builtin/describe.c: factor out describe_commit

Factor out describing commits into its own function `describe_commit`,
which will put any output to stdout into a strbuf, to be printed
afterwards.

As the next patch will teach Git to describe blobs using a commit and path,
this refactor will make it easy to reuse the code describing commits.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/describe.c b/builtin/describe.c
index 3136efde318b9b3eb319296b4650b437dd2d455e..9e9a5ed5d45669605576ceba906cb7a166e3d8d9 100644 (file)
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -256,7 +256,7 @@ static unsigned long finish_depth_computation(
        return seen_commits;
 }
 
-static void display_name(struct commit_name *n)
+static void append_name(struct commit_name *n, struct strbuf *dst)
 {
        if (n->prio == 2 && !n->tag) {
                n->tag = lookup_tag(&n->oid);
@@ -272,19 +272,18 @@ static void display_name(struct commit_name *n)
        }
 
        if (n->tag)
-               printf("%s", n->tag->tag);
+               strbuf_addstr(dst, n->tag->tag);
        else
-               printf("%s", n->path);
+               strbuf_addstr(dst, n->path);
 }
 
-static void show_suffix(int depth, const struct object_id *oid)
+static void append_suffix(int depth, const struct object_id *oid, struct strbuf *dst)
 {
-       printf("-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
+       strbuf_addf(dst, "-%d-g%s", depth, find_unique_abbrev(oid->hash, abbrev));
 }
 
-static void describe(const char *arg, int last_one)
+static void describe_commit(struct object_id *oid, struct strbuf *dst)
 {
-       struct object_id oid;
        struct commit *cmit, *gave_up_on = NULL;
        struct commit_list *list;
        struct commit_name *n;
@@ -293,26 +292,18 @@ static void describe(const char *arg, int last_one)
        unsigned long seen_commits = 0;
        unsigned int unannotated_cnt = 0;
 
-       if (debug)
-               fprintf(stderr, _("describe %s\n"), arg);
-
-       if (get_oid(arg, &oid))
-               die(_("Not a valid object name %s"), arg);
-       cmit = lookup_commit_reference(&oid);
-       if (!cmit)
-               die(_("%s is not a valid '%s' object"), arg, commit_type);
+       cmit = lookup_commit_reference(oid);
 
        n = find_commit_name(&cmit->object.oid);
        if (n && (tags || all || n->prio == 2)) {
                /*
                 * Exact match to an existing ref.
                 */
-               display_name(n);
+               append_name(n, dst);
                if (longformat)
-                       show_suffix(0, n->tag ? &n->tag->tagged->oid : &oid);
+                       append_suffix(0, n->tag ? &n->tag->tagged->oid : oid, dst);
                if (suffix)
-                       printf("%s", suffix);
-               printf("\n");
+                       strbuf_addstr(dst, suffix);
                return;
        }
 
@@ -386,10 +377,9 @@ static void describe(const char *arg, int last_one)
        if (!match_cnt) {
                struct object_id *cmit_oid = &cmit->object.oid;
                if (always) {
-                       printf("%s", find_unique_abbrev(cmit_oid->hash, abbrev));
+                       strbuf_addstr(dst, find_unique_abbrev(cmit_oid->hash, abbrev));
                        if (suffix)
-                               printf("%s", suffix);
-                       printf("\n");
+                               strbuf_addstr(dst, suffix);
                        return;
                }
                if (unannotated_cnt)
@@ -437,15 +427,36 @@ static void describe(const char *arg, int last_one)
                }
        }
 
-       display_name(all_matches[0].name);
+       append_name(all_matches[0].name, dst);
        if (abbrev)
-               show_suffix(all_matches[0].depth, &cmit->object.oid);
+               append_suffix(all_matches[0].depth, &cmit->object.oid, dst);
        if (suffix)
-               printf("%s", suffix);
-       printf("\n");
+               strbuf_addstr(dst, suffix);
+}
+
+static void describe(const char *arg, int last_one)
+{
+       struct object_id oid;
+       struct commit *cmit;
+       struct strbuf sb = STRBUF_INIT;
+
+       if (debug)
+               fprintf(stderr, _("describe %s\n"), arg);
+
+       if (get_oid(arg, &oid))
+               die(_("Not a valid object name %s"), arg);
+       cmit = lookup_commit_reference(&oid);
+       if (!cmit)
+               die(_("%s is not a valid '%s' object"), arg, commit_type);
+
+       describe_commit(&oid, &sb);
+
+       puts(sb.buf);
 
        if (!last_one)
                clear_commit_marks(cmit, -1);
+
+       strbuf_release(&sb);
 }
 
 int cmd_describe(int argc, const char **argv, const char *prefix)