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.
# Create server
$ hg init server
$ cd server
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
$ cd ../
# Clone server and enable extensions
$ hg clone -q server client
$ cd client
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
# Commit file that will trigger the noop extension
$ echo '[NOOP]' > noop
$ hg commit -Aqm "noop"
# Commit file that will trigger the base64 extension
$ echo '[BASE64]' > base64
$ hg commit -Aqm 'base64'
# Commit file that will trigger the gzip extension
$ echo '[GZIP]' > gzip
$ hg commit -Aqm 'gzip'
# Commit file that will trigger noop and base64
$ echo '[NOOP][BASE64]' > noop-base64
$ hg commit -Aqm 'noop+base64'
# Commit file that will trigger noop and gzip
$ echo '[NOOP][GZIP]' > noop-gzip
$ hg commit -Aqm 'noop+gzip'
# Commit file that will trigger base64 and gzip
$ echo '[BASE64][GZIP]' > base64-gzip
$ hg commit -Aqm 'base64+gzip'
# Commit file that will trigger base64, gzip and noop
$ echo '[BASE64][GZIP][NOOP]' > base64-gzip-noop
$ hg commit -Aqm 'base64+gzip+noop'
# TEST: ensure the revision data is consistent
$ hg cat noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r . base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r . gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r . noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r . noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r . base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r . base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# Push to the server
$ hg push
pushing to $TESTTMP/server
searching for changes
adding changesets
adding manifests
adding file changes
added 7 changesets with 7 changes to 7 files
Ensure the data got to the server OK
$ cd ../server
$ hg cat -r 6e48f4215d24 noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r 6e48f4215d24 base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r 6e48f4215d24 gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r 6e48f4215d24 noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r 6e48f4215d24 noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r 6e48f4215d24 base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r 6e48f4215d24 base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# Initialize new client (not cloning) and setup extension
$ cd ..
$ hg init client2
$ cd client2
$ cat >> .hg/hgrc << EOF
> [paths]
> default = $TESTTMP/server
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
# Pull from server and update to latest revision
$ hg pull default
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 7 changesets with 7 changes to 7 files
new changesets 07b1b9442c5b:6e48f4215d24
(run 'hg update' to get a working copy)
$ hg update
7 files updated, 0 files merged, 0 files removed, 0 files unresolved
# TEST: ensure the revision data is consistent
$ hg cat noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r . base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r . gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r . noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r . noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r . base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r . base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# TEST: ensure a missing processor is handled
$ echo '[FAIL][BASE64][GZIP][NOOP]' > fail-base64-gzip-noop
$ hg commit -Aqm 'fail+base64+gzip+noop'
abort: missing processor for flag '0x1'
[50]
$ rm fail-base64-gzip-noop
# TEST: ensure we cannot register several flag processors on the same flag
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> duplicate=$TESTDIR/flagprocessorext.py
> EOF
$ hg debugrebuilddirstate
Traceback (most recent call last):
File "*/mercurial/extensions.py", line *, in _runextsetup (glob) (no-pyoxidizer !)
File "mercurial.extensions", line *, in _runextsetup (glob) (pyoxidizer !)
extsetup(ui)
File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
flagutil.addflagprocessor( (py38 !)
validatehash, (no-py38 !)
File "*/mercurial/revlogutils/flagutil.py", line *, in addflagprocessor (glob) (no-pyoxidizer !)
File "mercurial.revlogutils.flagutil", line *, in addflagprocessor (glob) (pyoxidizer !)
insertflagprocessor(flag, processor, flagprocessors)
File "*/mercurial/revlogutils/flagutil.py", line *, in insertflagprocessor (glob) (no-pyoxidizer !)
File "mercurial.revlogutils.flagutil", line *, in insertflagprocessor (glob) (pyoxidizer !)
raise error.Abort(msg)
mercurial.error.Abort: cannot register multiple processors on flag '0x8'. (py3 !)
*** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
$ hg st 2>&1 | egrep 'cannot register multiple processors|flagprocessorext'
File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
mercurial.error.Abort: cannot register multiple processors on flag '0x8'. (py3 !)
*** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
File "*/tests/flagprocessorext.py", line *, in b64decode (glob)
$ cd ..
# TEST: bundle repo
$ hg init bundletest
$ cd bundletest
$ cat >> .hg/hgrc << EOF
> [extensions]
> flagprocessor=$TESTDIR/flagprocessorext.py
> EOF
$ for i in 0 single two three 4; do
> echo '[BASE64]a-bit-longer-'$i > base64
> hg commit -m base64-$i -A base64
> done
$ hg update 2 -q
$ echo '[BASE64]a-bit-longer-branching' > base64
$ hg commit -q -m branching
#if repobundlerepo
$ hg bundle --base 1 bundle.hg
4 changesets found
$ hg --config extensions.strip= strip -r 2 --no-backup --force -q
$ hg -R bundle.hg log --stat -T '{rev} {desc}\n' base64
5 branching
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
4 base64-4
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
3 base64-three
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
2 base64-two
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
1 base64-single
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
0 base64-0
base64 | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
$ hg bundle -R bundle.hg --base 1 bundle-again.hg -q
$ hg -R bundle-again.hg log --stat -T '{rev} {desc}\n' base64
5 branching
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
4 base64-4
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
3 base64-three
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
2 base64-two
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
1 base64-single
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
0 base64-0
base64 | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
$ rm bundle.hg bundle-again.hg
#endif
# TEST: hg status
$ hg status
$ hg diff