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.
Tests of 'hg status --rev <rev>' to make sure status between <rev> and '.' get
combined correctly with the dirstate status.
$ hg init
First commit
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 1
$ hg addremove --similarity 0
adding content1_content1_content1-tracked
adding content1_content1_content1-untracked
adding content1_content1_content3-tracked
adding content1_content1_content3-untracked
adding content1_content1_missing-tracked
adding content1_content1_missing-untracked
adding content1_content2_content1-tracked
adding content1_content2_content1-untracked
adding content1_content2_content2-tracked
adding content1_content2_content2-untracked
adding content1_content2_content3-tracked
adding content1_content2_content3-untracked
adding content1_content2_missing-tracked
adding content1_content2_missing-untracked
adding content1_missing_content1-tracked
adding content1_missing_content1-untracked
adding content1_missing_content3-tracked
adding content1_missing_content3-untracked
adding content1_missing_missing-tracked
adding content1_missing_missing-untracked
$ hg commit -m first
Second commit
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 2
$ hg addremove --similarity 0
removing content1_missing_content1-tracked
removing content1_missing_content1-untracked
removing content1_missing_content3-tracked
removing content1_missing_content3-untracked
removing content1_missing_missing-tracked
removing content1_missing_missing-untracked
adding missing_content2_content2-tracked
adding missing_content2_content2-untracked
adding missing_content2_content3-tracked
adding missing_content2_content3-untracked
adding missing_content2_missing-tracked
adding missing_content2_missing-untracked
$ hg commit -m second
Working copy
$ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 2 wc
$ hg addremove --similarity 0
adding content1_missing_content1-tracked
adding content1_missing_content1-untracked
adding content1_missing_content3-tracked
adding content1_missing_content3-untracked
adding content1_missing_missing-tracked
adding content1_missing_missing-untracked
adding missing_missing_content3-tracked
adding missing_missing_content3-untracked
adding missing_missing_missing-tracked
adding missing_missing_missing-untracked
$ hg forget *_*_*-untracked
$ rm *_*_missing-*
Status compared to parent of the working copy, i.e. the dirstate status
$ hg status -A --rev 1 'glob:missing_content2_content3-tracked'
M missing_content2_content3-tracked
$ hg status -A --rev 1 'glob:missing_content2_content2-tracked'
C missing_content2_content2-tracked
$ hg status -A --rev 1 'glob:missing_missing_content3-tracked'
A missing_missing_content3-tracked
$ hg status -A --rev 1 'glob:missing_missing_content3-untracked'
? missing_missing_content3-untracked
$ hg status -A --rev 1 'glob:missing_content2_*-untracked'
R missing_content2_content2-untracked
R missing_content2_content3-untracked
R missing_content2_missing-untracked
$ hg status -A --rev 1 'glob:missing_*_missing-tracked'
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg status -A --rev 1 'glob:missing_missing_missing-untracked'
missing_missing_missing-untracked: $ENOENT$
Status between first and second commit. Should ignore dirstate status.
$ hg status -A --rev 0:1 'glob:content1_content2_*'
M content1_content2_content1-tracked
M content1_content2_content1-untracked
M content1_content2_content2-tracked
M content1_content2_content2-untracked
M content1_content2_content3-tracked
M content1_content2_content3-untracked
M content1_content2_missing-tracked
M content1_content2_missing-untracked
$ hg status -A --rev 0:1 'glob:content1_content1_*'
C content1_content1_content1-tracked
C content1_content1_content1-untracked
C content1_content1_content3-tracked
C content1_content1_content3-untracked
C content1_content1_missing-tracked
C content1_content1_missing-untracked
$ hg status -A --rev 0:1 'glob:missing_content2_*'
A missing_content2_content2-tracked
A missing_content2_content2-untracked
A missing_content2_content3-tracked
A missing_content2_content3-untracked
A missing_content2_missing-tracked
A missing_content2_missing-untracked
$ hg status -A --rev 0:1 'glob:content1_missing_*'
R content1_missing_content1-tracked
R content1_missing_content1-untracked
R content1_missing_content3-tracked
R content1_missing_content3-untracked
R content1_missing_missing-tracked
R content1_missing_missing-untracked
$ hg status -A --rev 0:1 'glob:missing_missing_*'
Status compared to one revision back, checking that the dirstate status
is correctly combined with the inter-revision status
$ hg status -A --rev 0 'glob:content1_*_content[23]-tracked'
M content1_content1_content3-tracked
M content1_content2_content2-tracked
M content1_content2_content3-tracked
M content1_missing_content3-tracked
$ hg status -A --rev 0 'glob:content1_*_content1-tracked'
C content1_content1_content1-tracked
C content1_content2_content1-tracked
C content1_missing_content1-tracked
$ hg status -A --rev 0 'glob:missing_*_content?-tracked'
A missing_content2_content2-tracked
A missing_content2_content3-tracked
A missing_missing_content3-tracked
BROKEN: missing_content2_content[23]-untracked exist, so should be listed
$ hg status -A --rev 0 'glob:missing_*_content?-untracked'
? missing_missing_content3-untracked
$ hg status -A --rev 0 'glob:content1_*_*-untracked'
R content1_content1_content1-untracked
R content1_content1_content3-untracked
R content1_content1_missing-untracked
R content1_content2_content1-untracked
R content1_content2_content2-untracked
R content1_content2_content3-untracked
R content1_content2_missing-untracked
R content1_missing_content1-untracked
R content1_missing_content3-untracked
R content1_missing_missing-untracked
$ hg status -A --rev 0 'glob:*_*_missing-tracked'
! content1_content1_missing-tracked
! content1_content2_missing-tracked
! content1_missing_missing-tracked
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg status -A --rev 0 'glob:missing_*_missing-untracked'