zsh_completion: declare appropriate local parameters for ->string form
When ->string form is used for _arguments, the function that calls it must
declare appropriate local parameters.
Managing local return value is needed to tell the completion system if our
function succeeded in suggesting something or not, plus without that `hg diff
-<TAB>` doesn't look right.
While at it, fix a copypaste error (s/diff_files/revert_files/).
Docs: http://zsh.sourceforge.net/Doc/Release/Completion-System.html
Differential Revision: https://phab.mercurial-scm.org/D4264
#require serve
$ cat <<EOF >> $HGRCPATH
> [extensions]
> schemes=
>
> [schemes]
> l = http://localhost:$HGPORT/
> parts = http://{1}:$HGPORT/
> z = file:\$PWD/
> EOF
$ hg init test
$ cd test
$ echo a > a
$ hg ci -Am initial
adding a
invalid scheme
$ hg log -R z:z
abort: no '://' in scheme url 'z:z'
[255]
http scheme
$ hg serve -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
$ cat hg.pid >> $DAEMON_PIDS
$ hg incoming l://
comparing with l://
searching for changes
no changes found
[1]
check that {1} syntax works
$ hg incoming --debug parts://localhost
using http://localhost:$HGPORT/
sending capabilities command
comparing with parts://localhost/
query 1; heads
sending batch command
searching for changes
all remote heads known locally
no changes found
[1]
check that paths are expanded
$ PWD=`pwd` hg incoming z://
comparing with z://
searching for changes
no changes found
[1]
check that debugexpandscheme outputs the canonical form
$ hg debugexpandscheme bb://user/repo
https://bitbucket.org/user/repo
expanding an unknown scheme emits the input
$ hg debugexpandscheme foobar://this/that
foobar://this/that
expanding a canonical URL emits the input
$ hg debugexpandscheme https://bitbucket.org/user/repo
https://bitbucket.org/user/repo
errors
$ cat errors.log
$ cd ..