1 files changed, 70 insertions, 35 deletions

diff --git a/builtin/blame.c b/builtin/blame.c
index a7bd7a6fd8..f7aa95f4ba 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -658,8 +658,11 @@ static struct origin *find_rename(struct scoreboard *sb,
 /*
  * Append a new blame entry to a given output queue.
  */
-static void add_blame_entry(struct blame_entry ***queue, struct blame_entry *e)
+static void add_blame_entry(struct blame_entry ***queue,
+			    const struct blame_entry *src)
 {
+	struct blame_entry *e = xmalloc(sizeof(*e));
+	memcpy(e, src, sizeof(*e));
 	origin_incref(e->suspect);
 
 	e->next = **queue;
@@ -760,21 +763,15 @@ static void split_blame(struct blame_entry ***blamed,
 			struct blame_entry *split,
 			struct blame_entry *e)
 {
-	struct blame_entry *new_entry;
-
 	if (split[0].suspect && split[2].suspect) {
 		/* The first part (reuse storage for the existing entry e) */
 		dup_entry(unblamed, e, &split[0]);
 
 		/* The last part -- me */
-		new_entry = xmalloc(sizeof(*new_entry));
-		memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
-		add_blame_entry(unblamed, new_entry);
+		add_blame_entry(unblamed, &split[2]);
 
 		/* ... and the middle part -- parent */
-		new_entry = xmalloc(sizeof(*new_entry));
-		memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
-		add_blame_entry(blamed, new_entry);
+		add_blame_entry(blamed, &split[1]);
 	}
 	else if (!split[0].suspect && !split[2].suspect)
 		/*
@@ -785,18 +782,12 @@ static void split_blame(struct blame_entry ***blamed,
 	else if (split[0].suspect) {
 		/* me and then parent */
 		dup_entry(unblamed, e, &split[0]);
-
-		new_entry = xmalloc(sizeof(*new_entry));
-		memcpy(new_entry, &(split[1]), sizeof(struct blame_entry));
-		add_blame_entry(blamed, new_entry);
+		add_blame_entry(blamed, &split[1]);
 	}
 	else {
 		/* parent and then me */
 		dup_entry(blamed, e, &split[1]);
-
-		new_entry = xmalloc(sizeof(*new_entry));
-		memcpy(new_entry, &(split[2]), sizeof(struct blame_entry));
-		add_blame_entry(unblamed, new_entry);
+		add_blame_entry(unblamed, &split[2]);
 	}
 }
 
@@ -1700,13 +1691,23 @@ static void get_commit_info(struct commit *commit,
 }
 
 /*
+ * Write out any suspect information which depends on the path. This must be
+ * handled separately from emit_one_suspect_detail(), because a given commit
+ * may have changes in multiple paths. So this needs to appear each time
+ * we mention a new group.
+ *
  * To allow LF and other nonportable characters in pathnames,
  * they are c-style quoted as needed.
  */
-static void write_filename_info(const char *path)
+static void write_filename_info(struct origin *suspect)
 {
+	if (suspect->previous) {
+		struct origin *prev = suspect->previous;
+		printf("previous %s ", oid_to_hex(&prev->commit->object.oid));
+		write_name_quoted(prev->path, stdout, '\n');
+	}
 	printf("filename ");
-	write_name_quoted(path, stdout, '\n');
+	write_name_quoted(suspect->path, stdout, '\n');
 }
 
 /*
@@ -1735,11 +1736,6 @@ static int emit_one_suspect_detail(struct origin *suspect, int repeat)
 	printf("summary %s\n", ci.summary.buf);
 	if (suspect->commit->object.flags & UNINTERESTING)
 		printf("boundary\n");
-	if (suspect->previous) {
-		struct origin *prev = suspect->previous;
-		printf("previous %s ", oid_to_hex(&prev->commit->object.oid));
-		write_name_quoted(prev->path, stdout, '\n');
-	}
 
 	commit_info_destroy(&ci);
 
@@ -1760,7 +1756,7 @@ static void found_guilty_entry(struct blame_entry *ent,
 		       oid_to_hex(&suspect->commit->object.oid),
 		       ent->s_lno + 1, ent->lno + 1, ent->num_lines);
 		emit_one_suspect_detail(suspect, 0);
-		write_filename_info(suspect->path);
+		write_filename_info(suspect);
 		maybe_flush_or_die(stdout, "stdout");
 	}
 	pi->blamed_lines += ent->num_lines;
@@ -1884,7 +1880,7 @@ static void emit_porcelain_details(struct origin *suspect, int repeat)
 {
 	if (emit_one_suspect_detail(suspect, repeat) ||
 	    (suspect->commit->object.flags & MORE_THAN_ONE_PATH))
-		write_filename_info(suspect->path);
+		write_filename_info(suspect);
 }
 
 static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
@@ -1896,7 +1892,7 @@ static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
 	struct origin *suspect = ent->suspect;
 	char hex[GIT_SHA1_HEXSZ + 1];
 
