view contrib/examples/fix.hgrc @ 45095:8e04607023e5

procutil: ensure that procutil.std{out,err}.write() writes all bytes

Python 3 offers different kind of streams and it’s not guaranteed for all of
them that calling write() writes all bytes.

When Python is started in unbuffered mode, sys.std{out,err}.buffer are
instances of io.FileIO, whose write() can write less bytes for
platform-specific reasons (e.g. Linux has a 0x7ffff000 bytes maximum and could
write less if interrupted by a signal; when writing to Windows consoles, it’s
limited to 32767 bytes to avoid the "not enough space" error). This can lead to
silent loss of data, both when using sys.std{out,err}.buffer (which may in fact
not be a buffered stream) and when using the text streams sys.std{out,err}
(I’ve created a CPython bug report for that:
https://bugs.python.org/issue41221).

Python may fix the problem at some point. For now, we implement our own wrapper
for procutil.std{out,err} that calls the raw stream’s write() method until all
bytes have been written. We don’t use sys.std{out,err} for larger writes, so I
think it’s not worth the effort to patch them.

[fix]
clang-format:command = clang-format --style file
clang-format:pattern = set:(**.c or **.cc or **.h) and not "include:contrib/clang-format-ignorelist"

rustfmt:command = rustfmt +nightly
rustfmt:pattern = set:**.rs

black:command = black --config=black.toml -
black:pattern = set:**.py - mercurial/thirdparty/**

# Mercurial doesn't have any Go code, but if we did this is how we
# would configure `hg fix` for Go:
go:command = gofmt
go:pattern = set:**.go