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.
$ hg init repo
$ cd repo
$ hg init subrepo
$ echo a > subrepo/a
$ hg -R subrepo ci -Am adda
adding a
$ echo 'subrepo = subrepo' > .hgsub
$ hg ci -Am addsubrepo
adding .hgsub
$ echo b > subrepo/b
$ hg -R subrepo ci -Am addb
adding b
$ hg ci -m updatedsub
ignore blanklines in .hgsubstate
>>> open('.hgsubstate', 'wb').write(b'\n\n \t \n \n') and None
$ hg st --subrepos
M .hgsubstate
$ hg revert -qC .hgsubstate
abort more gracefully on .hgsubstate parsing error
$ cp .hgsubstate .hgsubstate.old
>>> open('.hgsubstate', 'wb').write(b'\ninvalid') and None
$ hg st --subrepos --cwd $TESTTMP -R $TESTTMP/repo
abort: invalid subrepository revision specifier in 'repo/.hgsubstate' line 2
[255]
$ mv .hgsubstate.old .hgsubstate
delete .hgsub and revert it
$ rm .hgsub
$ hg revert .hgsub
warning: subrepo spec file '.hgsub' not found
warning: subrepo spec file '.hgsub' not found
delete .hgsubstate and revert it
$ rm .hgsubstate
$ hg revert .hgsubstate
delete .hgsub and update
$ rm .hgsub
$ hg up 0 --cwd $TESTTMP -R $TESTTMP/repo
warning: subrepo spec file 'repo/.hgsub' not found
warning: subrepo spec file 'repo/.hgsub' not found
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
warning: subrepo spec file '.hgsub' not found
! .hgsub
$ ls -A subrepo
.hg
a
delete .hgsubstate and update
$ hg up -C
warning: subrepo spec file '.hgsub' not found
warning: subrepo spec file '.hgsub' not found
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm .hgsubstate
$ hg up 0
other [destination] changed .hgsubstate which local [working copy] deleted
use (c)hanged version or leave (d)eleted? c
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
$ ls -A subrepo
.hg
a
Enable obsolete
$ cat >> $HGRCPATH << EOF
> [ui]
> logtemplate= {rev}:{node|short} {desc|firstline}
> [phases]
> publish=False
> [experimental]
> evolution.createmarkers=True
> EOF
check that we can update parent repo with missing (amended) subrepo revision
$ hg up --repository subrepo -r tip
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg ci -m "updated subrepo to tip"
created new head
$ cd subrepo
$ hg update -r tip
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo foo > a
$ hg commit --amend -m "addb (amended)"
$ cd ..
$ hg update --clean .
revision 102a90ea7b4a in subrepository "subrepo" is hidden
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
check that --hidden is propagated to the subrepo
$ hg -R subrepo up tip
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg ci -m 'commit with amended subrepo'
$ echo bar > subrepo/a
$ hg -R subrepo ci --amend -m "amend a (again)"
$ hg --hidden cat subrepo/a
foo
verify will warn if locked-in subrepo revisions are hidden or missing
$ hg ci -m "amended subrepo (again)"
$ hg --config extensions.strip= --hidden strip -R subrepo -qr 'tip' --config devel.strip-obsmarkers=no
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 5 changesets with 5 changes to 2 files
checking subrepo links
subrepo 'subrepo' is hidden in revision a66de08943b6
subrepo 'subrepo' is hidden in revision 674d05939c1e
subrepo 'subrepo' not found in revision a7d05d9055a4
verifying shouldn't init a new subrepo if the reference doesn't exist
$ mv subrepo b
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 5 changesets with 5 changes to 2 files
checking subrepo links
0: repository $TESTTMP/repo/subrepo not found
1: repository $TESTTMP/repo/subrepo not found
3: repository $TESTTMP/repo/subrepo not found
4: repository $TESTTMP/repo/subrepo not found
$ ls -A
.hg
.hgsub
.hgsubstate
b
$ mv b subrepo
$ cd ..