-	sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
+	oid_to_hex_r(hex, &suspect->commit->object.oid);
 	printf("%s %d %d %d\n",
 	       hex,
 	       ent->s_lno + 1,
@@ -1936,7 +1932,7 @@ static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
 	int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
 
 	get_commit_info(suspect->commit, &ci, 1);
-	sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
+	oid_to_hex_r(hex, &suspect->commit->object.oid);
 
 	cp = nth_line(sb, ent->lno);
 	for (cnt = 0; cnt < ent->num_lines; cnt++) {
@@ -2111,7 +2107,7 @@ static void find_alignment(struct scoreboard *sb, int *option)
 	unsigned largest_score = 0;
 	struct blame_entry *e;
 	int compute_auto_abbrev = (abbrev < 0);
-	int auto_abbrev = default_abbrev;
+	int auto_abbrev = DEFAULT_ABBREV;
 
 	for (e = sb->ent; e; e = e->next) {
 		struct origin *suspect = e->suspect;
@@ -2456,6 +2452,41 @@ static char *prepare_final(struct scoreboard *sb)
 	return xstrdup_or_null(name);
 }
 
+static const char *dwim_reverse_initial(struct scoreboard *sb)
+{
+	/*
+	 * DWIM "git blame --reverse ONE -- PATH" as
+	 * "git blame --reverse ONE..HEAD -- PATH" but only do so
+	 * when it makes sense.
+	 */
+	struct object *obj;
+	struct commit *head_commit;
+	unsigned char head_sha1[20];
+
+	if (sb->revs->pending.nr != 1)
+		return NULL;
+
+	/* Is that sole rev a committish? */
+	obj = sb->revs->pending.objects[0].item;
+	obj = deref_tag(obj, NULL, 0);
+	if (obj->type != OBJ_COMMIT)
+		return NULL;
+
+	/* Do we have HEAD? */
+	if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_sha1, NULL))
+		return NULL;
+	head_commit = lookup_commit_reference_gently(head_sha1, 1);
+	if (!head_commit)
+		return NULL;
+
+	/* Turn "ONE" into "ONE..HEAD" then */
+	obj->flags |= UNINTERESTING;
+	add_pending_object(sb->revs, &head_commit->object, "HEAD");
+
+	sb->final = (struct commit *)obj;
+	return sb->revs->pending.objects[0].name;
+}
+
 static char *prepare_initial(struct scoreboard *sb)
 {
 	int i;
@@ -2474,14 +2505,17 @@ static char *prepare_initial(struct scoreboard *sb)
 		if (obj->type != OBJ_COMMIT)
 			die("Non commit %s?", revs->pending.objects[i].name);
 		if (sb->final)
-			die("More than one commit to dig down to %s and %s?",
+			die("More than one commit to dig up from, %s and %s?",
 			    revs->pending.objects[i].name,
 			    final_commit_name);
 		sb->final = (struct commit *) obj;
 		final_commit_name = revs->pending.objects[i].name;
 	}
+
+	if (!final_commit_name)
+		final_commit_name = dwim_reverse_initial(sb);
 	if (!final_commit_name)
-		die("No commit to dig down to?");
+		die("No commit to dig up from?");
 	return xstrdup(final_commit_name);
 }
 
@@ -2558,8 +2592,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 		 * and are only included here to get included in the "-h"
 		 * output:
 		 */
-		{ OPTION_LOWLEVEL_CALLBACK, 0, "indent-heuristic", NULL, NULL, N_("Use an experimental indent-based heuristic to improve diffs"), PARSE_OPT_NOARG, parse_opt_unknown_cb },
-		{ OPTION_LOWLEVEL_CALLBACK, 0, "compaction-heuristic", NULL, NULL, N_("Use an experimental blank-line-based heuristic to improve diffs"), PARSE_OPT_NOARG, parse_opt_unknown_cb },
+		{ OPTION_LOWLEVEL_CALLBACK, 0, "indent-heuristic", NULL, NULL, N_("Use an experimental heuristic to improve diffs"), PARSE_OPT_NOARG, parse_opt_unknown_cb },
 
 		OPT_BIT(0, "minimal", &xdl_opts, N_("Spend extra cycles to find better match"), XDF_NEED_MINIMAL),
 		OPT_STRING('S', NULL, &revs_file, N_("file"), N_("Use revisions from <file> instead of calling git-rev-list")),
@@ -2607,7 +2640,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 	}
 parse_done:
 	no_whole_file_rename = !DIFF_OPT_TST(&revs.diffopt, FOLLOW_RENAMES);
-	xdl_opts |= revs.diffopt.xdl_opts & (XDF_COMPACTION_HEURISTIC | XDF_INDENT_HEURISTIC);
+	xdl_opts |= revs.diffopt.xdl_opts & XDF_INDENT_HEURISTIC;
 	DIFF_OPT_CLR(&revs.diffopt, FOLLOW_RENAMES);
 	argc = parse_options_end(&ctx);
 
@@ -2618,9 +2651,11 @@ parse_done:
 	} else if (show_progress < 0)
 		show_progress = isatty(2);
 
-	if (0 < abbrev)
+	if (0 < abbrev && abbrev < GIT_SHA1_HEXSZ)
 		/* one more abbrev length is needed for the boundary commit */
 		abbrev++;
+	else if (!abbrev)
+		abbrev = GIT_SHA1_HEXSZ;
 
 	if (revs_file && read_ancestry(revs_file))
 		die_errno("reading graft file '%s' failed", revs_file);