Merge branch 'maint'
[gitweb.git] / builtin-checkout.c
index aec2bc6f8d71a41e9d1cb718a498bfea08b767c3..4497b7092d0e88aa731c64c0f22bf0d05ead0411 100644 (file)
@@ -43,7 +43,7 @@ static int post_checkout_hook(struct commit *old, struct commit *new,
 }
 
 static int update_some(const unsigned char *sha1, const char *base, int baselen,
-                      const char *pathname, unsigned mode, int stage)
+               const char *pathname, unsigned mode, int stage, void *context)
 {
        int len;
        struct cache_entry *ce;
@@ -67,7 +67,7 @@ static int update_some(const unsigned char *sha1, const char *base, int baselen,
 
 static int read_tree_some(struct tree *tree, const char **pathspec)
 {
-       read_tree_recursive(tree, "", 0, 0, pathspec, update_some);
+       read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
 
        /* update the index with the given tree's info
         * for all args, expanding wildcards, and exit
@@ -76,6 +76,15 @@ static int read_tree_some(struct tree *tree, const char **pathspec)
        return 0;
 }
 
+static int skip_same_name(struct cache_entry *ce, int pos)
+{
+       while (++pos < active_nr &&
+              !strcmp(active_cache[pos]->name, ce->name))
+               ; /* skip */
+       return pos;
+}
+
+
 static int checkout_paths(struct tree *source_tree, const char **pathspec)
 {
        int pos;
@@ -107,6 +116,20 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec)
        if (report_path_error(ps_matched, pathspec, 0))
                return 1;
 
+       /* Any unmerged paths? */
+       for (pos = 0; pos < active_nr; pos++) {
+               struct cache_entry *ce = active_cache[pos];
+               if (pathspec_match(pathspec, NULL, ce->name, 0)) {
+                       if (!ce_stage(ce))
+                               continue;
+                       errs = 1;
+                       error("path '%s' is unmerged", ce->name);
+                       pos = skip_same_name(ce, pos) - 1;
+               }
+       }
+       if (errs)
+               return 1;
+
        /* Now we are committed to check them out */
        memset(&state, 0, sizeof(state));
        state.force = 1;
@@ -114,7 +137,11 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec)
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
                if (pathspec_match(pathspec, NULL, ce->name, 0)) {
-                       errs |= checkout_entry(ce, &state, NULL);
+                       if (!ce_stage(ce)) {
+                               errs |= checkout_entry(ce, &state, NULL);
+                               continue;
+                       }
+                       pos = skip_same_name(ce, pos) - 1;
                }
        }
 
@@ -157,7 +184,7 @@ struct checkout_opts {
        int force;
        int writeout_error;
 
-       char *new_branch;
+       const char *new_branch;
        int new_branch_log;
        enum branch_track track;
 };
@@ -242,6 +269,8 @@ static int merge_working_tree(struct checkout_opts *opts,
                }
 
                /* 2-way merge to the new branch */
+               topts.initial_checkout = (!active_nr &&
+                                         (old->commit == new->commit));
                topts.update = 1;
                topts.merge = 1;
                topts.gently = opts->merge;
@@ -305,97 +334,15 @@ static int merge_working_tree(struct checkout_opts *opts,
        return 0;
 }
 
-static void report_tracking(struct branch_info *new, struct checkout_opts *opts)
+static void report_tracking(struct branch_info *new)
 {
-       /*
-        * We have switched to a new branch; is it building on
-        * top of another branch, and if so does that other branch
-        * have changes we do not have yet?
-        */
-       char *base;
-       unsigned char sha1[20];
-       struct commit *ours, *theirs;
-       char symmetric[84];
-       struct rev_info revs;
-       const char *rev_argv[10];
-       int rev_argc;
-       int num_ours, num_theirs;
-       const char *remote_msg;
+       struct strbuf sb = STRBUF_INIT;
        struct branch *branch = branch_get(new->name);
 
-       /*
-        * 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)
+       if (!format_tracking_info(branch, &sb))
                return;
-
-       /*
-        * 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);
-       ours = new->commit;
-       if (!hashcmp(sha1, ours->object.sha1))
-               return; /* we are the same */
-
-       /* 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++;
-       }
-
-       if (!prefixcmp(base, "refs/remotes/")) {
-               remote_msg = " remote";
-               base += strlen("refs/remotes/");
-       } 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);
+       fputs(sb.buf, stdout);
+       strbuf_release(&sb);
 }
 
 static void update_refs_for_switch(struct checkout_opts *opts,
@@ -441,7 +388,7 @@ static void update_refs_for_switch(struct checkout_opts *opts,
        remove_branch_state();
        strbuf_release(&msg);
        if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
-               report_tracking(new, opts);
+               report_tracking(new);
 }
 
 static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
@@ -468,13 +415,11 @@ static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
        }
 
