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
$ mkdir inside
$ echo inside > inside/f1
$ mkdir outside
$ echo outside > outside/f1
$ hg ci -Aqm 'initial'
$ echo modified > inside/f1
$ hg ci -qm 'modify inside'
$ echo modified > outside/f1
$ hg ci -qm 'modify outside'
$ cd ..
(The lfs extension does nothing here, but this test ensures that its hook that
determines whether to add the lfs requirement, respects the narrow boundaries.)
$ hg --config extensions.lfs= clone --narrow ssh://user@dummy/master narrow \
> --include inside
requesting all changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 2 changes to 1 files
new changesets *:* (glob)
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd narrow
$ hg update -q 0
Can not modify dirstate outside
$ mkdir outside
$ touch outside/f1
$ hg debugwalk -v -I 'relglob:f1'
* matcher:
<includematcher includes='(?:|.*/)f1(?:/|$)'>
f inside/f1 inside/f1
$ hg add .
$ hg add outside/f1
abort: cannot track 'outside/f1' - it is outside the narrow clone
[255]
$ touch outside/f3
$ hg add outside/f3
abort: cannot track 'outside/f3' - it is outside the narrow clone
[255]
But adding a truly excluded file shouldn't count
$ hg add outside/f3 -X outside/f3
$ rm -r outside
Can modify dirstate inside
$ echo modified > inside/f1
$ touch inside/f3
$ hg add inside/f3
$ hg status
M inside/f1
A inside/f3
$ hg revert -qC .
$ rm inside/f3
Can commit changes inside. Leaves outside unchanged.
$ hg update -q 'desc("initial")'
$ echo modified2 > inside/f1
$ hg manifest --debug
4d6a634d5ba06331a60c29ee0db8412490a54fcd 644 inside/f1
7fb3bb6356d28d4dc352c5ba52d7350a81b6bd46 644 outside/f1 (flat !)
d0f2f706468ab0e8bec7af87446835fb1b13511b 755 d outside/ (tree !)
$ hg commit -m 'modify inside/f1'
created new head
$ hg files -r .
inside/f1
$ hg manifest --debug
3f4197b4a11b9016e77ebc47fe566944885fd11b 644 inside/f1
7fb3bb6356d28d4dc352c5ba52d7350a81b6bd46 644 outside/f1 (flat !)
d0f2f706468ab0e8bec7af87446835fb1b13511b 755 d outside/ (tree !)
Some filesystems (notably FAT/exFAT only store timestamps with 2
seconds of precision, so by sleeping for 3 seconds, we can ensure that
the timestamps of files stored by dirstate will appear older than the
dirstate file, and therefore we'll be able to get stable output from
debugdirstate. If we don't do this, the test can be slightly flaky.
$ sleep 3
$ hg status
$ hg debugdirstate --no-dates
n 644 10 set inside/f1
Can commit empty files
$ touch inside/c; hg add inside/c; hg commit -qm _; hg verify -q
$ hg cat -r . inside/c