hgweb: use patch.diffhunks in webutil.diffs to simplify the algorithm
Function patch.diffhunks yields items for a "block" (i.e. a file) as a whole
so take advantage of this to simplify the algorithm and avoid parsing diff
lines to determine whether we're starting a new "block" or not. Thus we drop
to external block counter and rely on diffhunks iterations instead.
We also take advantage of the fact that patch.diffhunks() yields *lines* of
hunks (instead of a string) to avoid building a list that is ''.join-ed into a
string that is then split.
As lines in 'header' returned by patch.diffhunks() have no trailing new line,
we need to insert it ourselves to match template expectations.
$ hg init
$ echo a > a
$ hg ci -qAm 'add a'
$ hg init subrepo
$ echo 'subrepo = http://example.net/libfoo' > .hgsub
$ hg ci -qAm 'added subrepo'
$ hg up -qC 0
$ echo ax > a
$ hg ci -m 'changed a'
created new head
$ hg up -qC 1
$ cd subrepo
$ echo b > b
$ hg add b
$ cd ..
Should fail, since there are added files to subrepo:
$ hg merge
abort: uncommitted changes in subrepository 'subrepo'
[255]