1 files changed, 173 insertions, 75 deletions

diff --git a/builtin-describe.c b/builtin-describe.c
index 669110cb06..71be2a9364 100644
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -4,21 +4,39 @@
 #include "refs.h"
 #include "builtin.h"
 #include "exec_cmd.h"
+#include "parse-options.h"
+#include "diff.h"
 
 #define SEEN		(1u<<0)
 #define MAX_TAGS	(FLAG_BITS - 1)
 
-static const char describe_usage[] =
-"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
+static const char * const describe_usage[] = {
+	"git describe [options] <committish>*",
+	"git describe [options] --dirty",
+	NULL
+};
 
 static int debug;	/* Display lots of verbose info */
-static int all;	/* Default to annotated tags only */
-static int tags;	/* But allow any tags if --tags is specified */
+static int all;	/* Any valid ref can be used */
+static int tags;	/* Allow lightweight tags */
+static int longformat;
 static int abbrev = DEFAULT_ABBREV;
 static int max_candidates = 10;
+static int found_names;
+static const char *pattern;
+static int always;
+static const char *dirty;
+
+/* diff-index command arguments to check if working tree is dirty. */
+static const char *diff_index_args[] = {
+	"diff-index", "--quiet", "HEAD", "--", NULL
+};
+
 
 struct commit_name {
+	struct tag *tag;
 	int prio; /* annotated tag = 2, tag = 1, head = 0 */
+	unsigned char sha1[20];
 	char path[FLEX_ARRAY]; /* more */
 };
 static const char *prio_names[] = {
@@ -27,37 +45,59 @@ static const char *prio_names[] = {
 
 static void add_to_known_names(const char *path,
 			       struct commit *commit,
-			       int prio)
+			       int prio,
+			       const unsigned char *sha1)
 {
 	struct commit_name *e = commit->util;
 	if (!e || e->prio < prio) {
 		size_t len = strlen(path)+1;
 		free(e);
 		e = xmalloc(sizeof(struct commit_name) + len);
+		e->tag = NULL;
 		e->prio = prio;
+		hashcpy(e->sha1, sha1);
 		memcpy(e->path, path, len);
 		commit->util = e;
 	}
+	found_names = 1;
 }
 
 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 {
-	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+	int might_be_tag = !prefixcmp(path, "refs/tags/");
+	struct commit *commit;
 	struct object *object;
-	int prio;
+	unsigned char peeled[20];
+	int is_tag, prio;
 
-	if (!commit)
+	if (!all && !might_be_tag)
 		return 0;
-	object = parse_object(sha1);
+
+	if (!peel_ref(path, peeled) && !is_null_sha1(peeled)) {
+		commit = lookup_commit_reference_gently(peeled, 1);
+		if (!commit)
+			return 0;
+		is_tag = !!hashcmp(sha1, commit->object.sha1);
+	} else {
+		commit = lookup_commit_reference_gently(sha1, 1);
+		object = parse_object(sha1);
+		if (!commit || !object)
+			return 0;
+		is_tag = object->type == OBJ_TAG;
+	}
+
 	/* If --all, then any refs are used.
 	 * If --tags, then any tags are used.
 	 * Otherwise only annotated tags are used.
 	 */
-	if (!prefixcmp(path, "refs/tags/")) {
-		if (object->type == OBJ_TAG)
+	if (might_be_tag) {
+		if (is_tag)
 			prio = 2;
 		else
 			prio = 1;
+
+		if (pattern && fnmatch(pattern, path + 10, 0))
+			prio = 0;
 	}
 	else
 		prio = 0;
@@ -65,10 +105,8 @@ static int get_name(const char *path, const unsigned char *sha1, int flag, void
 	if (!all) {
 		if (!prio)
 			return 0;
-		if (!tags && prio < 2)
-			return 0;
 	}
-	add_to_known_names(all ? path + 5 : path + 10, commit, prio);
+	add_to_known_names(all ? path + 5 : path + 10, commit, prio, sha1);
 	return 0;
 }
 
@@ -83,8 +121,6 @@ static int compare_pt(const void *a_, const void *b_)
 {
 	struct possible_tag *a = (struct possible_tag *)a_;
 	struct possible_tag *b = (struct possible_tag *)b_;
-	if (a->name->prio != b->name->prio)
-		return b->name->prio - a->name->prio;
 	if (a->depth != b->depth)
 		return a->depth - b->depth;
 	if (a->found_order != b->found_order)
@@ -125,16 +161,37 @@ static unsigned long finish_depth_computation(
 	return seen_commits;
 }
 
