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.
#require no-reposimplestore
Test creating a consuming stream bundle v2
$ getmainid() {
> hg -R main log --template '{node}\n' --rev "$1"
> }
$ cp $HGRCPATH $TESTTMP/hgrc.orig
$ cat >> $HGRCPATH << EOF
> [experimental]
> evolution.createmarkers=True
> evolution.exchange=True
> bundle2-output-capture=True
> [ui]
> logtemplate={rev}:{node|short} {phase} {author} {bookmarks} {desc|firstline}
> [web]
> push_ssl = false
> allow_push = *
> [phases]
> publish=False
> [extensions]
> drawdag=$TESTDIR/drawdag.py
> clonebundles=
> EOF
The extension requires a repo (currently unused)
$ hg init main
$ cd main
$ hg debugdrawdag <<'EOF'
> E
> |
> D
> |
> C
> |
> B
> |
> A
> EOF
$ hg bundle -a --type="none-v2;stream=v2" bundle.hg
$ hg debugbundle bundle.hg
Stream params: {}
stream2 -- {bytecount: 1693, filecount: 11, requirements: generaldelta%2Crevlogv1%2Csparserevlog} (mandatory: True) (no-zstd !)
stream2 -- {bytecount: 1693, filecount: 11, requirements: generaldelta%2Crevlog-compression-zstd%2Crevlogv1%2Csparserevlog} (mandatory: True) (zstd no-rust !)
stream2 -- {bytecount: 1693, filecount: 11, requirements: generaldelta%2Crevlog-compression-zstd%2Crevlogv1%2Csparserevlog} (mandatory: True) (rust !)
$ hg debugbundle --spec bundle.hg
none-v2;stream=v2;requirements%3Dgeneraldelta%2Crevlogv1%2Csparserevlog (no-zstd !)
none-v2;stream=v2;requirements%3Dgeneraldelta%2Crevlog-compression-zstd%2Crevlogv1%2Csparserevlog (zstd no-rust !)
none-v2;stream=v2;requirements%3Dgeneraldelta%2Crevlog-compression-zstd%2Crevlogv1%2Csparserevlog (rust !)
Test that we can apply the bundle as a stream clone bundle
$ cat > .hg/clonebundles.manifest << EOF
> http://localhost:$HGPORT1/bundle.hg BUNDLESPEC=`hg debugbundle --spec bundle.hg`
> EOF
$ hg serve -d -p $HGPORT --pid-file hg.pid --accesslog access.log
$ cat hg.pid >> $DAEMON_PIDS
$ "$PYTHON" $TESTDIR/dumbhttp.py -p $HGPORT1 --pid http.pid
$ cat http.pid >> $DAEMON_PIDS
$ cd ..
$ hg clone http://localhost:$HGPORT streamv2-clone-implicit --debug
using http://localhost:$HGPORT/
sending capabilities command
sending clonebundles command
applying clone bundle from http://localhost:$HGPORT1/bundle.hg
bundle2-input-bundle: with-transaction
bundle2-input-part: "stream2" (params: 3 mandatory) supported
applying stream bundle
11 files to transfer, 1.65 KB of data
starting 4 threads for background file closing (?)
starting 4 threads for background file closing (?)
adding [s] data/A.i (66 bytes)
adding [s] data/B.i (66 bytes)
adding [s] data/C.i (66 bytes)
adding [s] data/D.i (66 bytes)
adding [s] data/E.i (66 bytes)
adding [s] 00manifest.i (584 bytes)
adding [s] 00changelog.i (595 bytes)
adding [s] phaseroots (43 bytes)
adding [c] branch2-served (94 bytes)
adding [c] rbc-names-v1 (7 bytes)
adding [c] rbc-revs-v1 (40 bytes)
transferred 1.65 KB in * seconds (* */sec) (glob)
bundle2-input-part: total payload size 1840
bundle2-input-bundle: 1 parts total
updating the branch cache
finished applying clone bundle
query 1; heads
sending batch command
searching for changes
all remote heads known locally
no changes found
sending getbundle command
bundle2-input-bundle: with-transaction
bundle2-input-part: "listkeys" (params: 1 mandatory) supported
bundle2-input-part: "phase-heads" supported
bundle2-input-part: total payload size 24
bundle2-input-bundle: 2 parts total
checking for updated bookmarks
updating to branch default
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 000000000000, local: 000000000000+, remote: 9bc730a19041
A: remote created -> g
getting A
B: remote created -> g
getting B
C: remote created -> g
getting C
D: remote created -> g
getting D
E: remote created -> g
getting E
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
updating the branch cache
(sent 4 HTTP requests and * bytes; received * bytes in responses) (glob)
$ hg clone --stream http://localhost:$HGPORT streamv2-clone-explicit --debug
using http://localhost:$HGPORT/
sending capabilities command
sending clonebundles command
applying clone bundle from http://localhost:$HGPORT1/bundle.hg
bundle2-input-bundle: with-transaction
bundle2-input-part: "stream2" (params: 3 mandatory) supported
applying stream bundle
11 files to transfer, 1.65 KB of data
starting 4 threads for background file closing (?)
starting 4 threads for background file closing (?)
adding [s] data/A.i (66 bytes)
adding [s] data/B.i (66 bytes)
adding [s] data/C.i (66 bytes)
adding [s] data/D.i (66 bytes)
adding [s] data/E.i (66 bytes)
adding [s] 00manifest.i (584 bytes)
adding [s] 00changelog.i (595 bytes)
adding [s] phaseroots (43 bytes)
adding [c] branch2-served (94 bytes)
adding [c] rbc-names-v1 (7 bytes)
adding [c] rbc-revs-v1 (40 bytes)
transferred 1.65 KB in * seconds (* */sec) (glob)
bundle2-input-part: total payload size 1840
bundle2-input-bundle: 1 parts total
updating the branch cache
finished applying clone bundle
query 1; heads
sending batch command
searching for changes
all remote heads known locally
no changes found
sending getbundle command
bundle2-input-bundle: with-transaction
bundle2-input-part: "listkeys" (params: 1 mandatory) supported
bundle2-input-part: "phase-heads" supported
bundle2-input-part: total payload size 24
bundle2-input-bundle: 2 parts total
checking for updated bookmarks
updating to branch default
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 000000000000, local: 000000000000+, remote: 9bc730a19041
A: remote created -> g
getting A
B: remote created -> g
getting B
C: remote created -> g
getting C
D: remote created -> g
getting D
E: remote created -> g
getting E
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
updating the branch cache
(sent 4 HTTP requests and * bytes; received * bytes in responses) (glob)