zsh completion: disable defaults and verbose output when completing
If ui.verbose is set to True in hgrc, commands used to provide completions
would yield bad results. For example, qpush completion would include the
patch numbers and statuses as returned by qunapplied -v, instead of just
the patch names.
Defaults are also disabled when completing to prevent similar issues when
an option is set that changes a command's output.
-- With aaa
Status:
A somename
other-file
Diff:
diff --git a/other-file b/somename
copy from other-file
copy to somename
-- With zzz
Status:
A somename
other-file
Diff:
diff --git a/other-file b/somename
copy from other-file
copy to somename