commit-graph: implement git-commit-graph write

Teach git-commit-graph to write graph files. Create new test script to verify
this command succeeds without failure.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index b466ecd..26b6360 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -1,9 +1,18 @@
 #include "builtin.h"
 #include "config.h"
+#include "dir.h"
+#include "lockfile.h"
 #include "parse-options.h"
+#include "commit-graph.h"
 
 static char const * const builtin_commit_graph_usage[] = {
 	N_("git commit-graph [--object-dir <objdir>]"),
+	N_("git commit-graph write [--object-dir <objdir>]"),
+	NULL
+};
+
+static const char * const builtin_commit_graph_write_usage[] = {
+	N_("git commit-graph write [--object-dir <objdir>]"),
 	NULL
 };
 
@@ -11,6 +20,25 @@ static struct opts_commit_graph {
 	const char *obj_dir;
 } opts;
 
+static int graph_write(int argc, const char **argv)
+{
+	static struct option builtin_commit_graph_write_options[] = {
+		OPT_STRING(0, "object-dir", &opts.obj_dir,
+			N_("dir"),
+			N_("The object directory to store the graph")),
+		OPT_END(),
+	};
+
+	argc = parse_options(argc, argv, NULL,
+			     builtin_commit_graph_write_options,
+			     builtin_commit_graph_write_usage, 0);
+
+	if (!opts.obj_dir)
+		opts.obj_dir = get_object_directory();
+
+	write_commit_graph(opts.obj_dir);
+	return 0;
+}
 
 int cmd_commit_graph(int argc, const char **argv, const char *prefix)
 {
@@ -31,6 +59,11 @@ int cmd_commit_graph(int argc, const char **argv, const char *prefix)
 			     builtin_commit_graph_usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
+	if (argc > 0) {
+		if (!strcmp(argv[0], "write"))
+			return graph_write(argc, argv);
+	}
+
 	usage_with_options(builtin_commit_graph_usage,
 			   builtin_commit_graph_options);
 }