Merge branch 'js/branch-track'
[git/git.git] / builtin-checkout.c
index b1820a4..4a4bb8b 100644 (file)
@@ -205,8 +205,7 @@ static void setup_branch_path(struct branch_info *branch)
 }
 
 static int merge_working_tree(struct checkout_opts *opts,
-                             struct branch_info *old, struct branch_info *new,
-                             const char *prefix)
+                             struct branch_info *old, struct branch_info *new)
 {
        int ret;
        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
@@ -227,24 +226,25 @@ static int merge_working_tree(struct checkout_opts *opts,
                refresh_cache(REFRESH_QUIET);
 
                if (unmerged_cache()) {
-                       ret = opts->merge ? -1 :
-                               error("you need to resolve your current index first");
-               } else {
-                       topts.update = 1;
-                       topts.merge = 1;
-                       topts.gently = opts->merge;
-                       topts.fn = twoway_merge;
-                       topts.dir = xcalloc(1, sizeof(*topts.dir));
-                       topts.dir->show_ignored = 1;
-                       topts.dir->exclude_per_dir = ".gitignore";
-                       topts.prefix = prefix;
-                       tree = parse_tree_indirect(old->commit->object.sha1);
-                       init_tree_desc(&trees[0], tree->buffer, tree->size);
-                       tree = parse_tree_indirect(new->commit->object.sha1);
-                       init_tree_desc(&trees[1], tree->buffer, tree->size);
-                       ret = unpack_trees(2, trees, &topts);
+                       error("you need to resolve your current index first");
+                       return 1;
                }
-               if (ret) {
+
+               /* 2-way merge to the new branch */
+               topts.update = 1;
+               topts.merge = 1;
+               topts.gently = opts->merge;
+               topts.verbose_update = !opts->quiet;
+               topts.fn = twoway_merge;
+               topts.dir = xcalloc(1, sizeof(*topts.dir));
+               topts.dir->show_ignored = 1;
+               topts.dir->exclude_per_dir = ".gitignore";
+               tree = parse_tree_indirect(old->commit->object.sha1);
+               init_tree_desc(&trees[0], tree->buffer, tree->size);
+               tree = parse_tree_indirect(new->commit->object.sha1);
+               init_tree_desc(&trees[1], tree->buffer, tree->size);
+
+               if (unpack_trees(2, trees, &topts)) {
                        /*
                         * Unpack couldn't do a trivial merge; either
                         * give up or do a real merge, depending on
@@ -291,7 +291,7 @@ static int merge_working_tree(struct checkout_opts *opts,
        return 0;
 }
 
-static void adjust_to_tracking(struct branch_info *new, struct checkout_opts *opts)
+static void report_tracking(struct branch_info *new, struct checkout_opts *opts)
 {
        /*
         * We have switched to a new branch; is it building on
@@ -301,64 +301,88 @@ static void adjust_to_tracking(struct branch_info *new, struct checkout_opts *op
        char *base;
        unsigned char sha1[20];
        struct commit *ours, *theirs;
-       const char *msgfmt;
        char symmetric[84];
-       int show_log;
-       struct branch *branch = branch_get(NULL);
+       struct rev_info revs;
+       const char *rev_argv[10];
+       int rev_argc;
+       int num_ours, num_theirs;
+       const char *remote_msg;
+       struct branch *branch = branch_get(new->name);
 
-       if (!branch || !branch->merge)
+       /*
+        * Nothing to report unless we are marked to build on top of
+        * somebody else.
+        */
+       if (!branch || !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
                return;
 
-       base = branch->merge[0]->dst;
-
-       ours = new->commit;
-
-       sprintf(symmetric, "%s", sha1_to_hex(ours->object.sha1));
-
        /*
-        * Ok, it is tracking base; is it ahead of us?
+        * If what we used to build on no longer exists, there is
+        * nothing to report.
         */
+       base = branch->merge[0]->dst;
        if (!resolve_ref(base, sha1, 1, NULL))
                return;
-       theirs = lookup_commit(sha1);
-
-       sprintf(symmetric + 40, "...%s", sha1_to_hex(sha1));
 
+       theirs = lookup_commit(sha1);
+       ours = new->commit;
        if (!hashcmp(sha1, ours->object.sha1))
                return; /* we are the same */
 
