Merge pull request #1 from abravalheri/ast-annotation

Refactor `StaticModule.__getattr__` and fix `ast.AnnAssign` edge case

Author: karlotness

setuptools/config/expand.py

@@ -66,24 +66,23 @@ def __init__(self, name: str, spec: ModuleSpec):
         vars(self).update(locals())
         del self.self
 
+    def _find_assignments(self) -> Iterator[Tuple[ast.AST, ast.AST]]:
+        for statement in self.module.body:
+            if isinstance(statement, ast.Assign):
+                yield from ((target, statement.value) for target in statement.targets)
+            elif isinstance(statement, ast.AnnAssign) and statement.value:
+                yield (statement.target, statement.value)
+
     def __getattr__(self, attr):
         """Attempt to load an attribute "statically", via :func:`ast.literal_eval`."""
         try:
-            for statement in self.module.body:
-                if isinstance(statement, ast.Assign):
-                    targets = statement.targets
-                    value = statement.value
-                elif isinstance(statement, ast.AnnAssign):
-                    targets = [statement.target]
-                    value = statement.value
-                else:
-                    continue
-                for target in targets:
-                    if isinstance(target, ast.Name) and target.id == attr:
-                        return ast.literal_eval(value)
+            return next(
+                ast.literal_eval(value)
+                for target, value in self._find_assignments()
+                if isinstance(target, ast.Name) and target.id == attr
+            )
         except Exception as e:
             raise AttributeError(f"{self.name} has no attribute {attr}") from e
-        raise AttributeError(f"{self.name} has no attribute {attr}")
 
 
 def glob_relative(

setuptools/tests/config/test_expand.py

@@ -85,13 +85,17 @@ def test_read_attr(self, tmp_path, monkeypatch):
         values = expand.read_attr('lib.mod.VALUES', {'lib': 'pkg/sub'}, tmp_path)
         assert values['c'] == (0, 1, 1)
 
-    def test_read_annotated_attr(self, tmp_path):
+    @pytest.mark.parametrize(
+        "example",
+        [
+            "VERSION: str\nVERSION = '0.1.1'\nraise SystemExit(1)\n",
+            "VERSION: str = '0.1.1'\nraise SystemExit(1)\n",
+        ]
+    )
+    def test_read_annotated_attr(self, tmp_path, example):
         files = {
             "pkg/__init__.py": "",
-            "pkg/sub/__init__.py": (
-                "VERSION: str = '0.1.1'\n"
-                "raise SystemExit(1)\n"
-            ),
+            "pkg/sub/__init__.py": example,
         }
         write_files(files, tmp_path)
         # Make sure this attribute can be read statically