procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
Test alignment of multibyte characters
$ HGENCODING=utf-8
$ export HGENCODING
$ hg init t
$ cd t
$ "$PYTHON" << EOF
> from mercurial import pycompat
> # (byte, width) = (6, 4)
> s = b"\xe7\x9f\xad\xe5\x90\x8d"
> # (byte, width) = (7, 7): odd width is good for alignment test
> m = b"MIDDLE_"
> # (byte, width) = (18, 12)
> l = b"\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d"
> f = open('s', 'wb'); f.write(s); f.close()
> f = open('m', 'wb'); f.write(m); f.close()
> f = open('l', 'wb'); f.write(l); f.close()
> # instant extension to show list of options
> f = open('showoptlist.py', 'wb'); f.write(b"""# encoding: utf-8
> from mercurial import registrar
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> @command(b'showoptlist',
> [(b's', b'opt1', b'', b'short width' + (b' ' +%(s)s) * 8, %(s)s),
> (b'm', b'opt2', b'', b'middle width' + (b' ' + %(m)s) * 8, %(m)s),
> (b'l', b'opt3', b'', b'long width' + (b' ' + %(l)s) * 8, %(l)s)],
> b'')
> def showoptlist(ui, repo, *pats, **opts):
> '''dummy command to show option descriptions'''
> return 0
> """ % {b's': pycompat.byterepr(s),
> b'm': pycompat.byterepr(m),
> b'l': pycompat.byterepr(l),
> })
> f.close()
> EOF
$ S=`cat s`
$ M=`cat m`
$ L=`cat l`
alignment of option descriptions in help
$ cat <<EOF > .hg/hgrc
> [extensions]
> ja_ext = `pwd`/showoptlist.py
> EOF
check alignment of option descriptions in help
$ hg help showoptlist
hg showoptlist
dummy command to show option descriptions
options:
-s --opt1 \xe7\x9f\xad\xe5\x90\x8d short width \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d (esc)
-m --opt2 MIDDLE_ middle width MIDDLE_ MIDDLE_ MIDDLE_ MIDDLE_ MIDDLE_
MIDDLE_ MIDDLE_ MIDDLE_
-l --opt3 \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d long width \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
(some details hidden, use --verbose to show complete help)
$ rm -f s; touch s
$ rm -f m; touch m
$ rm -f l; touch l
add files
$ cp s $S
$ hg add $S
$ cp m $M
$ hg add $M
$ cp l $L
$ hg add $L
commit(1)
$ echo 'first line(1)' >> s; cp s $S
$ echo 'first line(2)' >> m; cp m $M
$ echo 'first line(3)' >> l; cp l $L
$ hg commit -m 'first commit' -u $S
commit(2)
$ echo 'second line(1)' >> s; cp s $S
$ echo 'second line(2)' >> m; cp m $M
$ echo 'second line(3)' >> l; cp l $L
$ hg commit -m 'second commit' -u $M
commit(3)
$ echo 'third line(1)' >> s; cp s $S
$ echo 'third line(2)' >> m; cp m $M
$ echo 'third line(3)' >> l; cp l $L
$ hg commit -m 'third commit' -u $L
check alignment of user names in annotate
$ hg annotate -u $M
\xe7\x9f\xad\xe5\x90\x8d: first line(2) (esc)
MIDDLE_: second line(2)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d: third line(2) (esc)
check alignment of filenames in diffstat
$ hg diff -c tip --stat
MIDDLE_ | 1 +
\xe7\x9f\xad\xe5\x90\x8d | 1 + (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d | 1 + (esc)
3 files changed, 3 insertions(+), 0 deletions(-)
add branches/tags
$ hg branch $S
marked working directory as branch \xe7\x9f\xad\xe5\x90\x8d (esc)
(branches are permanent and global, did you want a bookmark?)
$ hg tag $S
$ hg book -f $S
$ hg branch $M
marked working directory as branch MIDDLE_
$ hg tag $M
$ hg book -f $M
$ hg branch $L
marked working directory as branch \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
$ hg tag $L
$ hg book -f $L
check alignment of branches
$ hg branches
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 5:d745ff46155b (esc)
MIDDLE_ 4:9259be597f19 (inactive)
\xe7\x9f\xad\xe5\x90\x8d 3:b06c5b6def9e (inactive) (esc)
default 2:64a70663cee8 (inactive)
check alignment of tags
$ hg tags
tip 5:d745ff46155b
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 4:9259be597f19 (esc)
MIDDLE_ 3:b06c5b6def9e
\xe7\x9f\xad\xe5\x90\x8d 2:64a70663cee8 (esc)
check alignment of bookmarks
$ hg book
MIDDLE_ 5:d745ff46155b
\xe7\x9f\xad\xe5\x90\x8d 4:9259be597f19 (esc)
* \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 5:d745ff46155b (esc)