utils: Change `normalize_paths()` contract

The `normalize_paths()` utility was doing too much — parsing
unstructured configuration path data and dispatching the scrubbed paths
to be normalized.

Towards moving the parsing of unstructured configuration path data
closer towards were configuration occurs, have the utility accept only
structured input for normalizing paths.

1 files changed, 3 insertions, 5 deletions

diff --git a/src/flake8/utils.py b/src/flake8/utils.py
index bb6ba2e..5ed78e1 100644
--- a/src/flake8/utils.py
+++ b/src/flake8/utils.py
@@ -160,8 +160,8 @@ def parse_files_to_codes_mapping(value_):  # noqa: C901
 
 
 def normalize_paths(paths, parent=os.curdir):
-    # type: (Union[Sequence[str], str], str) -> List[str]
-    """Parse a comma-separated list of paths.
+    # type: (Sequence[str], str) -> List[str]
+    """Normalize a list of paths relative to a parent directory.
 
     :returns:
         The normalized paths.
@@ -169,9 +169,7 @@ def normalize_paths(paths, parent=os.curdir):
         [str]
     """
     assert isinstance(paths, list), paths  # nosec (for bandit)
-    return [
-        normalize_path(p, parent) for p in parse_comma_separated_list(paths)
-    ]
+    return [normalize_path(p, parent) for p in paths]
 
 
 def normalize_path(path, parent=os.curdir):