DWIM "git checkout frotz" to "git checkout -b frotz origin/frotz"

diff --git a/revision.c b/revision.c
index d7d345bdd9c71eb0f8d77179b4af1b79049d054c..9fc4e8d3818f29261b1963f4995bc36f8af31179 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -133,7 +133,7 @@ void mark_parents_uninteresting(struct commit *commit)
 static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
 {
        if (revs->no_walk && (obj->flags & UNINTERESTING))
-               die("object ranges do not make sense when not walking revisions");
+               revs->no_walk = 0;
        if (revs->reflog_info && obj->type == OBJ_COMMIT &&
                        add_reflog_for_walk(revs->reflog_info,
                                (struct commit *)obj, name))
@@ -209,7 +209,7 @@ static struct commit *handle_commit(struct rev_info *revs, struct object *object
        }
 
        /*
-        * Tree object? Either mark it uniniteresting, or add it
+        * Tree object? Either mark it uninteresting, or add it
         * to the list of objects to look at later..
         */
        if (object->type == OBJ_TREE) {
@@ -256,10 +256,12 @@ static int everybody_uninteresting(struct commit_list *orig)
 
 /*
  * The goal is to get REV_TREE_NEW as the result only if the
- * diff consists of all '+' (and no other changes), and
- * REV_TREE_DIFFERENT otherwise (of course if the trees are
- * the same we want REV_TREE_SAME).  That means that once we
- * get to REV_TREE_DIFFERENT, we do not have to look any further.
+ * diff consists of all '+' (and no other changes), REV_TREE_OLD
+ * if the whole diff is removal of old data, and otherwise
+ * REV_TREE_DIFFERENT (of course if the trees are the same we
+ * want REV_TREE_SAME).
+ * That means that once we get to REV_TREE_DIFFERENT, we do not
+ * have to look any further.
  */
 static int tree_difference = REV_TREE_SAME;
 
@@ -268,22 +270,9 @@ static void file_add_remove(struct diff_options *options,
                    const unsigned char *sha1,
                    const char *fullpath)
 {
-       int diff = REV_TREE_DIFFERENT;
+       int diff = addremove == '+' ? REV_TREE_NEW : REV_TREE_OLD;
 
-       /*
-        * Is it an add of a new file? It means that the old tree
-        * didn't have it at all, so we will turn "REV_TREE_SAME" ->
-        * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
-        * (and if it already was "REV_TREE_NEW", we'll keep it
-        * "REV_TREE_NEW" of course).
-        */
-       if (addremove == '+') {
-               diff = tree_difference;
-               if (diff != REV_TREE_SAME)
-                       return;
-               diff = REV_TREE_NEW;
-       }
-       tree_difference = diff;
+       tree_difference |= diff;
        if (tree_difference == REV_TREE_DIFFERENT)
                DIFF_OPT_SET(options, HAS_CHANGES);
 }
@@ -305,6 +294,8 @@ static int rev_compare_tree(struct rev_info *revs, struct commit *parent, struct
 
        if (!t1)
                return REV_TREE_NEW;
+       if (!t2)
+               return REV_TREE_OLD;
 
        if (revs->simplify_by_decoration) {
                /*
@@ -323,8 +314,7 @@ static int rev_compare_tree(struct rev_info *revs, struct commit *parent, struct
                if (!revs->prune_data)
                        return REV_TREE_SAME;
        }
-       if (!t2)
-               return REV_TREE_DIFFERENT;
+
        tree_difference = REV_TREE_SAME;
        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
@@ -429,6 +419,7 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                                p->parents = NULL;
                        }
                /* fallthrough */
+               case REV_TREE_OLD:
                case REV_TREE_DIFFERENT:
                        tree_changed = 1;
                        pp = &parent->next;
@@ -1061,7 +1052,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
                revs->simplify_by_decoration = 1;
                revs->limited = 1;
                revs->prune = 1;
-               load_ref_decorations();
+               load_ref_decorations(DECORATE_SHORT_REFS);
        } else if (!strcmp(arg, "--date-order")) {
                revs->lifo = 0;
                revs->topo_order = 1;
@@ -1086,6 +1077,8 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
                revs->show_all = 1;
        } else if (!strcmp(arg, "--remove-empty")) {
                revs->remove_empty_trees = 1;
+       } else if (!strcmp(arg, "--merges")) {
+               revs->merges_only = 1;
        } else if (!strcmp(arg, "--no-merges")) {
                revs->no_merges = 1;
        } else if (!strcmp(arg, "--boundary")) {
@@ -1130,9 +1123,13 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
        } else if (!strcmp(arg, "--pretty")) {
                revs->verbose_header = 1;
                get_commit_format(arg+8, revs);
-       } else if (!prefixcmp(arg, "--pretty=")) {
+       } else if (!prefixcmp(arg, "--pretty=") || !prefixcmp(arg, "--format=")) {
                revs->verbose_header = 1;
                get_commit_format(arg+9, revs);
+       } else if (!strcmp(arg, "--oneline")) {
+               revs->verbose_header = 1;
+               get_commit_format("oneline", revs);
+               revs->abbrev_commit = 1;
        } else if (!strcmp(arg, "--graph")) {
                revs->topo_order = 1;
                revs->rewrite_parents = 1;
@@ -1162,8 +1159,10 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
                revs->simplify_history = 0;
        } else if (!strcmp(arg, "--relative-date")) {
                revs->date_mode = DATE_RELATIVE;
+               revs->date_mode_explicit = 1;
        } else if (!strncmp(arg, "--date=", 7)) {
                revs->date_mode = parse_date_format(arg + 7);
+               revs->date_mode_explicit = 1;
        } else if (!strcmp(arg, "--log-size")) {
                revs->show_log_size = 1;
        }
@@ -1667,7 +1666,7 @@ static inline int want_ancestry(struct rev_info *revs)
        return (revs->rewrite_parents || revs->children.name);
 }
 
-enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
+enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit)
 {
        if (commit->object.flags & SHOWN)
                return commit_ignore;
@@ -1681,6 +1680,8 @@ enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
                return commit_ignore;
        if (revs->no_merges && commit->parents && commit->parents->next)
                return commit_ignore;
+       if (revs->merges_only && !(commit->parents && commit->parents->next))
+               return commit_ignore;
        if (!commit_match(commit, revs))
                return commit_ignore;
        if (revs->prune && revs->dense) {
@@ -1693,12 +1694,23 @@ enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
                        if (!commit->parents || !commit->parents->next)
                                return commit_ignore;
                }
-               if (want_ancestry(revs) && rewrite_parents(revs, commit) < 0)
-                       return commit_error;
        }
        return commit_show;
 }
 
+enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
+{
+       enum commit_action action = get_commit_action(revs, commit);
+
+       if (action == commit_show &&
+           !revs->show_all &&
+           revs->prune && revs->dense && want_ancestry(revs)) {
+               if (rewrite_parents(revs, commit) < 0)
+                       return commit_error;
+       }
+       return action;
+}
+
 static struct commit *get_revision_1(struct rev_info *revs)
 {
        if (!revs->commits)