-       show_log = 1;
-       if (in_merge_bases(theirs, &ours, 1)) {
-               msgfmt = "You are ahead of the tracked branch '%s'\n";
-               show_log = 0;
+       /* Run "rev-list --left-right ours...theirs" internally... */
+       rev_argc = 0;
+       rev_argv[rev_argc++] = NULL;
+       rev_argv[rev_argc++] = "--left-right";
+       rev_argv[rev_argc++] = symmetric;
+       rev_argv[rev_argc++] = "--";
+       rev_argv[rev_argc] = NULL;
+
+       strcpy(symmetric, sha1_to_hex(ours->object.sha1));
+       strcpy(symmetric + 40, "...");
+       strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
+
+       init_revisions(&revs, NULL);
+       setup_revisions(rev_argc, rev_argv, &revs, NULL);
+       prepare_revision_walk(&revs);
+
+       /* ... and count the commits on each side. */
+       num_ours = 0;
+       num_theirs = 0;
+       while (1) {
+               struct commit *c = get_revision(&revs);
+               if (!c)
+                       break;
+               if (c->object.flags & SYMMETRIC_LEFT)
+                       num_ours++;
+               else
+                       num_theirs++;
        }
-       else if (in_merge_bases(ours, &theirs, 1))
-               msgfmt = "Your branch can be fast-forwarded to the tracked branch '%s'\n";
-       else
-               msgfmt = "Both your branch and the tracked branch '%s' have own changes, you would eventually need to merge\n";
 
-       if (!prefixcmp(base, "refs/remotes/"))
+       if (!prefixcmp(base, "refs/remotes/")) {
+               remote_msg = " remote";
                base += strlen("refs/remotes/");
-       fprintf(stderr, msgfmt, base);
-
-       if (show_log) {
-               const char *args[32];
-               int ac;
-
-               ac = 0;
-               args[ac++] = "log";
-               args[ac++] = "--pretty=oneline";
-               args[ac++] = "--abbrev-commit";
-               args[ac++] = "--left-right";
-               args[ac++] = "--boundary";
-               args[ac++] = symmetric;
-               args[ac++] = "--";
-               args[ac] = NULL;
-
-               run_command_v_opt(args, RUN_GIT_CMD);
+       } else {
+               remote_msg = "";
        }
-}
 
+       if (!num_theirs)
+               printf("Your branch is ahead of the tracked%s branch '%s' "
+                      "by %d commit%s.\n",
+                      remote_msg, base,
+                      num_ours, (num_ours == 1) ? "" : "s");
+       else if (!num_ours)
+               printf("Your branch is behind the tracked%s branch '%s' "
+                      "by %d commit%s,\n"
+                      "and can be fast-forwarded.\n",
+                      remote_msg, base,
+                      num_theirs, (num_theirs == 1) ? "" : "s");
+       else
+               printf("Your branch and the tracked%s branch '%s' "
+                      "have diverged,\nand respectively "
+                      "have %d and %d different commit(s) each.\n",
+                      remote_msg, base,
+                      num_ours, num_theirs);
+}
 
 static void update_refs_for_switch(struct checkout_opts *opts,
                                   struct branch_info *old,
@@ -402,12 +426,11 @@ static void update_refs_for_switch(struct checkout_opts *opts,
        }
        remove_branch_state();
        strbuf_release(&msg);
-       if (new->path || !strcmp(new->name, "HEAD"))
-               adjust_to_tracking(new, opts);
+       if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
+               report_tracking(new, opts);
 }
 
-static int switch_branches(struct checkout_opts *opts,
-                          struct branch_info *new, const char *prefix)
+static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
 {
        int ret = 0;
        struct branch_info old;
@@ -448,7 +471,7 @@ static int switch_branches(struct checkout_opts *opts,
                opts->force = 1;
        }
 
-       ret = merge_working_tree(opts, &old, new, prefix);
+       ret = merge_working_tree(opts, &old, new);
        if (ret)
                return ret;
 
@@ -542,5 +565,5 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                die("Cannot switch branch to a non-commit.");
        }
 
-       return switch_branches(&opts, &new, prefix);
+       return switch_branches(&opts, &new);
 }