Merge branch 'jc/sha1-name-more'

Teaches the object name parser things like a "git describe" output
is always a commit object, "A" in "git log A" must be a committish,
and "A" and "B" in "git log A...B" both must be committish, etc., to
prolong the lifetime of abbreviated object names.

* jc/sha1-name-more: (27 commits)
  t1512: match the "other" object names
  t1512: ignore whitespaces in wc -l output
  rev-parse --disambiguate=<prefix>
  rev-parse: A and B in "rev-parse A..B" refer to committish
  reset: the command takes committish
  commit-tree: the command wants a tree and commits
  apply: --build-fake-ancestor expects blobs
  sha1_name.c: add support for disambiguating other types
  revision.c: the "log" family, except for "show", takes committish
  revision.c: allow handle_revision_arg() to take other flags
  sha1_name.c: introduce get_sha1_committish()
  sha1_name.c: teach lookup context to get_sha1_with_context()
  sha1_name.c: many short names can only be committish
  sha1_name.c: get_sha1_1() takes lookup flags
  sha1_name.c: get_describe_name() by definition groks only commits
  sha1_name.c: teach get_short_sha1() a commit-only option
  sha1_name.c: allow get_short_sha1() to take other flags
  get_sha1(): fix error status regression
  sha1_name.c: restructure disambiguation of short names
  sha1_name.c: correct misnamed "canonical" and "res"
  ...

Author: gitster

Documentation/git-rev-parse.txt

@@ -101,6 +101,12 @@ OPTIONS
 	The option core.warnAmbiguousRefs is used to select the strict
 	abbreviation mode.
 
+--disambiguate=<prefix>::
+	Show every object whose name begins with the given prefix.
+	The <prefix> must be at least 4 hexadecimal digits long to
+	avoid listing each and every object in the repository by
+	mistake.
+
 --all::
 	Show all refs found in `refs/`.
 

builtin/apply.c

@@ -3589,7 +3589,7 @@ static void build_fake_ancestor(struct patch *list, const char *filename)
 		name = patch->old_name ? patch->old_name : patch->new_name;
 		if (0 < patch->is_new)
 			continue;
-		else if (get_sha1(patch->old_sha1_prefix, sha1))
+		else if (get_sha1_blob(patch->old_sha1_prefix, sha1))
 			/* git diff has no index line for mode/type changes */
 			if (!patch->lines_added && !patch->lines_deleted) {
 				if (get_current_sha1(patch->old_name, sha1))

builtin/cat-file.c

@@ -91,7 +91,7 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
 	unsigned long size;
 	struct object_context obj_context;
 
-	if (get_sha1_with_context(obj_name, sha1, &obj_context))
+	if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
 		die("Not a valid object name %s", obj_name);
 
 	buf = NULL;

builtin/commit-tree.c

@@ -48,16 +48,16 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 	if (argc < 2 || !strcmp(argv[1], "-h"))
 		usage(commit_tree_usage);
 
-	if (get_sha1(argv[1], tree_sha1))
-		die("Not a valid object name %s", argv[1]);
+	if (get_sha1_tree(argv[1], tree_sha1))
+		die("Not a valid tree object name %s", argv[1]);
 
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
 		if (!strcmp(arg, "-p")) {
 			unsigned char sha1[20];
 			if (argc <= ++i)
 				usage(commit_tree_usage);
-			if (get_sha1(argv[i], sha1))
+			if (get_sha1_commit(argv[i], sha1))
 				die("Not a valid object name %s", argv[i]);
 			assert_sha1_type(sha1, OBJ_COMMIT);
 			new_parent(lookup_commit(sha1), &parents);
@@ -104,7 +104,7 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 			continue;
 		}
 
-		if (get_sha1(arg, tree_sha1))
+		if (get_sha1_tree(arg, tree_sha1))
 			die("Not a valid object name %s", arg);
 		if (got_tree)
 			die("Cannot give more than one trees");

builtin/log.c

@@ -367,6 +367,7 @@ int cmd_whatchanged(int argc, const char **argv, const char *prefix)
 	rev.simplify_history = 0;
 	memset(&opt, 0, sizeof(opt));
 	opt.def = "HEAD";
+	opt.revarg_opt = REVARG_COMMITTISH;
 	cmd_log_init(argc, argv, prefix, &rev, &opt);
 	if (!rev.diffopt.output_format)
 		rev.diffopt.output_format = DIFF_FORMAT_RAW;
@@ -557,6 +558,7 @@ int cmd_log(int argc, const char **argv, const char *prefix)
 	rev.always_show_header = 1;
 	memset(&opt, 0, sizeof(opt));
 	opt.def = "HEAD";
+	opt.revarg_opt = REVARG_COMMITTISH;
 	cmd_log_init(argc, argv, prefix, &rev, &opt);
 	return cmd_log_walk(&rev);
 }
@@ -1132,6 +1134,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 	rev.subject_prefix = fmt_patch_subject_prefix;
 	memset(&s_r_opt, 0, sizeof(s_r_opt));
 	s_r_opt.def = "HEAD";
+	s_r_opt.revarg_opt = REVARG_COMMITTISH;
 
 	if (default_attach) {
 		rev.mime_boundary = default_attach;

builtin/pack-objects.c

@@ -2373,7 +2373,7 @@ static void get_object_list(int ac, const char **av)
 			}
 			die("not a rev '%s'", line);
 		}
-		if (handle_revision_arg(line, &revs, flags, 1))
+		if (handle_revision_arg(line, &revs, flags, REVARG_CANNOT_BE_FILENAME))
 			die("bad revision '%s'", line);
 	}
 

builtin/reset.c

@@ -276,7 +276,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 		 * Otherwise, argv[i] could be either <rev> or <paths> and
 		 * has to be unambiguous.
 		 */
-		else if (!get_sha1(argv[i], sha1)) {
+		else if (!get_sha1_committish(argv[i], sha1)) {
 			/*
 			 * Ok, argv[i] looks like a rev; it should not
 			 * be a filename.
@@ -289,9 +289,15 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 		}
 	}
 
