largefiles: simplify iteration over standins
Instead of iterating over all files in the context and ignoring those
that are not standins, pass a standin-matcher to the context and
iterate over only the files matching.
Apart from making the intent clearer, this implementation will also
benefit from any future optimizations done to the manifest walking
code.
$ hg init
$ echo a > a
$ hg ci -Am0
adding a
$ hg -q clone . foo
$ touch .hg/store/journal
$ echo foo > a
$ hg ci -Am0
abort: abandoned transaction found!
(run 'hg recover' to clean up transaction)
[255]
$ hg recover
rolling back interrupted transaction
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
Check that zero-size journals are correctly aborted:
#if unix-permissions no-root
$ hg bundle -qa repo.hg
$ chmod -w foo/.hg/store/00changelog.i
$ hg -R foo unbundle repo.hg
adding changesets
abort: Permission denied: $TESTTMP/foo/.hg/store/.00changelog.i-* (glob)
[255]
$ if test -f foo/.hg/store/journal; then echo 'journal exists :-('; fi
#endif