directory-rename-detection.txt: technical docs on abilities and limitations

diff --git a/builtin/commit.c b/builtin/commit.c
index 092077c3eef7a81b3d814cee951cee98e37eac02..a842fea666a33bb2191d10cf452a255754bb44e6 100644 (file)
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -143,6 +143,16 @@ static int opt_parse_m(const struct option *opt, const char *arg, int unset)
        return 0;
 }
 
+static int opt_parse_rename_score(const struct option *opt, const char *arg, int unset)
+{
+       const char **value = opt->value;
+       if (arg != NULL && *arg == '=')
+               arg = arg + 1;
+
+       *value = arg;
+       return 0;
+}
+
 static void determine_whence(struct wt_status *s)
 {
        if (file_exists(git_path_merge_head()))
@@ -161,9 +171,9 @@ static void determine_whence(struct wt_status *s)
 static void status_init_config(struct wt_status *s, config_fn_t fn)
 {
        wt_status_prepare(s);
+       init_diff_ui_defaults();
        git_config(fn, s);
        determine_whence(s);
-       init_diff_ui_defaults();
        s->hints = advice_status_hints; /* must come after git_config() */
 }
 
@@ -218,8 +228,7 @@ static int list_paths(struct string_list *list, const char *with_tree,
 
        if (with_tree) {
                char *max_prefix = common_prefix(pattern);
-               overlay_tree_on_index(&the_index, with_tree,
-                                     max_prefix ? max_prefix : prefix);
+               overlay_tree_on_index(&the_index, with_tree, max_prefix);
                free(max_prefix);
        }
 
@@ -389,13 +398,9 @@ static const char *prepare_index(int argc, const char **argv, const char *prefix
                if (active_cache_changed
                    || !cache_tree_fully_valid(active_cache_tree))
                        update_main_cache_tree(WRITE_TREE_SILENT);
-               if (active_cache_changed) {
-                       if (write_locked_index(&the_index, &index_lock,
-                                              COMMIT_LOCK))
-                               die(_("unable to write new_index file"));
-               } else {
-                       rollback_lock_file(&index_lock);
-               }
+               if (write_locked_index(&the_index, &index_lock,
+                                      COMMIT_LOCK | SKIP_IF_UNCHANGED))
+                       die(_("unable to write new_index file"));
                commit_style = COMMIT_AS_IS;
                ret = get_index_file();
                goto out;
@@ -500,7 +505,7 @@ static int is_a_merge(const struct commit *current_head)
 static void assert_split_ident(struct ident_split *id, const struct strbuf *buf)
 {
        if (split_ident_line(id, buf->buf, buf->len) || !id->date_begin)
-               die("BUG: unable to parse our own ident: %s", buf->buf);
+               BUG("unable to parse our own ident: %s", buf->buf);
 }
 
 static void export_one(const char *var, const char *s, const char *e, int hack)
@@ -1264,11 +1269,31 @@ static int git_status_config(const char *k, const char *v, void *cb)
                        return error(_("Invalid untracked files mode '%s'"), v);
                return 0;
        }
+       if (!strcmp(k, "diff.renamelimit")) {
+               if (s->rename_limit == -1)
+                       s->rename_limit = git_config_int(k, v);
+               return 0;
+       }
+       if (!strcmp(k, "status.renamelimit")) {
+               s->rename_limit = git_config_int(k, v);
+               return 0;
+       }
+       if (!strcmp(k, "diff.renames")) {
+               if (s->detect_rename == -1)
+                       s->detect_rename = git_config_rename(k, v);
+               return 0;
+       }
+       if (!strcmp(k, "status.renames")) {
+               s->detect_rename = git_config_rename(k, v);
+               return 0;
+       }
        return git_diff_ui_config(k, v, NULL);
 }
 
 int cmd_status(int argc, const char **argv, const char *prefix)
 {
+       static int no_renames = -1;
+       static const char *rename_score_arg = (const char *)-1;
        static struct wt_status s;
        int fd;
        struct object_id oid;
@@ -1302,6 +1327,10 @@ int cmd_status(int argc, const char **argv, const char *prefix)
                  N_("ignore changes to submodules, optional when: all, dirty, untracked. (Default: all)"),
                  PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
                OPT_COLUMN(0, "column", &s.colopts, N_("list untracked files in columns")),
+               OPT_BOOL(0, "no-renames", &no_renames, N_("do not detect renames")),
+               { OPTION_CALLBACK, 'M', "find-renames", &rename_score_arg,
+                 N_("n"), N_("detect renames, optionally set similarity index"),
+                 PARSE_OPT_OPTARG, opt_parse_rename_score },
                OPT_END(),
        };
 
@@ -1341,6 +1370,14 @@ int cmd_status(int argc, const char **argv, const char *prefix)
        s.ignore_submodule_arg = ignore_submodule_arg;
        s.status_format = status_format;
        s.verbose = verbose;
+       if (no_renames != -1)
+               s.detect_rename = !no_renames;
+       if ((intptr_t)rename_score_arg != -1) {
+               if (s.detect_rename < DIFF_DETECT_RENAME)
+                       s.detect_rename = DIFF_DETECT_RENAME;
+               if (rename_score_arg)
+                       s.rename_score = parse_rename_score(&rename_score_arg);
+       }
 
        wt_status_collect(&s);