+static void display_name(struct commit_name *n)
+{
+	if (n->prio == 2 && !n->tag) {
+		n->tag = lookup_tag(n->sha1);
+		if (!n->tag || parse_tag(n->tag) || !n->tag->tag)
+			die("annotated tag %s not available", n->path);
+		if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
+			warning("tag '%s' is really '%s' here", n->tag->tag, n->path);
+	}
+
+	if (n->tag)
+		printf("%s", n->tag->tag);
+	else
+		printf("%s", n->path);
+}
+
+static void show_suffix(int depth, const unsigned char *sha1)
+{
+	printf("-%d-g%s", depth, find_unique_abbrev(sha1, abbrev));
+}
+
 static void describe(const char *arg, int last_one)
 {
 	unsigned char sha1[20];
 	struct commit *cmit, *gave_up_on = NULL;
 	struct commit_list *list;
-	static int initialized = 0;
 	struct commit_name *n;
 	struct possible_tag all_matches[MAX_TAGS];
 	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 	unsigned long seen_commits = 0;
+	unsigned int unannotated_cnt = 0;
 
 	if (get_sha1(arg, sha1))
 		die("Not a valid object name %s", arg);
@@ -142,17 +199,22 @@ static void describe(const char *arg, int last_one)
 	if (!cmit)
 		die("%s is not a valid '%s' object", arg, commit_type);
 
-	if (!initialized) {
-		initialized = 1;
-		for_each_ref(get_name, NULL);
-	}
-
 	n = cmit->util;
-	if (n) {
-		printf("%s\n", n->path);
+	if (n && (tags || all || n->prio == 2)) {
+		/*
+		 * Exact match to an existing ref.
+		 */
+		display_name(n);
+		if (longformat)
+			show_suffix(0, n->tag ? n->tag->tagged->sha1 : sha1);
+		if (dirty)
+			printf("%s", dirty);
+		printf("\n");
 		return;
 	}
 
+	if (!max_candidates)
+		die("no tag exactly matches '%s'", sha1_to_hex(cmit->object.sha1));
 	if (debug)
 		fprintf(stderr, "searching to describe %s\n", arg);
 
@@ -165,7 +227,9 @@ static void describe(const char *arg, int last_one)
 		seen_commits++;
 		n = c->util;
 		if (n) {
-			if (match_cnt < max_candidates) {
+			if (!tags && !all && n->prio < 2) {
+				unannotated_cnt++;
+			} else if (match_cnt < max_candidates) {
 				struct possible_tag *t = &all_matches[match_cnt++];
 				t->name = n;
 				t->depth = seen_commits - 1;
@@ -201,8 +265,24 @@ static void describe(const char *arg, int last_one)
 		}
 	}
 
-	if (!match_cnt)
-		die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
+	if (!match_cnt) {
+		const unsigned char *sha1 = cmit->object.sha1;
+		if (always) {
+			printf("%s", find_unique_abbrev(sha1, abbrev));
+			if (dirty)
+				printf("%s", dirty);
+			printf("\n");
+			return;
+		}
+		if (unannotated_cnt)
+			die("No annotated tags can describe '%s'.\n"
+			    "However, there were unannotated tags: try --tags.",
+			    sha1_to_hex(sha1));
+		else
+			die("No tags can describe '%s'.\n"
+			    "Try --always, or create some tags.",
+			    sha1_to_hex(sha1));
+	}
 
 	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
 
@@ -229,12 +309,13 @@ static void describe(const char *arg, int last_one)
 				sha1_to_hex(gave_up_on->object.sha1));
 		}
 	}
-	if (abbrev == 0)
-		printf("%s\n", all_matches[0].name->path );
-	else
-		printf("%s-%d-g%s\n", all_matches[0].name->path,
-		       all_matches[0].depth,
-		       find_unique_abbrev(cmit->object.sha1, abbrev));
+
+	display_name(all_matches[0].name);
+	if (abbrev)
+		show_suffix(all_matches[0].depth, cmit->object.sha1);
+	if (dirty)
+		printf("%s", dirty);
+	printf("\n");
 
 	if (!last_one)
 		clear_commit_marks(cmit, -1);
@@ -242,57 +323,74 @@ static void describe(const char *arg, int last_one)
 
