`from __future__ import annotations` now implies 3.7+ (#2690)

[etc/vim.git] / src / black / mode.py

diff --git a/src/black/mode.py b/src/black/mode.py
index e2417531240b7c38ae0a61d782a84f9cdf9ee7fd..a2b7d9e9e2d8708e49e2733aa4811b53c7fc547d 100644 (file)
--- a/src/black/mode.py
+++ b/src/black/mode.py
@@ -4,11 +4,18 @@ Mostly around Python language feature support per version and Black configuratio
 chosen by the user.
 """
 
+import sys
+
 from dataclasses import dataclass, field
 from enum import Enum
 from operator import attrgetter
 from typing import Dict, Set
 
+if sys.version_info < (3, 8):
+    from typing_extensions import Final
+else:
+    from typing import Final
+
 from black.const import DEFAULT_LINE_LENGTH
 
 
@@ -44,6 +51,9 @@ class Feature(Enum):
     PATTERN_MATCHING = 11
     FORCE_OPTIONAL_PARENTHESES = 50
 
+    # __future__ flags
+    FUTURE_ANNOTATIONS = 51
+
     # temporary for Python 2 deprecation
     PRINT_STMT = 200
     EXEC_STMT = 201
@@ -55,6 +65,11 @@ class Feature(Enum):
     BACKQUOTE_REPR = 207
 
 
+FUTURE_FLAG_TO_FEATURE: Final = {
+    "annotations": Feature.FUTURE_ANNOTATIONS,
+}
+
+
 VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
     TargetVersion.PY27: {
         Feature.ASYNC_IDENTIFIERS,
@@ -89,6 +104,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
     },
     TargetVersion.PY38: {
         Feature.UNICODE_LITERALS,
@@ -97,6 +113,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
         Feature.ASSIGNMENT_EXPRESSIONS,
         Feature.POS_ONLY_ARGUMENTS,
     },
@@ -107,6 +124,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
         Feature.ASSIGNMENT_EXPRESSIONS,
         Feature.RELAXED_DECORATORS,
         Feature.POS_ONLY_ARGUMENTS,
@@ -118,6 +136,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
         Feature.ASSIGNMENT_EXPRESSIONS,
         Feature.RELAXED_DECORATORS,
         Feature.POS_ONLY_ARGUMENTS,