completion: suppress some -no- options

Most --no- options do have some use, even if rarely to negate some
option that's specified in an alias.

These options --no-ours and --no-theirs however have no clear
semantics. If I specify "--ours --no-theirs", the second will reset
writeout stage and is equivalent of "--no-ours --no-theirs" which is
not that easy to see. Drop them. You can either switch from --ours to
--theirs and back but you can never negate them.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/checkout.c

@@ -1119,10 +1119,12 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 		OPT_SET_INT('t', "track",  &opts.track, N_("set upstream info for new branch"),
 			BRANCH_TRACK_EXPLICIT),
 		OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
-		OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
-			    2),
-		OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
-			    3),
+		OPT_SET_INT_F('2', "ours", &opts.writeout_stage,
+			      N_("checkout our version for unmerged files"),
+			      2, PARSE_OPT_NONEG),
+		OPT_SET_INT_F('3', "theirs", &opts.writeout_stage,
+			      N_("checkout their version for unmerged files"),
+			      3, PARSE_OPT_NONEG),
 		OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)"),
 			   PARSE_OPT_NOCOMPLETE),
 		OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),

t/t9902-completion.sh

@@ -1245,9 +1245,7 @@ test_expect_success 'double dash "git checkout"' '
 	--orphan=Z
 	--no-orphan Z
 	--ours Z
-	--no-ours Z
 	--theirs Z
-	--no-theirs Z
 	--merge Z
 	--no-merge Z
 	--conflict=Z