log: decorate HEAD with branch name under --decorate=full, too

diff --git a/log-tree.c b/log-tree.c
index 7f0890e4ac14348e78f7f1e305629fa745a79392..92259bcb0a56f5ed0febd24369b5cf54dfe9e0fb 100644 (file)
--- a/log-tree.c
+++ b/log-tree.c
@@ -13,6 +13,8 @@
 #include "line-log.h"
 
 static struct decoration name_decoration = { "object names" };
+static int decoration_loaded;
+static int decoration_flags;
 
 static char decoration_colors[][COLOR_MAXLEN] = {
        GIT_COLOR_RESET,
@@ -146,9 +148,9 @@ static int add_graft_decoration(const struct commit_graft *graft, void *cb_data)
 
 void load_ref_decorations(int flags)
 {
-       static int loaded;
-       if (!loaded) {
-               loaded = 1;
+       if (!decoration_loaded) {
+               decoration_loaded = 1;
+               decoration_flags = flags;
                for_each_ref(add_ref_decoration, &flags);
                head_ref(add_ref_decoration, &flags);
                for_each_commit_graft(add_graft_decoration, NULL);
@@ -172,6 +174,54 @@ static void show_children(struct rev_info *opt, struct commit *commit, int abbre
        }
 }
 
+/*
+ * Do we have HEAD in the output, and also the branch it points at?
+ * If so, find that decoration entry for that current branch.
+ */
+static const struct name_decoration *current_pointed_by_HEAD(const struct name_decoration *decoration)
+{
+       const struct name_decoration *list, *head = NULL;
+       const char *branch_name = NULL;
+       unsigned char unused[20];
+       int rru_flags;
+
+       /* First find HEAD */
+       for (list = decoration; list; list = list->next)
+               if (list->type == DECORATION_REF_HEAD) {
+                       head = list;
+                       break;
+               }
+       if (!head)
+               return NULL;
+
+       /* Now resolve and find the matching current branch */
+       branch_name = resolve_ref_unsafe("HEAD", 0, unused, &rru_flags);
+       if (!(rru_flags & REF_ISSYMREF))
+               return NULL;
+
+       if ((decoration_flags == DECORATE_SHORT_REFS)) {
+               if (!skip_prefix(branch_name, "refs/heads/", &branch_name))
+                       return NULL;
+       } else {
+               /*
+                * Each decoration has a refname in full; keep
+                * branch_name also in full, but still make sure
+                * HEAD is a reasonable ref.
+                */
+               if (!starts_with(branch_name, "refs/"))
+                       return NULL;
+       }
+
+       /* OK, do we have that ref in the list? */
+       for (list = decoration; list; list = list->next)
+               if ((list->type == DECORATION_REF_LOCAL) &&
+                   !strcmp(branch_name, list->name)) {
+                       return list;
+               }
+
+       return NULL;
+}
+
 /*
  * The caller makes sure there is no funny color before calling.
  * format_decorations_extended makes sure the same after return.
@@ -184,6 +234,7 @@ void format_decorations_extended(struct strbuf *sb,
                        const char *suffix)
 {
        const struct name_decoration *decoration;
+       const struct name_decoration *current_and_HEAD;
        const char *color_commit =
                diff_get_color(use_color, DIFF_COMMIT);
        const char *color_reset =
@@ -192,15 +243,37 @@ void format_decorations_extended(struct strbuf *sb,
        decoration = get_name_decoration(&commit->object);
        if (!decoration)
                return;
+
+       current_and_HEAD = current_pointed_by_HEAD(decoration);
        while (decoration) {
-               strbuf_addstr(sb, color_commit);
-               strbuf_addstr(sb, prefix);
-               strbuf_addstr(sb, decorate_get_color(use_color, decoration->type));
-               if (decoration->type == DECORATION_REF_TAG)
-                       strbuf_addstr(sb, "tag: ");
-               strbuf_addstr(sb, decoration->name);
-               strbuf_addstr(sb, color_reset);
-               prefix = separator;
+               /*
+                * When both current and HEAD are there, only
+                * show HEAD->current where HEAD would have
+                * appeared, skipping the entry for current.
+                */
+               if (decoration != current_and_HEAD) {
+                       strbuf_addstr(sb, color_commit);
+                       strbuf_addstr(sb, prefix);
+                       strbuf_addstr(sb, color_reset);
+                       strbuf_addstr(sb, decorate_get_color(use_color, decoration->type));
+                       if (decoration->type == DECORATION_REF_TAG)
+                               strbuf_addstr(sb, "tag: ");
+
+                       strbuf_addstr(sb, decoration->name);
+
+                       if (current_and_HEAD &&
+                           decoration->type == DECORATION_REF_HEAD) {
+                               strbuf_addstr(sb, color_reset);
+                               strbuf_addstr(sb, color_commit);
+                               strbuf_addstr(sb, " -> ");
+                               strbuf_addstr(sb, color_reset);
+                               strbuf_addstr(sb, decorate_get_color(use_color, current_and_HEAD->type));
+                               strbuf_addstr(sb, current_and_HEAD->name);
+                       }
+                       strbuf_addstr(sb, color_reset);
+
+                       prefix = separator;
+               }
                decoration = decoration->next;
        }
        strbuf_addstr(sb, color_commit);