diff options
-rw-r--r-- | builtin-checkout.c | 7 | ||||
-rw-r--r-- | cache.h | 1 | ||||
-rw-r--r-- | sha1_name.c | 42 | ||||
-rwxr-xr-x | t/t2012-checkout-last.sh | 27 |
4 files changed, 74 insertions, 3 deletions
diff --git a/builtin-checkout.c b/builtin-checkout.c index da04eed391..fe7c8584ca 100644 --- a/builtin-checkout.c +++ b/builtin-checkout.c @@ -689,7 +689,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) * case 3: git checkout <something> [<paths>] * * With no paths, if <something> is a commit, that is to - * switch to the branch or detach HEAD at it. + * switch to the branch or detach HEAD at it. As a special case, + * if <something> is A...B (missing A or B means HEAD but you can + * omit at most one side), and if there is a unique merge base + * between A and B, A...B names that merge base. * * With no paths, if <something> is _not_ a commit, no -t nor -b * was given, and there is a tracking branch whose name is @@ -715,7 +718,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) if (!strcmp(arg, "-")) arg = "@{-1}"; - if (get_sha1(arg, rev)) { + if (get_sha1_mb(arg, rev)) { if (has_dash_dash) /* case (1) */ die("invalid reference: %s", arg); if (!patch_mode && @@ -703,6 +703,7 @@ extern const char *resolve_ref(const char *path, unsigned char *sha1, int, int * extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref); extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref); extern int interpret_branch_name(const char *str, struct strbuf *); +extern int get_sha1_mb(const char *str, unsigned char *sha1); extern int refname_match(const char *abbrev_name, const char *full_name, const char **rules); extern const char *ref_rev_parse_rules[]; diff --git a/sha1_name.c b/sha1_name.c index 44bb62d270..d5a240cf07 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -794,6 +794,48 @@ release_return: return retval; } +int get_sha1_mb(const char *name, unsigned char *sha1) +{ + struct commit *one, *two; + struct commit_list *mbs; + unsigned char sha1_tmp[20]; + const char *dots; + int st; + + dots = strstr(name, "..."); + if (!dots) + return get_sha1(name, sha1); + if (dots == name) + st = get_sha1("HEAD", sha1_tmp); + else { + struct strbuf sb; + strbuf_init(&sb, dots - name); + strbuf_add(&sb, name, dots - name); + st = get_sha1(sb.buf, sha1_tmp); + strbuf_release(&sb); + } + if (st) + return st; + one = lookup_commit_reference_gently(sha1_tmp, 0); + if (!one) + return -1; + + if (get_sha1(dots[3] ? (dots + 3) : "HEAD", sha1_tmp)) + return -1; + two = lookup_commit_reference_gently(sha1_tmp, 0); + if (!two) + return -1; + mbs = get_merge_bases(one, two, 1); + if (!mbs || mbs->next) + st = -1; + else { + st = 0; + hashcpy(sha1, mbs->item->object.sha1); + } + free_commit_list(mbs); + return st; +} + /* * This is like "get_sha1_basic()", except it allows "sha1 expressions", * notably "xyz^" for "parent of xyz" diff --git a/t/t2012-checkout-last.sh b/t/t2012-checkout-last.sh index 87b30a268c..b44de9dc62 100755 --- a/t/t2012-checkout-last.sh +++ b/t/t2012-checkout-last.sh @@ -1,6 +1,6 @@ #!/bin/sh -test_description='checkout can switch to last branch' +test_description='checkout can switch to last branch and merge base' . ./test-lib.sh @@ -91,4 +91,29 @@ test_expect_success 'switch to twelfth from the last' ' test "z$(git symbolic-ref HEAD)" = "zrefs/heads/branch13" ' +test_expect_success 'merge base test setup' ' + git checkout -b another other && + echo "hello again" >>world && + git add world && + git commit -m third +' + +test_expect_success 'another...master' ' + git checkout another && + git checkout another...master && + test "z$(git rev-parse --verify HEAD)" = "z$(git rev-parse --verify master^)" +' + +test_expect_success '...master' ' + git checkout another && + git checkout ...master && + test "z$(git rev-parse --verify HEAD)" = "z$(git rev-parse --verify master^)" +' + +test_expect_success 'master...' ' + git checkout another && + git checkout master... && + test "z$(git rev-parse --verify HEAD)" = "z$(git rev-parse --verify master^)" +' + test_done |