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.
$ . "$TESTDIR/histedit-helpers.sh"
$ cat >> $HGRCPATH <<EOF
> [extensions]
> histedit=
> EOF
$ modwithdate ()
> {
> echo $1 > $1
> hg ci -m $1 -d "$2 0"
> }
$ initrepo ()
> {
> hg init $1
> cd $1
> for x in a b c d e f ; do
> echo $x$x$x$x$x > $x
> hg add $x
> done
> hg ci -m 'Initial commit'
> modwithdate a 1
> modwithdate b 2
> modwithdate c 3
> modwithdate d 4
> modwithdate e 5
> modwithdate f 6
> echo 'I can haz no commute' > e
> hg ci -m 'does not commute with e' -d '7 0'
> cd ..
> }
$ initrepo r
$ cd r
Initial generation of the command files
$ EDITED="$TESTTMP/editedhistory"
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
$ hg log --template 'fold {node|short} {rev} {desc}\n' -r 7 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
$ cat $EDITED
pick 092e4ce14829 3 c
pick ae78f4c9d74f 4 d
fold 42abbb61bede 7 does not commute with e
pick 7f3755409b00 5 e
pick dd184f2faeb0 6 f
log before edit
$ hg log --graph
@ changeset: 7:42abbb61bede
| tag: tip
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: does not commute with e
|
o changeset: 6:dd184f2faeb0
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 5:7f3755409b00
| user: test
| date: Thu Jan 01 00:00:05 1970 +0000
| summary: e
|
o changeset: 4:ae78f4c9d74f
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
edit the history
$ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (fold 42abbb61bede)
(hg histedit --continue to resume)
fix up
$ echo 'I can haz no commute' > e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ HGEDITOR=cat hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
d
***
does not commute with e
HG: Enter commit message. Lines beginning with 'HG:' are removed.
HG: Leave message empty to abort commit.
HG: --
HG: user: test
HG: branch 'default'
HG: changed d
HG: changed e
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7f3755409b00)
(hg histedit --continue to resume)
just continue this time
keep the non-commuting change, and thus the pending change will be dropped
$ hg revert -r 'p1()' e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg diff
$ hg histedit --continue 2>&1 | fixbundle
7f3755409b00: skipping changeset (no changes)
log after edit
$ hg log --graph
@ changeset: 5:1300355b1a54
| tag: tip
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 4:e2ac33269083
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
contents of e
$ hg cat e
I can haz no commute
manifest
$ hg manifest
a
b
c
d
e
f
$ cd ..
Repeat test using "roll", not "fold". "roll" folds in changes but drops message and date
$ initrepo r2
$ cd r2
Initial generation of the command files
$ EDITED="$TESTTMP/editedhistory.2"
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
$ hg log --template 'roll {node|short} {rev} {desc}\n' -r 7 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
$ cat $EDITED
pick 092e4ce14829 3 c
pick ae78f4c9d74f 4 d
roll 42abbb61bede 7 does not commute with e
pick 7f3755409b00 5 e
pick dd184f2faeb0 6 f
log before edit
$ hg log --graph
@ changeset: 7:42abbb61bede
| tag: tip
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: does not commute with e
|
o changeset: 6:dd184f2faeb0
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 5:7f3755409b00
| user: test
| date: Thu Jan 01 00:00:05 1970 +0000
| summary: e
|
o changeset: 4:ae78f4c9d74f
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
edit the history
$ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (roll 42abbb61bede)
(hg histedit --continue to resume)
fix up
$ echo 'I can haz no commute' > e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7f3755409b00)
(hg histedit --continue to resume)
just continue this time
$ hg revert -r 'p1()' e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle
7f3755409b00: skipping changeset (no changes)
log after edit
$ hg log --graph
@ changeset: 5:b538bcb461be
| tag: tip
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 4:317e37cb6d66
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
contents of e
$ hg cat e
I can haz no commute
manifest
$ hg manifest
a
b
c
d
e
f
description is taken from rollup target commit
$ hg log --debug --rev 4
changeset: 4:317e37cb6d66c1c84628c00e5bf4c8c292831951
phase: draft
parent: 3:092e4ce14829f4974399ce4316d59f64ef0b6725
parent: -1:0000000000000000000000000000000000000000
manifest: 4:b068a323d969f22af1296ec6a5ea9384cef437ac
user: test
date: Thu Jan 01 00:00:04 1970 +0000
files: d e
extra: branch=default
extra: histedit_source=ae78f4c9d74ffa4b6cb5045001c303fe9204e890,42abbb61bede6f4366fa1e74a664343e5d558a70
description:
d
done with repo r2
$ cd ..