typing: add a fake `__init__()` to bytestr to distract pytype
I'm not sure what changed before pytype 09-09-2021 (from 04-15-2021), but these
started getting flagged. This wrapping an exception in a `bytestr` pattern has
been flagged before, and I've fixed it then with `stringutil.forcebytestr()`.
But that doesn't work here, because it would create a circular import.
I suspect the issue is `bytes.__new__()` wants `Iterable[int]`, so it just
assumes the subclass will also take that. The referenced pytype bug isn't an
exact match, but seems related and the suggested workaround helps.
The specific warnings fixed are:
File "/mnt/c/Users/Matt/hg/mercurial/encoding.py", line 212, in tolocal: Function bytestr.__init__ was called with the wrong arguments [wrong-arg-types]
Expected: (self, ints: Iterable[int])
Actually passed: (self, ints: LookupError)
Attributes of protocol Iterable[int] are not implemented on LookupError: __iter__
Called from (traceback):
line 353, in current file
File "/mnt/c/Users/Matt/hg/mercurial/encoding.py", line 240, in fromlocal: Function bytestr.__init__ was called with the wrong arguments [wrong-arg-types]
Expected: (self, ints: Iterable[int])
Actually passed: (self, ints: UnicodeDecodeError)
Attributes of protocol Iterable[int] are not implemented on UnicodeDecodeError: __iter__
Differential Revision: https://phab.mercurial-scm.org/D11466
--- a/mercurial/pycompat.py Mon Sep 20 15:51:23 2021 -0400
+++ b/mercurial/pycompat.py Tue Sep 21 00:16:35 2021 -0400
@@ -222,6 +222,15 @@
>>> assert type(t) is bytes
"""
+ # Trick pytype into not demanding Iterable[int] be passed to __new__(),
+ # since the appropriate bytes format is done internally.
+ #
+ # https://github.com/google/pytype/issues/500
+ if TYPE_CHECKING:
+
+ def __init__(self, s=b''):
+ pass
+
def __new__(cls, s=b''):
if isinstance(s, bytestr):
return s