bookmark: add a test for a race condition on push
Bookmark pointing to unknown nodes are ignored. Later these ignored bookmarks
are dropped when writing the file back on disk. On paper, this behavior should
be fine, but with the current implementation, it can lead to unexpected
bookmark deletions.
In theory, to make sure writer as a consistent view, taking the lock also
invalidate bookmark data we already loaded into memory. However this
invalidation is incomplete. The data are stored in a `filecache` that preserve
them if the bookmark related file are untouched. In practice, the bookmark data
in memory also depends of the changelog content, because of the step checking
if the bookmarks refers to a node known to the changelog. So if the bookmark
data were loaded from an up to date bookmark file but filtered with an outdated
changelog file this go undetected.
This condition is fairly specific, but can occurs very often in practice. We
introduce a test recreating the situation. The test comes in an independant
changeset to show it actually reproduce the situation. The fix will come soon
after.
A large share of the initial investigation of this race condition was made by
Valentin Gatien-Baron <valentin.gatienbaron@gmail.com>.
#require no-msys # MSYS will translate web paths as if they were file paths
This tests if CGI files from after d0db3462d568 but
before d74fc8dec2b4 still work.
$ hg init test
$ cat >hgweb.cgi <<HGWEB
> #!$PYTHON
> #
> # An example CGI script to use hgweb, edit as necessary
>
> import cgitb
> cgitb.enable()
>
> from mercurial import demandimport; demandimport.enable()
> from mercurial.hgweb import hgweb
> from mercurial.hgweb import wsgicgi
> from mercurial.hgweb.request import wsgiapplication
>
> def make_web_app():
> return hgweb(b"test", b"Empty test repository")
>
> wsgicgi.launch(wsgiapplication(make_web_app))
> HGWEB
$ chmod 755 hgweb.cgi
$ cat >hgweb.config <<HGWEBDIRCONF
> [paths]
> test = test
> HGWEBDIRCONF
$ cat >hgwebdir.cgi <<HGWEBDIR
> #!$PYTHON
> #
> # An example CGI script to export multiple hgweb repos, edit as necessary
>
> import cgitb
> cgitb.enable()
>
> from mercurial import demandimport; demandimport.enable()
> from mercurial.hgweb import hgwebdir
> from mercurial.hgweb import wsgicgi
> from mercurial.hgweb.request import wsgiapplication
>
> def make_web_app():
> return hgwebdir(b"hgweb.config")
>
> wsgicgi.launch(wsgiapplication(make_web_app))
> HGWEBDIR
$ chmod 755 hgwebdir.cgi
$ . "$TESTDIR/cgienv"
$ "$PYTHON" hgweb.cgi > page1
$ "$PYTHON" hgwebdir.cgi > page2
$ PATH_INFO="/test/"
$ PATH_TRANSLATED="/var/something/test.cgi"
$ REQUEST_URI="/test/test/"
$ SCRIPT_URI="http://hg.omnifarious.org/test/test/"
$ SCRIPT_URL="/test/test/"
$ "$PYTHON" hgwebdir.cgi > page3
$ grep -i error page1 page2 page3
[1]