-	if (get_sha1(rev, sha1))
+	if (get_sha1_committish(rev, sha1))
 		die(_("Failed to resolve '%s' as a valid ref."), rev);
 
+	/*
+	 * NOTE: As "git reset $treeish -- $path" should be usable on
+	 * any tree-ish, this is not strictly correct. We are not
+	 * moving the HEAD to any commit; we are merely resetting the
+	 * entries in the index to that of a treeish.
+	 */
 	commit = lookup_commit_reference(sha1);
 	if (!commit)
 		die(_("Could not parse object '%s'."), rev);

builtin/rev-parse.c

@@ -195,6 +195,12 @@ static int anti_reference(const char *refname, const unsigned char *sha1, int fl
 	return 0;
 }
 
+static int show_abbrev(const unsigned char *sha1, void *cb_data)
+{
+	show_rev(NORMAL, sha1, NULL);
+	return 0;
+}
+
 static void show_datestring(const char *flag, const char *datestr)
 {
 	static char buffer[100];
@@ -238,7 +244,7 @@ static int try_difference(const char *arg)
 		next = "HEAD";
 	if (dotdot == arg)
 		this = "HEAD";
-	if (!get_sha1(this, sha1) && !get_sha1(next, end)) {
+	if (!get_sha1_committish(this, sha1) && !get_sha1_committish(next, end)) {
 		show_rev(NORMAL, end, next);
 		show_rev(symmetric ? NORMAL : REVERSED, sha1, this);
 		if (symmetric) {
@@ -278,7 +284,7 @@ static int try_parent_shorthands(const char *arg)
 		return 0;
 
 	*dotdot = 0;
-	if (get_sha1(arg, sha1))
+	if (get_sha1_committish(arg, sha1))
 		return 0;
 
 	if (!parents_only)
@@ -589,6 +595,10 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_ref(show_reference, NULL);
 				continue;
 			}
+			if (!prefixcmp(arg, "--disambiguate=")) {
+				for_each_abbrev(arg + 15, show_abbrev, NULL);
+				continue;
+			}
 			if (!strcmp(arg, "--bisect")) {
 				for_each_ref_in("refs/bisect/bad", show_reference, NULL);
 				for_each_ref_in("refs/bisect/good", anti_reference, NULL);

cache.h

@@ -790,17 +790,25 @@ struct object_context {
 	unsigned mode;
 };
 
+#define GET_SHA1_QUIETLY        01
+#define GET_SHA1_COMMIT         02
+#define GET_SHA1_COMMITTISH     04
+#define GET_SHA1_TREE          010
+#define GET_SHA1_TREEISH       020
+#define GET_SHA1_BLOB	       040
+#define GET_SHA1_ONLY_TO_DIE 04000
+
 extern int get_sha1(const char *str, unsigned char *sha1);
-extern int get_sha1_with_mode_1(const char *str, unsigned char *sha1, unsigned *mode, int only_to_die, const char *prefix);
-static inline int get_sha1_with_mode(const char *str, unsigned char *sha1, unsigned *mode)
-{
-	return get_sha1_with_mode_1(str, sha1, mode, 0, NULL);
-}
-extern int get_sha1_with_context_1(const char *name, unsigned char *sha1, struct object_context *orc, int only_to_die, const char *prefix);
-static inline int get_sha1_with_context(const char *str, unsigned char *sha1, struct object_context *orc)
-{
-	return get_sha1_with_context_1(str, sha1, orc, 0, NULL);
-}
+extern int get_sha1_commit(const char *str, unsigned char *sha1);
+extern int get_sha1_committish(const char *str, unsigned char *sha1);
+extern int get_sha1_tree(const char *str, unsigned char *sha1);
+extern int get_sha1_treeish(const char *str, unsigned char *sha1);
+extern int get_sha1_blob(const char *str, unsigned char *sha1);
+extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
+extern int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc);
+
+typedef int each_abbrev_fn(const unsigned char *sha1, void *);
+extern int for_each_abbrev(const char *prefix, each_abbrev_fn, void *);
 
 /*
  * Try to read a SHA1 in hexadecimal format from the 40 characters

commit.c

@@ -68,7 +68,7 @@ struct commit *lookup_commit_reference_by_name(const char *name)
 	unsigned char sha1[20];
 	struct commit *commit;
 
-	if (get_sha1(name, sha1))
+	if (get_sha1_committish(name, sha1))
 		return NULL;
 	commit = lookup_commit_reference(sha1);
 	if (!commit || parse_commit(commit))