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.
#testcases flat tree
$ . "$TESTDIR/narrow-library.sh"
#if tree
$ cat << EOF >> $HGRCPATH
> [experimental]
> treemanifest = 1
> EOF
#endif
create full repo
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [narrow]
> serveellipses=True
> EOF
$ mkdir inside
$ echo inside1 > inside/f1
$ echo inside2 > inside/f2
$ mkdir outside
$ echo outside1 > outside/f1
$ echo outside2 > outside/f2
$ hg ci -Aqm 'initial'
$ echo modified > inside/f1
$ hg ci -qm 'modify inside/f1'
$ hg update -q 0
$ echo modified > inside/f2
$ hg ci -qm 'modify inside/f2'
$ hg update -q 0
$ echo modified2 > inside/f1
$ hg ci -qm 'conflicting inside/f1'
$ hg update -q 0
$ echo modified > outside/f1
$ hg ci -qm 'modify outside/f1'
$ hg update -q 0
$ echo modified2 > outside/f1
$ hg ci -qm 'conflicting outside/f1'
$ cd ..
$ hg clone --narrow ssh://user@dummy/master narrow --include inside
requesting all changes
adding changesets
adding manifests
adding file changes
added 6 changesets with 5 changes to 2 files (+4 heads)
new changesets *:* (glob)
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd narrow
$ hg update -q 0
Can merge in when no files outside narrow spec are involved
$ hg update -q 'desc("modify inside/f1")'
$ hg merge 'desc("modify inside/f2")'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m 'merge inside changes'
Can merge conflicting changes inside narrow spec
$ hg update -q 'desc("modify inside/f1")'
$ hg merge 'desc("conflicting inside/f1")' 2>&1 | egrep -v '(warning:|incomplete!)'
merging inside/f1
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
$ echo modified3 > inside/f1
$ hg resolve -m
(no more unresolved files)
$ hg commit -m 'merge inside/f1'
TODO: Can merge non-conflicting changes outside narrow spec
$ hg update -q 'desc("modify inside/f1")'
#if flat
$ hg merge 'desc("modify outside/f1")'
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
status should be clean
$ hg status
? inside/f1.orig
file out of the spec should still not be in the dirstate at all
$ hg debugdirstate | grep outside/f1
[1]
Commit that merge
$ hg ci -m 'merge from outside to inside'
status should be clean
$ hg status
? inside/f1.orig
file out of the spec should not be in the mergestate anymore
$ hg debugmergestate | grep outside/f1
[1]
file out of the spec should still not be in the dirstate at all
$ hg debugdirstate | grep outside/f1
[1]
The filenode used should come from p2
$ hg manifest --debug --rev . | grep outside/f1
83cd11431a3b2aff8a3995e5f27bcf33cdb5be98 644 outside/f1
$ hg manifest --debug --rev 'p1(.)' | grep outside/f1
c6b956c48be2cd4fa94be16002aba311143806fa 644 outside/f1
$ hg manifest --debug --rev 'p2(.)' | grep outside/f1
83cd11431a3b2aff8a3995e5f27bcf33cdb5be98 644 outside/f1
remove the commit to get in the previous situation again
$ hg debugstrip -r .
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/narrow/.hg/strip-backup/48eb25338b19-a1bb8350-backup.hg
#else
$ hg merge 'desc("modify outside/f1")'
abort: merge affects file 'outside/' outside narrow, which is not yet supported (tree !)
(merging in the other direction may work)
[255]
#endif
$ hg update -q 'desc("modify outside/f1")'
$ hg merge 'desc("modify inside/f1")'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci -m 'merge from inside to outside'
Refuses merge of conflicting outside changes
$ hg update -q 'desc("modify outside/f1")'
$ hg merge 'desc("conflicting outside/f1")'
abort: conflict in file 'outside/f1' is outside narrow clone (flat !)
abort: conflict in file 'outside/' is outside narrow clone (tree !)
[20]