fix: normalize all extras, not just the first one (#1024)

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

Author: henryiii

src/packaging/markers.py

@@ -122,20 +122,28 @@ class Environment(TypedDict):
     """
 
 
+def _normalize_extras(
+    result: MarkerList | MarkerAtom | str,
+) -> MarkerList | MarkerAtom | str:
+    if not isinstance(result, tuple):
+        return result
+
+    lhs, op, rhs = result
+    if isinstance(lhs, Variable) and lhs.value == "extra":
+        normalized_extra = canonicalize_name(rhs.value)
+        rhs = Value(normalized_extra)
+    elif isinstance(rhs, Variable) and rhs.value == "extra":
+        normalized_extra = canonicalize_name(lhs.value)
+        lhs = Value(normalized_extra)
+    return lhs, op, rhs
+
+
 def _normalize_extra_values(results: MarkerList) -> MarkerList:
     """
     Normalize extra values.
     """
-    if isinstance(results[0], tuple):
-        lhs, op, rhs = results[0]
-        if isinstance(lhs, Variable) and lhs.value == "extra":
-            normalized_extra = canonicalize_name(rhs.value)
-            rhs = Value(normalized_extra)
-        elif isinstance(rhs, Variable) and rhs.value == "extra":
-            normalized_extra = canonicalize_name(lhs.value)
-            lhs = Value(normalized_extra)
-        results[0] = lhs, op, rhs
-    return results
+
+    return [_normalize_extras(r) for r in results]
 
 
 def _format_marker(

tests/test_requirements.py

@@ -145,6 +145,24 @@ def test_basic_valid_requirement_parsing(
     assert req.marker == (Marker(marker.format(ws="")) if marker else None)
 
 
+@pytest.mark.parametrize(
+    ("input_req", "norm_req"),
+    [
+        (
+            'mariadb>=1.0.1; extra == "mariadb_connector"',
+            'mariadb>=1.0.1; extra == "mariadb-connector"',
+        ),
+        (
+            'mariadb>=1.0.1; python_version >= "3" and extra == "mariadb_connector"',
+            'mariadb>=1.0.1; python_version >= "3" and extra == "mariadb-connector"',
+        ),
+    ],
+)
+def test_normalized_requirements(input_req: str, norm_req: str) -> None:
+    req = Requirement(input_req)
+    assert str(req) == norm_req
+
+
 class TestRequirementParsing:
     @pytest.mark.parametrize(
         "marker",