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.
test stripping of filelogs where the linkrev doesn't always increase
$ echo '[extensions]' >> $HGRCPATH
$ echo 'strip =' >> $HGRCPATH
$ commit()
> {
> hg up -qC null
> count=1
> for i in "$@"; do
> for f in $i; do
> mkdir -p `dirname $f`
> echo $count > $f
> done
> count=`expr $count + 1`
> done
> hg commit -qAm "$*"
> }
2 1 0 2 0 1 2
$ mkdir files
$ cd files
$ hg init orig
$ cd orig
$ commit '201 210'
$ commit '102 120' '210'
$ commit '021'
$ commit '201' '021 120'
$ commit '012 021' '102 201' '120 210'
$ commit '102 120' '012 210' '021 201'
$ commit '201 210' '021 120' '012 102'
$ cd ..
$ hg clone -q -U -r 4 -r 5 -r 6 orig crossed
$ cd crossed
$ for i in 012 021 102 120 201 210; do
> echo $i
> hg debugindex $i
> echo
> done
012
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 1 5d9299349fc0 000000000000 000000000000
2 2 2661d26c6496 000000000000 000000000000
021
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 2 5d9299349fc0 000000000000 000000000000
2 1 2661d26c6496 000000000000 000000000000
102
rev linkrev nodeid p1-nodeid p2-nodeid
0 1 b8e02f643373 000000000000 000000000000
1 0 5d9299349fc0 000000000000 000000000000
2 2 2661d26c6496 000000000000 000000000000
120
rev linkrev nodeid p1-nodeid p2-nodeid
0 1 b8e02f643373 000000000000 000000000000
1 2 5d9299349fc0 000000000000 000000000000
2 0 2661d26c6496 000000000000 000000000000
201
rev linkrev nodeid p1-nodeid p2-nodeid
0 2 b8e02f643373 000000000000 000000000000
1 0 5d9299349fc0 000000000000 000000000000
2 1 2661d26c6496 000000000000 000000000000
210
rev linkrev nodeid p1-nodeid p2-nodeid
0 2 b8e02f643373 000000000000 000000000000
1 1 5d9299349fc0 000000000000 000000000000
2 0 2661d26c6496 000000000000 000000000000
$ cd ..
$ for i in 0 1 2; do
> hg clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 0
saved backup bundle to $TESTTMP/files/0/.hg/strip-backup/cbb8c2f0a2e3-239800b9-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
% Trying to strip revision 1
saved backup bundle to $TESTTMP/files/1/.hg/strip-backup/124ecc0cbec9-6104543f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
% Trying to strip revision 2
saved backup bundle to $TESTTMP/files/2/.hg/strip-backup/f6439b304a1a-c6505a5f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
$ cd ..
Do a similar test where the manifest revlog has unordered linkrevs
$ mkdir manifests
$ cd manifests
$ hg init orig
$ cd orig
$ commit 'file'
$ commit 'other'
$ commit '' 'other'
$ HGUSER=another-user; export HGUSER
$ commit 'file'
$ commit 'other' 'file'
$ cd ..
$ hg clone -q -U -r 1 -r 2 -r 3 -r 4 orig crossed
$ cd crossed
$ hg debugindex --manifest
rev linkrev nodeid p1-nodeid p2-nodeid
0 2 6bbc6fee55c2 000000000000 000000000000
1 0 1c556153fe54 000000000000 000000000000
2 1 1f76dba919fd 000000000000 000000000000
3 3 bbee06ad59d5 000000000000 000000000000
$ cd ..
$ for i in 2 3; do
> hg clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 2
saved backup bundle to $TESTTMP/manifests/2/.hg/strip-backup/f3015ad03c03-4d98bdc2-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 3 changes to 2 files
% Trying to strip revision 3
saved backup bundle to $TESTTMP/manifests/3/.hg/strip-backup/9632aa303aa4-69192e3f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 3 changes to 2 files
$ cd ..
Now a similar test for a non-root manifest revlog
$ cat >> $HGRCPATH <<EOF
> [experimental]
> treemanifests = yes
> EOF
$ mkdir treemanifests
$ cd treemanifests
$
$ hg --config experimental.treemanifest=True init orig
$ cd orig
$ commit 'dir/file'
$ commit 'dir/other'
$ commit '' 'dir/other'
$ HGUSER=yet-another-user; export HGUSER
$ commit 'otherdir dir/file'
$ commit 'otherdir dir/other' 'otherdir dir/file'
$ cd ..
$ hg --config experimental.treemanifest=True clone -q -U -r 1 -r 2 -r 3 -r 4 orig crossed
$ cd crossed
$ hg debugindex --dir dir
rev linkrev nodeid p1-nodeid p2-nodeid
0 2 6bbc6fee55c2 000000000000 000000000000
1 0 1c556153fe54 000000000000 000000000000
2 1 1f76dba919fd 000000000000 000000000000
3 3 bbee06ad59d5 000000000000 000000000000
$ cd ..
$ for i in 2 3; do
> hg --config experimental.treemanifest=True clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 2
saved backup bundle to $TESTTMP/treemanifests/2/.hg/strip-backup/145f5c75f9ac-a105cfbe-backup.hg
% Verifying
checking changesets
checking manifests
checking directory manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 4 changes to 3 files
% Trying to strip revision 3
saved backup bundle to $TESTTMP/treemanifests/3/.hg/strip-backup/e4e3de5c3cb2-f4c70376-backup.hg
% Verifying
checking changesets
checking manifests
checking directory manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 4 changes to 3 files
$ cd ..