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.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> rebase=
>
> [phases]
> publish=False
>
> [alias]
> tglog = log -G --template "{rev}:{phase} '{desc}' {branches}\n"
> EOF
$ hg init a
$ cd a
$ echo A > A
$ hg add A
$ hg ci -m A
$ echo 'B' > B
$ hg add B
$ hg ci -m B
$ echo C >> A
$ hg ci -m C
$ hg up -q -C 0
$ echo D >> A
$ hg ci -m D
created new head
$ echo E > E
$ hg add E
$ hg ci -m E
$ hg up -q -C 0
$ hg branch 'notdefault'
marked working directory as branch notdefault
(branches are permanent and global, did you want a bookmark?)
$ echo F >> A
$ hg ci -m F
$ cd ..
Rebasing B onto E - check keep: and phases
$ hg clone -q -u . a a1
$ cd a1
$ hg phase --force --secret 2
$ hg tglog
@ 5:draft 'F' notdefault
|
| o 4:draft 'E'
| |
| o 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ hg rebase -s 1 -d 4 --keep
rebasing 1:27547f69f254 "B"
rebasing 2:965c486023db "C"
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
[240]
Solve the conflict and go on:
$ echo 'conflict solved' > A
$ rm A.orig
$ hg resolve -m A
(no more unresolved files)
continue: hg rebase --continue
$ hg rebase --continue
already rebased 1:27547f69f254 "B" as 45396c49d53b
rebasing 2:965c486023db "C"
$ hg tglog
o 7:secret 'C'
|
o 6:draft 'B'
|
| @ 5:draft 'F' notdefault
| |
o | 4:draft 'E'
| |
o | 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ cd ..
Rebase F onto E - check keepbranches:
$ hg clone -q -u . a a2
$ cd a2
$ hg phase --force --secret 2
$ hg tglog
@ 5:draft 'F' notdefault
|
| o 4:draft 'E'
| |
| o 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ hg rebase -s 5 -d 4 --keepbranches
rebasing 5:01e6ebbd8272 tip "F"
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
[240]
Solve the conflict and go on:
$ echo 'conflict solved' > A
$ rm A.orig
$ hg resolve -m A
(no more unresolved files)
continue: hg rebase --continue
$ hg rebase --continue
rebasing 5:01e6ebbd8272 tip "F"
saved backup bundle to $TESTTMP/a2/.hg/strip-backup/01e6ebbd8272-6fd3a015-rebase.hg
$ hg tglog
@ 5:draft 'F' notdefault
|
o 4:draft 'E'
|
o 3:draft 'D'
|
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ cat >> .hg/hgrc << EOF
> [experimental]
> evolution.createmarkers=True
> EOF
When updating away from a dirty, obsolete wdir, don't complain that the old p1
is filtered and requires --hidden.
$ echo conflict > A
$ hg debugobsolete 071d07019675449d53b7e312c65bcf28adbbdb64 965c486023dbfdc9c32c52dc249a231882fd5c17
1 new obsolescence markers
obsoleted 1 changesets
$ hg update -r 2 --config ui.merge=internal:merge --merge
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
1 files updated, 0 files merged, 1 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges
[1]
$ hg resolve A
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
[1]
An unresolved conflict will pin the obsolete revision
$ hg log -G -Tcompact
% 5[tip] 071d07019675 1970-01-01 00:00 +0000 test
| F
|
o 4 ae36e8e3dfd7 1970-01-01 00:00 +0000 test
| E
|
o 3:0 46b37eabc604 1970-01-01 00:00 +0000 test
| D
|
| @ 2 965c486023db 1970-01-01 00:00 +0000 test
| | C
| |
| o 1 27547f69f254 1970-01-01 00:00 +0000 test
|/ B
|
o 0 4a2df7238c3b 1970-01-01 00:00 +0000 test
A
But resolving the conflicts will unpin it
$ hg resolve -m A
(no more unresolved files)
$ hg log -G -Tcompact
o 4[tip] ae36e8e3dfd7 1970-01-01 00:00 +0000 test
| E
|
o 3:0 46b37eabc604 1970-01-01 00:00 +0000 test
| D
|
| @ 2 965c486023db 1970-01-01 00:00 +0000 test
| | C
| |
| o 1 27547f69f254 1970-01-01 00:00 +0000 test
|/ B
|
o 0 4a2df7238c3b 1970-01-01 00:00 +0000 test
A
$ hg up -C -q .
$ cd ..