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
$ 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'
> for x in a b c d e f ; do
> echo $x > $x
> hg ci -m $x
> done
> echo 'I can haz no commute' > e
> hg ci -m 'does not commute with e'
> cd ..
> }
$ initrepo r1
$ cd r1
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 'pick {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 65a9a84f33fd 3 c
pick 00f1c5383965 4 d
pick 39522b764e3d 7 does not commute with e
pick 7b4e2f4b7bcd 5 e
pick 500cac37a696 6 f
log before edit
$ hg log --graph
@ changeset: 7:39522b764e3d
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: does not commute with e
|
o changeset: 6:500cac37a696
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 5:7b4e2f4b7bcd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: e
|
o changeset: 4:00f1c5383965
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 3:65a9a84f33fd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 2:da6535b52e45
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 1:c1f09da44841
| user: test
| date: Thu Jan 01 00:00:00 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 (pick 39522b764e3d)
(hg histedit --continue to resume)
abort the edit
$ hg histedit --abort 2>&1 | fixbundle
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
second edit set
$ hg log --graph
@ changeset: 7:39522b764e3d
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: does not commute with e
|
o changeset: 6:500cac37a696
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 5:7b4e2f4b7bcd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: e
|
o changeset: 4:00f1c5383965
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 3:65a9a84f33fd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 2:da6535b52e45
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 1:c1f09da44841
| user: test
| date: Thu Jan 01 00:00:00 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 (pick 39522b764e3d)
(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
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7b4e2f4b7bcd)
(hg histedit --continue to resume)
We forcibly enable curses here so we can verify that continuing works
with curses enabled.
$ hg histedit --continue --config ui.interactive=true \
> --config ui.interface=curses 2>&1 | fixbundle
abort: unresolved merge conflicts (see 'hg help resolve')
This failure is caused by 7b4e2f4b7bcd "e" not rebasing the non commutative
former children.
just continue this time
$ hg revert -r 'p1()' e
make sure the to-be-empty commit doesn't screw up the state (issue5545)
$ hg histedit --continue 2>&1 | fixbundle
abort: unresolved merge conflicts (see 'hg help resolve')
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle
7b4e2f4b7bcd: skipping changeset (no changes)
log after edit
$ hg log --graph
@ changeset: 6:7efe1373e4bc
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 5:e334d87a1e55
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: does not commute with e
|
o changeset: 4:00f1c5383965
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 3:65a9a84f33fd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 2:da6535b52e45
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 1:c1f09da44841
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
start over
$ cd ..
$ initrepo r2
$ cd r2
$ rm $EDITED
$ 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 'mess {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 65a9a84f33fd 3 c
pick 00f1c5383965 4 d
mess 39522b764e3d 7 does not commute with e
pick 7b4e2f4b7bcd 5 e
pick 500cac37a696 6 f
edit the history, this time with a fold action
$ 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 (mess 39522b764e3d)
(hg histedit --continue to resume)
$ 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
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7b4e2f4b7bcd)
(hg histedit --continue to resume)
second edit also fails, but just continue
$ hg revert -r 'p1()' e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle
7b4e2f4b7bcd: skipping changeset (no changes)
post message fix
$ hg log --graph
@ changeset: 6:7efe1373e4bc
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 5:e334d87a1e55
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: does not commute with e
|
o changeset: 4:00f1c5383965
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 3:65a9a84f33fd
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 2:da6535b52e45
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 1:c1f09da44841
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
An invalid editor shouldn't leave the user in a broken state:
$ EDITOR=totally-not-a-thing-unsensible-editor-value hg histedit 4
$ cd ..