Teach @{-1} to git merge

1.6.2 will have @{-1} syntax advertised as "usable anywhere you can use
a branch name".  However, "git merge @{-1}" did not work.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-merge.c b/builtin-merge.c
index 885fad9bba1310e6ed8424f9d4b481e066760a9b..6d2160d0a3db1705d1372029dfa24752d453c8ec 100644 (file)
--- a/builtin-merge.c
+++ b/builtin-merge.c
@@ -356,9 +356,14 @@ static void merge_name(const char *remote, struct strbuf *msg)
        struct object *remote_head;
        unsigned char branch_head[20], buf_sha[20];
        struct strbuf buf = STRBUF_INIT;
+       struct strbuf bname = STRBUF_INIT;
        const char *ptr;
        int len, early;
 
+       len = strlen(remote);
+       if (interpret_nth_last_branch(remote, &bname) == len)
+               remote = bname.buf;
+
        memset(branch_head, 0, sizeof(branch_head));
        remote_head = peel_to_type(remote, 0, NULL, OBJ_COMMIT);
        if (!remote_head)
@@ -371,7 +376,7 @@ static void merge_name(const char *remote, struct strbuf *msg)
        if (!hashcmp(remote_head->sha1, branch_head)) {
                strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
                        sha1_to_hex(branch_head), remote);
-               return;
+               goto cleanup;
        }
 
        /* See if remote matches <name>^^^.. or <name>~<number> */
@@ -411,7 +416,8 @@ static void merge_name(const char *remote, struct strbuf *msg)
                                    sha1_to_hex(remote_head->sha1),
                                    truname.buf + 11,
                                    (early ? " (early part)" : ""));
-                       return;
+                       strbuf_release(&truname);
+                       goto cleanup;
                }
        }
 
@@ -432,10 +438,13 @@ static void merge_name(const char *remote, struct strbuf *msg)
                        strbuf_remove(&line, ptr-line.buf+1, 13);
                strbuf_addbuf(msg, &line);
                strbuf_release(&line);
-               return;
+               goto cleanup;
        }
        strbuf_addf(msg, "%s\t\tcommit '%s'\n",
                sha1_to_hex(remote_head->sha1), remote);
+cleanup:
+       strbuf_release(&buf);
+       strbuf_release(&bname);
 }
 
 static int git_merge_config(const char *k, const char *v, void *cb)

diff --git a/t/t0100-previous.sh b/t/t0100-previous.sh
index db51b421d6dc5370d847ea74433f3df196f225f8..315b9b3f10cfae0186afca6f8024d73cce0a19e2 100755 (executable)
--- a/t/t0100-previous.sh
+++ b/t/t0100-previous.sh
@@ -22,5 +22,28 @@ test_expect_success 'branch -d @{-12} when there is not enough switches yet' '
        git rev-parse --verify refs/heads/master
 '
 
+test_expect_success 'merge @{-1}' '
+       git checkout A &&
+       test_commit B &&
+       git checkout A &&
+       test_commit C &&
+       git branch -f master B &&
+       git branch -f other &&
+       git checkout other &&
+       git checkout master &&
+       git merge @{-1} &&
+       git cat-file commit HEAD | grep "Merge branch '\''other'\''"
+'
+
+test_expect_success 'merge @{-1} when there is not enough switches yet' '
+       git reflog expire --expire=now &&
+       git checkout -f master &&
+       git reset --hard B &&
+       git branch -f other C &&
+       git checkout other &&
+       git checkout master &&
+       test_must_fail git merge @{-12}
+'
+
 test_done