mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-19 01:05:26 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 4

bpo-38605: Make 'from __future__ import annotations' the default (GH-20434)

Browse source 
The hard part was making all the tests pass; there are some subtle issues here, because apparently the future import wasn't tested very thoroughly in previous Python versions.

For example, `inspect.signature()` returned type objects normally (except for forward references), but strings with the future import. We changed it to try and return type objects by calling `typing.get_type_hints()`, but fall back on returning strings if that function fails (which it may do if there are future references in the annotations that require passing in a specific namespace to resolve).
This commit is contained in:
Batuhan Taskaya 2020-10-06 23:03:02 +03:00 • committed by GitHub
parent bef7d299eb
commit 044a1048ca
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
27 changed files with 403 additions and 299 deletions
Download patch file Download diff file Expand all files Collapse all files

32
Lib/test/dataclass_module_1_str.py
View file

@ -1,32 +0,0 @@
from __future__ import annotations
USING_STRINGS = True
# dataclass_module_1.py and dataclass_module_1_str.py are identical
# except only the latter uses string annotations.
import dataclasses
import typing
T_CV2 = typing.ClassVar[int]
T_CV3 = typing.ClassVar
T_IV2 = dataclasses.InitVar[int]
T_IV3 = dataclasses.InitVar
@dataclasses.dataclass
class CV:
T_CV4 = typing.ClassVar
cv0: typing.ClassVar[int] = 20
cv1: typing.ClassVar = 30
cv2: T_CV2
cv3: T_CV3
not_cv4: T_CV4 # When using string annotations, this field is not recognized as a ClassVar.
@dataclasses.dataclass
class IV:
T_IV4 = dataclasses.InitVar
iv0: dataclasses.InitVar[int]
iv1: dataclasses.InitVar
iv2: T_IV2
iv3: T_IV3
not_iv4: T_IV4 # When using string annotations, this field is not recognized as an InitVar.