merge-trees: let caller decide whether to renormalize

diff --git a/branch.c b/branch.c
index 05ef3f5c9ce6e1b55a7eb483a197fe9fd6e5437d..2ab42aaf4da38b4ea45ef7f0a0f6b807313d4a22 100644 (file)
--- a/branch.c
+++ b/branch.c
@@ -49,9 +49,19 @@ static int should_setup_rebase(const char *origin)
 
 void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
 {
+       const char *shortname = remote + 11;
+       int remote_is_branch = !prefixcmp(remote, "refs/heads/");
        struct strbuf key = STRBUF_INIT;
        int rebasing = should_setup_rebase(origin);
 
+       if (remote_is_branch
+           && !strcmp(local, shortname)
+           && !origin) {
+               warning("Not setting branch %s as its own upstream.",
+                       local);
+               return;
+       }
+
        strbuf_addf(&key, "branch.%s.remote", local);
        git_config_set(key.buf, origin ? origin : ".");
 
@@ -71,8 +81,8 @@ void install_branch_config(int flag, const char *local, const char *origin, cons
                strbuf_addstr(&key, origin ? "remote" : "local");
 
                /* Are we tracking a proper "branch"? */
-               if (!prefixcmp(remote, "refs/heads/")) {
-                       strbuf_addf(&key, " branch %s", remote + 11);
+               if (remote_is_branch) {
+                       strbuf_addf(&key, " branch %s", shortname);
                        if (origin)
                                strbuf_addf(&key, " from %s", origin);
                }
@@ -108,6 +118,7 @@ static int setup_tracking(const char *new_ref, const char *orig_ref,
                switch (track) {
                case BRANCH_TRACK_ALWAYS:
                case BRANCH_TRACK_EXPLICIT:
+               case BRANCH_TRACK_OVERRIDE:
                        break;
                default:
                        return 1;
@@ -128,18 +139,25 @@ void create_branch(const char *head,
                   const char *name, const char *start_name,
                   int force, int reflog, enum branch_track track)
 {
-       struct ref_lock *lock;
+       struct ref_lock *lock = NULL;
        struct commit *commit;
        unsigned char sha1[20];
        char *real_ref, msg[PATH_MAX + 20];
        struct strbuf ref = STRBUF_INIT;
        int forcing = 0;
+       int dont_change_ref = 0;
+       int explicit_tracking = 0;
+
+       if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
+               explicit_tracking = 1;
 
        if (strbuf_check_branch_ref(&ref, name))
                die("'%s' is not a valid branch name.", name);
 
        if (resolve_ref(ref.buf, sha1, 1, NULL)) {
-               if (!force)
+               if (!force && track == BRANCH_TRACK_OVERRIDE)
+                       dont_change_ref = 1;
+               else if (!force)
                        die("A branch named '%s' already exists.", name);
                else if (!is_bare_repository() && !strcmp(head, name))
                        die("Cannot force update the current branch.");
@@ -153,12 +171,12 @@ void create_branch(const char *head,
        switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
        case 0:
                /* Not branching from any existing branch */
-               if (track == BRANCH_TRACK_EXPLICIT)
+               if (explicit_tracking)
                        die("Cannot setup tracking information; starting point is not a branch.");
                break;
        case 1:
                /* Unique completion -- good, only if it is a real ref */
-               if (track == BRANCH_TRACK_EXPLICIT && !strcmp(real_ref, "HEAD"))
+               if (explicit_tracking && !strcmp(real_ref, "HEAD"))
                        die("Cannot setup tracking information; starting point is not a branch.");
                break;
        default:
@@ -170,25 +188,28 @@ void create_branch(const char *head,
                die("Not a valid branch point: '%s'.", start_name);
        hashcpy(sha1, commit->object.sha1);
 
-       lock = lock_any_ref_for_update(ref.buf, NULL, 0);
-       if (!lock)
-               die_errno("Failed to lock ref for update");
+       if (!dont_change_ref) {
+               lock = lock_any_ref_for_update(ref.buf, NULL, 0);
+               if (!lock)
+                       die_errno("Failed to lock ref for update");
+       }
 
        if (reflog)
                log_all_ref_updates = 1;
 
        if (forcing)
-               snprintf(msg, sizeof msg, "branch: Reset from %s",
+               snprintf(msg, sizeof msg, "branch: Reset to %s",
                         start_name);
-       else
+       else if (!dont_change_ref)
                snprintf(msg, sizeof msg, "branch: Created from %s",
                         start_name);
 
        if (real_ref && track)
                setup_tracking(name, real_ref, track);
 
-       if (write_ref_sha1(lock, sha1, msg) < 0)
-               die_errno("Failed to write ref");
+       if (!dont_change_ref)
+               if (write_ref_sha1(lock, sha1, msg) < 0)
+                       die_errno("Failed to write ref");
 
        strbuf_release(&ref);
        free(real_ref);