push: allow already-exists advice to be disabled

Add 'advice.pushAlreadyExists' option to disable the advice shown when
an update is rejected for a reference that is not allowed to update at
all (verses those that are allowed to fast-forward.)

Signed-off-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: crorvick

Documentation/config.txt

@@ -142,8 +142,9 @@ advice.*::
 --
 	pushUpdateRejected::
 		Set this variable to 'false' if you want to disable
-		'pushNonFFCurrent', 'pushNonFFDefault', and
-		'pushNonFFMatching' simultaneously.
+		'pushNonFFCurrent', 'pushNonFFDefault',
+		'pushNonFFMatching', and 'pushAlreadyExists'
+		simultaneously.
 	pushNonFFCurrent::
 		Advice shown when linkgit:git-push[1] fails due to a
 		non-fast-forward update to the current branch.
@@ -158,6 +159,9 @@ advice.*::
 		'matching refs' explicitly (i.e. you used ':', or
 		specified a refspec that isn't your current branch) and
 		it resulted in a non-fast-forward error.
+	pushAlreadyExists::
+		Shown when linkgit:git-push[1] rejects an update that
+		does not qualify for fast-forwarding (e.g., a tag.)
 	statusHints::
 		Show directions on how to proceed from the current
 		state in the output of linkgit:git-status[1] and in

advice.c

@@ -4,6 +4,7 @@ int advice_push_update_rejected = 1;
 int advice_push_non_ff_current = 1;
 int advice_push_non_ff_default = 1;
 int advice_push_non_ff_matching = 1;
+int advice_push_already_exists = 1;
 int advice_status_hints = 1;
 int advice_commit_before_merge = 1;
 int advice_resolve_conflict = 1;
@@ -18,6 +19,7 @@ static struct {
 	{ "pushnonffcurrent", &advice_push_non_ff_current },
 	{ "pushnonffdefault", &advice_push_non_ff_default },
 	{ "pushnonffmatching", &advice_push_non_ff_matching },
+	{ "pushalreadyexists", &advice_push_already_exists },
 	{ "statushints", &advice_status_hints },
 	{ "commitbeforemerge", &advice_commit_before_merge },
 	{ "resolveconflict", &advice_resolve_conflict },

advice.h

@@ -7,6 +7,7 @@ extern int advice_push_update_rejected;
 extern int advice_push_non_ff_current;
 extern int advice_push_non_ff_default;
 extern int advice_push_non_ff_matching;
+extern int advice_push_already_exists;
 extern int advice_status_hints;
 extern int advice_commit_before_merge;
 extern int advice_resolve_conflict;

builtin/push.c

@@ -247,6 +247,8 @@ static void advise_checkout_pull_push(void)
 
 static void advise_ref_already_exists(void)
 {
+	if (!advice_push_already_exists || !advice_push_update_rejected)
+		return;
 	advise(_(message_advice_ref_already_exists));
 }