future annotations

Author: MarcoGorelli

.pre-commit-config.yaml

@@ -156,6 +156,19 @@ repos:
             |(pd|pandas)\.api\.types\.
         files: ^pandas/tests/
         types_or: [python, cython, rst]
+    -   id: future-annotations
+        name: Use from __future__ import annotations in source code
+        language: pygrep
+        entry: from __future__ import annotations
+        files: ^pandas/
+        exclude: |
+            (?x)
+            __init__
+            |^pandas/tests/
+            |pandas/io/formats/_color_data\.py
+            |pandas/io/sas/sas_constants\.py
+        args: [--negate]
+        types: [python]
     -   id: pip-to-conda
         name: Generate pip dependency from conda
         description: This hook checks if the conda environment.yml and requirements-dev.txt are equal

pandas/_config/config.py

@@ -48,6 +48,8 @@
 
 """
 
+from __future__ import annotations
+
 from collections import namedtuple
 from contextlib import (
     ContextDecorator,

pandas/_config/dates.py

@@ -1,6 +1,8 @@
 """
 config for datetime formatting
 """
+from __future__ import annotations
+
 from pandas._config import config as cf
 
 pc_date_dayfirst_doc = """

pandas/_config/display.py

@@ -2,6 +2,8 @@
 Unopinionated display configuration.
 """
 
+from __future__ import annotations
+
 import locale
 import sys
 from typing import Optional

pandas/_config/localization.py

@@ -3,6 +3,8 @@
 
 Name `localization` is chosen to avoid overlap with builtin `locale` module.
 """
+from __future__ import annotations
+
 from contextlib import contextmanager
 import locale
 import re

pandas/_testing/_io.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import bz2
 from functools import wraps
 import gzip

pandas/_testing/_random.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import string
 
 import numpy as np

pandas/_testing/_warnings.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from contextlib import contextmanager
 import re
 from typing import (

pandas/_testing/asserters.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from typing import (
     Union,
     cast,

pandas/_testing/compat.py

@@ -2,6 +2,8 @@
 Helpers for sharing tests between DataFrame/Series
 """
 
+from __future__ import annotations
+
 from pandas import DataFrame