`	`{`
`23`	`23`	`// Check if dir is a list`
`24`		`- if (!PyList_Check(candidates)) {`
	`24`	`+ if (!PyList_CheckExact(candidates)) {`
`25`	`25`	`PyErr_SetString(PyExc_TypeError, "candidates must be a list");`
`26`	`26`	`return NULL;`
`27`	`27`	`}`