mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-04 08:59:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 11

gh-98886: Fix issues with dataclass fields with special underscore names (#102032)

Browse source 
This commit prefixes `__dataclass` to several things in the locals dict:
- Names like `_dflt_` (which cause trouble, see first test)
- Names like `_type_` (not known to be able to cause trouble)
- `_return_type` (not known to able to cause trouble)
- `_HAS_DEFAULT_FACTORY` (which causes trouble, see second test)

In addition, this removes `MISSING` from the locals dict. As far as I can tell, this wasn't needed even in the initial implementation of dataclasses.py (and tests on that version passed with it removed). This makes me wary :-)

This is basically a continuation of #96151, where fixing this was welcomed in https://github.com/python/cpython/pull/98143#issuecomment-1280306360
This commit is contained in:
Shantanu 2023-03-25 14:40:11 -07:00 • committed by GitHub
parent 027223db96
commit 718e86671f
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 27 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

19
Lib/dataclasses.py
View file

@ -432,8 +432,8 @@ def _create_fn(name, args, body, *, globals=None, locals=None,
locals = {}
return_annotation = ''
if return_type is not MISSING:
locals['_return_type'] = return_type
return_annotation = '->_return_type'
locals['__dataclass_return_type__'] = return_type
return_annotation = '->__dataclass_return_type__'
args = ','.join(args)
body = '\n'.join(f' {b}' for b in body)
@ -467,14 +467,14 @@ def _field_init(f, frozen, globals, self_name, slots):
# Return the text of the line in the body of __init__ that will
# initialize this field.
default_name = f'_dflt_{f.name}'
default_name = f'__dataclass_dflt_{f.name}__'
if f.default_factory is not MISSING:
if f.init:
# This field has a default factory. If a parameter is
# given, use it. If not, call the factory.
globals[default_name] = f.default_factory
value = (f'{default_name}() '
f'if {f.name} is _HAS_DEFAULT_FACTORY '
f'if {f.name} is __dataclass_HAS_DEFAULT_FACTORY__ '
f'else {f.name}')
else:
# This is a field that's not in the __init__ params, but
@ -535,11 +535,11 @@ def _init_param(f):
elif f.default is not MISSING:
# There's a default, this will be the name that's used to look
# it up.
default = f'=_dflt_{f.name}'
default = f'=__dataclass_dflt_{f.name}__'
elif f.default_factory is not MISSING:
# There's a factory function. Set a marker.
default = '=_HAS_DEFAULT_FACTORY'
return f'{f.name}:_type_{f.name}{default}'
default = '=__dataclass_HAS_DEFAULT_FACTORY__'
return f'{f.name}:__dataclass_type_{f.name}__{default}'
def _init_fn(fields, std_fields, kw_only_fields, frozen, has_post_init,
@ -562,10 +562,9 @@ def _init_fn(fields, std_fields, kw_only_fields, frozen, has_post_init,
raise TypeError(f'non-default argument {f.name!r} '
'follows default argument')
locals = {f'_type_{f.name}': f.type for f in fields}
locals = {f'__dataclass_type_{f.name}__': f.type for f in fields}
locals.update({
'MISSING': MISSING,
'_HAS_DEFAULT_FACTORY': _HAS_DEFAULT_FACTORY,
'__dataclass_HAS_DEFAULT_FACTORY__': _HAS_DEFAULT_FACTORY,
'__dataclass_builtins_object__': object,
})