push: rework the computation of fallbackheads to be correct
The previous computation tried to be smart but ended up being wrong. This was
caught by phase movement test while reworking the phase discovery logic to be
faster.
The previous logic was failing to catch case where the pushed set was not based
on a common heads (i.e. when the discovery seemed to have "over discovered"
content, outside the pushed set)
In the following graph, `e` is a common head and we `hg push -r f`. We need to
detect `c` as a fallback heads and we previous failed to do so::
e
|
d f
|/
c
|
b
|
a
The performance impact of the change seems minimal. On the most impacted
repository at hand (mozilla-try), the slowdown seems mostly mixed in the
overall noise `hg push` but seems to be in the hundred of milliseconds order of
magnitude. When using rust, we seems to be a bit faster, probably because we
leverage more accelaratd internals.
I added a couple of performance related common for further investigation later
on.
#require no-msys # MSYS will translate web paths as if they were file paths
This is a test of the push wire protocol over CGI-based hgweb.
initialize repository
$ hg init r
$ cd r
$ echo a > a
$ hg ci -A -m "0"
adding a
$ echo '[web]' > .hg/hgrc
$ echo 'allow_push = *' >> .hg/hgrc
$ echo 'push_ssl = false' >> .hg/hgrc
create hgweb invocation script
$ cat >hgweb.cgi <<HGWEB
> from mercurial import demandimport; demandimport.enable()
> from mercurial.hgweb import hgweb
> from mercurial.hgweb import wsgicgi
> application = hgweb(b'.', b'test repository')
> wsgicgi.launch(application)
> HGWEB
$ chmod 755 hgweb.cgi
test preparation
$ . "$TESTDIR/cgienv"
$ REQUEST_METHOD="POST"; export REQUEST_METHOD
$ CONTENT_TYPE="application/octet-stream"; export CONTENT_TYPE
$ hg bundle --type v1 --all bundle.hg
1 changesets found
$ CONTENT_LENGTH=279; export CONTENT_LENGTH;
expect failure because heads doesn't match (formerly known as 'unsynced changes')
$ QUERY_STRING="cmd=unbundle&heads=0000000000000000000000000000000000000000"; export QUERY_STRING
$ "$PYTHON" hgweb.cgi <bundle.hg >page1 2>&1
$ cat page1
Status: 200 Script output follows\r (esc)
Content-Type: application/mercurial-0.1\r (esc)
Content-Length: 64\r (esc)
\r (esc)
0
repository changed while preparing changes - please try again
successful force push
$ QUERY_STRING="cmd=unbundle&heads=666f726365"; export QUERY_STRING
$ "$PYTHON" hgweb.cgi <bundle.hg >page2 2>&1
$ cat page2
Status: 200 Script output follows\r (esc)
Content-Type: application/mercurial-0.1\r (esc)
Content-Length: 102\r (esc)
\r (esc)
1
adding changesets
adding manifests
adding file changes
added 0 changesets with 0 changes to 1 files
successful push, list of heads
$ QUERY_STRING="cmd=unbundle&heads=f7b1eb17ad24730a1651fccd46c43826d1bbc2ac"; export QUERY_STRING
$ "$PYTHON" hgweb.cgi <bundle.hg >page3 2>&1
$ cat page3
Status: 200 Script output follows\r (esc)
Content-Type: application/mercurial-0.1\r (esc)
Content-Length: 102\r (esc)
\r (esc)
1
adding changesets
adding manifests
adding file changes
added 0 changesets with 0 changes to 1 files
successful push, SHA1 hash of heads (unbundlehash capability)
$ QUERY_STRING="cmd=unbundle&heads=686173686564 5a785a5f9e0d433b88ed862b206b011b0c3a9d13"; export QUERY_STRING
$ "$PYTHON" hgweb.cgi <bundle.hg >page4 2>&1
$ cat page4
Status: 200 Script output follows\r (esc)
Content-Type: application/mercurial-0.1\r (esc)
Content-Length: 102\r (esc)
\r (esc)
1
adding changesets
adding manifests
adding file changes
added 0 changesets with 0 changes to 1 files
$ cd ..