[PATCH v3] contrib/completion: fix zsh completion regression from 59d85a2a05

[David Aguilar <davvid@gmail.com>]

A recent change to make git-completion.bash use $__git_cmd_idx
in more places broke a number of completions on zsh because it
modified __git_main but did not update __git_zsh_main.

Notably, completions for "add", "branch", "mv" and "push" were
broken as a result of this change.

In addition to the undefined variable usage, "git mv <tab>" also
prints the following error:

	__git_count_arguments:7: bad math expression:
	operand expected at `"1"'

	_git_mv:[:7: unknown condition: -gt

Remove the quotes around $__git_cmd_idx in __git_count_arguments
and set __git_cmd_idx=1 early in __git_zsh_main to fix the
regressions from 59d85a2a05.

Add "git" to the "words" array in _git_zsh_main to guarantee
that "git" is at least always in the completion list. It may not
be completely correct because __git_cmd_idx is not always 1,
but it is enough to fix the regression.

This was tested on zsh 5.7.1 (x86_64-apple-darwin19.0).

Helped-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: David Aguilar <davvid@gmail.com>
---
 contrib/completion/git-completion.bash | 2 +-
 contrib/completion/git-completion.zsh  | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 3c5739b905..b50c5d0ea3 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1306,7 +1306,7 @@ __git_count_arguments ()
 	local word i c=0
 
 	# Skip "git" (first argument)
-	for ((i="$__git_cmd_idx"; i < ${#words[@]}; i++)); do
+	for ((i=$__git_cmd_idx; i < ${#words[@]}; i++)); do
 		word="${words[i]}"
 
 		case "$word" in
diff --git a/contrib/completion/git-completion.zsh b/contrib/completion/git-completion.zsh
index 6c56296997..6405d7ba30 100644
--- a/contrib/completion/git-completion.zsh
+++ b/contrib/completion/git-completion.zsh
@@ -251,7 +251,7 @@ __git_zsh_main ()
 		done
 		;;
 	(arg)
-		local command="${words[1]}" __git_dir
+		local command="${words[1]}" __git_dir __git_cmd_idx=1
 
 		if (( $+opt_args[--bare] )); then
 			__git_dir='.'
@@ -261,7 +261,7 @@ __git_zsh_main ()
 
 		(( $+opt_args[--help] )) && command='help'
 
-		words=( ${orig_words[@]} )
+		words=( git ${orig_words[@]} )
 
 		__git_zsh_bash_func $command
 		;;
-- 
2.32.0.rc2.1.gf67de2b3ac