 int cmd_describe(int argc, const char **argv, const char *prefix)
 {
-	int i;
 	int contains = 0;
+	struct option options[] = {
+		OPT_BOOLEAN(0, "contains",   &contains, "find the tag that comes after the commit"),
+		OPT_BOOLEAN(0, "debug",      &debug, "debug search strategy on stderr"),
+		OPT_BOOLEAN(0, "all",        &all, "use any ref in .git/refs"),
+		OPT_BOOLEAN(0, "tags",       &tags, "use any tag in .git/refs/tags"),
+		OPT_BOOLEAN(0, "long",       &longformat, "always use long format"),
+		OPT__ABBREV(&abbrev),
+		OPT_SET_INT(0, "exact-match", &max_candidates,
+			    "only output exact matches", 0),
+		OPT_INTEGER(0, "candidates", &max_candidates,
+			    "consider <n> most recent tags (default: 10)"),
+		OPT_STRING(0, "match",       &pattern, "pattern",
+			   "only consider tags matching <pattern>"),
+		OPT_BOOLEAN(0, "always",     &always,
+			   "show abbreviated commit object as fallback"),
+		{OPTION_STRING, 0, "dirty",  &dirty, "mark",
+			   "append <mark> on dirty working tree (default: \"-dirty\")",
+		 PARSE_OPT_OPTARG, NULL, (intptr_t) "-dirty"},
+		OPT_END(),
+	};
 
-	for (i = 1; i < argc; i++) {
-		const char *arg = argv[i];
-
-		if (*arg != '-')
-			break;
-		else if (!strcmp(arg, "--contains"))
-			contains = 1;
-		else if (!strcmp(arg, "--debug"))
-			debug = 1;
-		else if (!strcmp(arg, "--all"))
-			all = 1;
-		else if (!strcmp(arg, "--tags"))
-			tags = 1;
-		else if (!prefixcmp(arg, "--abbrev=")) {
-			abbrev = strtoul(arg + 9, NULL, 10);
-			if (abbrev != 0 && (abbrev < MINIMUM_ABBREV || 40 < abbrev))
-				abbrev = DEFAULT_ABBREV;
-		}
-		else if (!prefixcmp(arg, "--candidates=")) {
-			max_candidates = strtoul(arg + 13, NULL, 10);
-			if (max_candidates < 1)
-				max_candidates = 1;
-			else if (max_candidates > MAX_TAGS)
-				max_candidates = MAX_TAGS;
-		}
-		else
-			usage(describe_usage);
-	}
+	argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
+	if (max_candidates < 0)
+		max_candidates = 0;
+	else if (max_candidates > MAX_TAGS)
+		max_candidates = MAX_TAGS;
 
 	save_commit_buffer = 0;
 
+	if (longformat && abbrev == 0)
+		die("--long is incompatible with --abbrev=0");
+
 	if (contains) {
-		const char **args = xmalloc((4 + argc - i) * sizeof(char*));
-		args[0] = "name-rev";
-		args[1] = "--name-only";
-		args[2] = "--tags";
-		memcpy(args + 3, argv + i, (argc - i) * sizeof(char*));
-		args[3 + argc - i] = NULL;
-		return cmd_name_rev(3 + argc - i, args, prefix);
+		const char **args = xmalloc((7 + argc) * sizeof(char *));
+		int i = 0;
+		args[i++] = "name-rev";
+		args[i++] = "--name-only";
+		args[i++] = "--no-undefined";
+		if (always)
+			args[i++] = "--always";
+		if (!all) {
+			args[i++] = "--tags";
+			if (pattern) {
+				char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1);
+				sprintf(s, "--refs=refs/tags/%s", pattern);
+				args[i++] = s;
+			}
+		}
+		memcpy(args + i, argv, argc * sizeof(char *));
+		args[i + argc] = NULL;
+		return cmd_name_rev(i + argc, args, prefix);
 	}
 
-	if (argc <= i)
+	for_each_ref(get_name, NULL);
+	if (!found_names && !always)
+		die("No names found, cannot describe anything.");
+
+	if (argc == 0) {
+		if (dirty && !cmd_diff_index(ARRAY_SIZE(diff_index_args) - 1, diff_index_args, prefix))
+			dirty = NULL;
 		describe("HEAD", 1);
-	else
-		while (i < argc) {
-			describe(argv[i], (i == argc - 1));
-			i++;
+	} else if (dirty) {
+		die("--dirty is incompatible with committishes");
+	} else {
+		while (argc-- > 0) {
+			describe(*argv++, argc == 0);
 		}
-
+	}
 	return 0;
 }