Restore expectation that mkpath returns a list of the items it created.

Closes pypa#305

Author: jaraco

distutils/dir_util.py

@@ -58,7 +58,7 @@ def mkpath(name: pathlib.Path, mode=0o777, verbose=True, dry_run=False):
         log.info("creating %s", name)
 
     ancestry = itertools.chain((name,), name.parents)
-    missing = (path for path in ancestry if not path.is_dir())
+    missing = list(path for path in ancestry if not path.is_dir())
 
     try:
         dry_run or name.mkdir(mode=mode, parents=True, exist_ok=True)

distutils/tests/test_dir_util.py

@@ -52,6 +52,17 @@ def test_mkpath_with_custom_mode(self):
         mkpath(self.target2, 0o555)
         assert stat.S_IMODE(os.stat(self.target2).st_mode) == 0o555 & ~umask
 
+    def test_mkpath_returns_as_described(self, tmp_path):
+        """
+        Per the docstring, mkpath should return the list of directories created.
+
+        pypa/distutils#305 revealed that the return value is always the empty
+        string and no one complained. Consider removing this expectation.
+        """
+        target = tmp_path / 'foodir'
+        res = mkpath(target)
+        assert res == [str(target)]
+
     def test_create_tree_verbosity(self, caplog):
         create_tree(self.root_target, ['one', 'two', 'three'], verbose=False)
         assert caplog.messages == []