merge-tree: add -X strategy option

Add merge strategy option to produce more customizable merge result such
as automatically resolving conflicts.

Signed-off-by: Tang Yuyi <winglovet@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 0de42aecf4..7024b5ce2e 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -18,6 +18,7 @@
 #include "quote.h"
 #include "tree.h"
 #include "config.h"
+#include "strvec.h"
 
 static int line_termination = '\n';
 
@@ -414,6 +415,7 @@ struct merge_tree_options {
 	int show_messages;
 	int name_only;
 	int use_stdin;
+	struct merge_options merge_options;
 };
 
 static int real_merge(struct merge_tree_options *o,
@@ -423,7 +425,7 @@ static int real_merge(struct merge_tree_options *o,
 {
 	struct commit *parent1, *parent2;
 	struct commit_list *merge_bases = NULL;
-	struct merge_options opt;
+	struct merge_options opt = o->merge_options;
 	struct merge_result result = { 0 };
 	int show_messages = o->show_messages;
 
@@ -437,8 +439,6 @@ static int real_merge(struct merge_tree_options *o,
 		help_unknown_ref(branch2, "merge-tree",
 				 _("not something we can merge"));
 
-	init_merge_options(&opt, the_repository);
-
 	opt.show_rename_progress = 0;
 
 	opt.branch1 = branch1;
@@ -513,6 +513,7 @@ static int real_merge(struct merge_tree_options *o,
 int cmd_merge_tree(int argc, const char **argv, const char *prefix)
 {
 	struct merge_tree_options o = { .show_messages = -1 };
+	struct strvec xopts = STRVEC_INIT;
 	int expected_remaining_argc;
 	int original_argc;
 	const char *merge_base = NULL;
@@ -548,14 +549,25 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix)
 			   &merge_base,
 			   N_("commit"),
 			   N_("specify a merge-base for the merge")),
+		OPT_STRVEC('X', "strategy-option", &xopts, N_("option=value"),
+			N_("option for selected merge strategy")),
 		OPT_END()
 	};
 
+	/* Init merge options */
+	init_merge_options(&o.merge_options, the_repository);
+
 	/* Parse arguments */
 	original_argc = argc - 1; /* ignoring argv[0] */
 	argc = parse_options(argc, argv, prefix, mt_options,
 			     merge_tree_usage, PARSE_OPT_STOP_AT_NON_OPTION);
 
+	if (xopts.nr && o.mode == MODE_TRIVIAL)
+		die(_("--trivial-merge is incompatible with all other options"));
+	for (int x = 0; x < xopts.nr; x++)
+		if (parse_merge_opt(&o.merge_options, xopts.v[x]))
+			die(_("unknown strategy option: -X%s"), xopts.v[x]);
+
 	/* Handle --stdin */
 	if (o.use_stdin) {
 		struct strbuf buf = STRBUF_INIT;