        /*
-        * If the new thing isn't a branch and isn't HEAD and we're
-        * not starting a new branch, and we want messages, and we
-        * weren't on a branch, and we're moving to a new commit,
-        * describe the old commit.
+        * If we were on a detached HEAD, but we are now moving to
+        * a new commit, we want to mention the old commit once more
+        * to remind the user that it might be lost.
         */
-       if (!new->path && strcmp(new->name, "HEAD") && !opts->new_branch &&
-           !opts->quiet && !old.path && new->commit != old.commit)
+       if (!opts->quiet && !old.path && new->commit != old.commit)
                describe_detached_head("Previous HEAD position was", old.commit);
 
        if (!old.commit) {
@@ -512,21 +457,81 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                OPT_BOOLEAN('m', NULL, &opts.merge, "merge"),
                OPT_END(),
        };
+       int has_dash_dash;
 
        memset(&opts, 0, sizeof(opts));
        memset(&new, 0, sizeof(new));
 
        git_config(git_default_config, NULL);
 
-       opts.track = git_branch_track;
+       opts.track = BRANCH_TRACK_UNSPECIFIED;
 
        argc = parse_options(argc, argv, options, checkout_usage,
                             PARSE_OPT_KEEP_DASHDASH);
+
+       /* --track without -b should DWIM */
+       if (0 < opts.track && !opts.new_branch) {
+               const char *argv0 = argv[0];
+               if (!argc || !strcmp(argv0, "--"))
+                       die ("--track needs a branch name");
+               if (!prefixcmp(argv0, "refs/"))
+                       argv0 += 5;
+               if (!prefixcmp(argv0, "remotes/"))
+                       argv0 += 8;
+               argv0 = strchr(argv0, '/');
+               if (!argv0 || !argv0[1])
+                       die ("Missing branch name; try -b");
+               opts.new_branch = argv0 + 1;
+       }
+
+       if (opts.track == BRANCH_TRACK_UNSPECIFIED)
+               opts.track = git_branch_track;
+
+       if (opts.force && opts.merge)
+               die("git checkout: -f and -m are incompatible");
+
+       /*
+        * case 1: git checkout <ref> -- [<paths>]
+        *
+        *   <ref> must be a valid tree, everything after the '--' must be
+        *   a path.
+        *
+        * case 2: git checkout -- [<paths>]
+        *
+        *   everything after the '--' must be paths.
+        *
+        * 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.
+        *
+        *   Otherwise <something> shall not be ambiguous.
+        *   - If it's *only* a reference, treat it like case (1).
+        *   - If it's only a path, treat it like case (2).
+        *   - else: fail.
+        *
+        */
        if (argc) {
+               if (!strcmp(argv[0], "--")) {       /* case (2) */
+                       argv++;
+                       argc--;
+                       goto no_reference;
+               }
+
                arg = argv[0];
-               if (get_sha1(arg, rev))
-                       ;
-               else if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
+               has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
+
+               if (get_sha1(arg, rev)) {
+                       if (has_dash_dash)          /* case (1) */
+                               die("invalid reference: %s", arg);
+                       goto no_reference;          /* case (3 -> 2) */
+               }
+
+               /* we can't end up being in (2) anymore, eat the argument */
+               argv++;
+               argc--;
+
+               if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
                        new.name = arg;
                        setup_branch_path(&new);
                        if (resolve_ref(new.path, rev, 1, NULL))
@@ -535,25 +540,28 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                                new.path = NULL;
                        parse_commit(new.commit);
                        source_tree = new.commit->tree;
-                       argv++;
-                       argc--;
-               } else if ((source_tree = parse_tree_indirect(rev))) {
+               } else
+                       source_tree = parse_tree_indirect(rev);
+
+               if (!source_tree)                   /* case (1): want a tree */
+                       die("reference is not a tree: %s", arg);
+               if (!has_dash_dash) {/* case (3 -> 1) */
+                       /*
+                        * Do not complain the most common case
+                        *      git checkout branch
+                        * even if there happen to be a file called 'branch';
+                        * it would be extremely annoying.
+                        */
+                       if (argc)
+                               verify_non_filename(NULL, arg);
+               }
+               else {
                        argv++;
                        argc--;
                }
        }
 
-       if (argc && !strcmp(argv[0], "--")) {
-               argv++;
-               argc--;
-       }
-
-       if (!opts.new_branch && (opts.track != git_branch_track))
-               die("git checkout: --track and --no-track require -b");
-
-       if (opts.force && opts.merge)
-               die("git checkout: -f and -m are incompatible");
-
+no_reference:
        if (argc) {
                const char **pathspec = get_pathspec(prefix, argv);
 
@@ -572,6 +580,18 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                return checkout_paths(source_tree, pathspec);
        }
 
+       if (opts.new_branch) {
+               struct strbuf buf;
+               strbuf_init(&buf, 0);
+               strbuf_addstr(&buf, "refs/heads/");
+               strbuf_addstr(&buf, opts.new_branch);
+               if (!get_sha1(buf.buf, rev))
+                       die("git checkout: branch %s already exists", opts.new_branch);
+               if (check_ref_format(buf.buf))
+                       die("git checkout: we do not like '%s' as a branch name.", opts.new_branch);
+               strbuf_release(&buf);
+       }
+
        if (new.name && !new.commit) {
                die("Cannot switch branch to a non-commit.");
        }