ZSH git add completion problems

[Gonzalo Peci]

There seem to be a problem when trying to autocomplete some git commands due to a bad prefix detection for "git ls-files".

If you check the new version of this package in the Arch repos, along with other updates you can find this file update:

> /usr/share/zsh/functions/Completion/Unix/_git
------
diff --git i/git.zsh w/git.zsh
index cf95bcd..745a57c 100644
--- i/git.zsh
+++ w/git.zsh
@@ -6625,7 +6625,7 @@ __git_files () {
   local pref=$gitcdup$gitprefix$PREFIX

   # First allow ls-files to pattern-match in case of remote repository
- files=(${(0)"$(_call_program files git ls-files -z --exclude-standard ${(q)opts} -- ${(q)${pref:+$pref\\\*}} 2>/dev/null)"})
+ files=(${(0)"$(_call_program files git ls-files -z --exclude-standard ${(q)opts} -- ${(q)${pref:+$pref\*}:-.} 2>/dev/null)"})
   __git_command_successful $pipestatus || return

   # If ls-files succeeded but returned nothing, try again with no pattern
------

If this is not applied, the command basically becomes:
> git ls-files -z --exclude-standard --others -- \'\'
when on the root of the git repository and fails with:
> fatal: empty string is not a valid pathspec. please use . instead if you meant to match all paths

This affects the "git add<tab>" command autocompletion and potentially others.

PS: This seems to be in "zsh-commons" but the report form did not allow me to select it