From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 3 Apr 2013 16:34:53 +0000 (-0700)
Subject: Merge branch 'jc/sha1-name-object-peeler'
X-Git-Tag: v1.8.3-rc0~118
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/1b7b22bfd0fb1fe62cf9d40e2b1de031cc48771d?hp=-c

Merge branch 'jc/sha1-name-object-peeler'

There was no good way to ask "I have a random string that came from
outside world. I want to turn it into a 40-hex object name while
making sure such an object exists".  A new peeling suffix ^{object}
can be used for that purpose, together with "rev-parse --verify".

* jc/sha1-name-object-peeler:
peel_onion(): teach $foo^{object} peeler
peel_onion: disambiguate to favor tree-ish when we know we want a tree-ish
---

1b7b22bfd0fb1fe62cf9d40e2b1de031cc48771d
diff --combined Documentation/revisions.txt
index 314e25da73,e82a4db61c..1707d451b6
--- a/Documentation/revisions.txt
+++ b/Documentation/revisions.txt
@@@ -23,7 -23,7 +23,7 @@@ blobs contained in a commit
    A symbolic ref name.  E.g. 'master' typically means the commit
    object referenced by 'refs/heads/master'.  If you
    happen to have both 'heads/master' and 'tags/master', you can
 -  explicitly say 'heads/master' to tell git which one you mean.
 +  explicitly say 'heads/master' to tell Git which one you mean.
    When ambiguous, a '<refname>' is disambiguated by taking the
    first match in the following rules:
  
@@@ -116,6 -116,11 +116,11 @@@ some output processing may assume ref n
    object of that type is found or the object cannot be
    dereferenced anymore (in which case, barf).  '<rev>{caret}0'
    is a short-hand for '<rev>{caret}\{commit\}'.
+ +
+ 'rev{caret}\{object\}' can be used to make sure 'rev' names an
+ object that exists, without requiring 'rev' to be a tag, and
+ without dereferencing 'rev'; because a tag is already an object,
+ it does not have to be dereferenced even once to get to an object.
  
  '<rev>{caret}\{\}', e.g. 'v0.99.8{caret}\{\}'::
    A suffix '{caret}' followed by an empty brace pair
diff --combined sha1_name.c
index 2fbda48e02,85b6e75741..3820f28ae7
--- a/sha1_name.c
+++ b/sha1_name.c
@@@ -594,7 -594,7 +594,7 @@@ struct object *peel_to_type(const char 
  	while (1) {
  		if (!o || (!o->parsed && !parse_object(o->sha1)))
  			return NULL;
- 		if (o->type == expected_type)
+ 		if (expected_type == OBJ_ANY || o->type == expected_type)
  			return o;
  		if (o->type == OBJ_TAG)
  			o = ((struct tag*) o)->tagged;
@@@ -645,6 -645,8 +645,8 @@@ static int peel_onion(const char *name
  		expected_type = OBJ_TREE;
  	else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
  		expected_type = OBJ_BLOB;
+ 	else if (!prefixcmp(sp, "object}"))
+ 		expected_type = OBJ_ANY;
  	else if (sp[0] == '}')
  		expected_type = OBJ_NONE;
  	else if (sp[0] == '/')
@@@ -654,6 -656,8 +656,8 @@@
  
  	if (expected_type == OBJ_COMMIT)
  		lookup_flags = GET_SHA1_COMMITTISH;
+ 	else if (expected_type == OBJ_TREE)
+ 		lookup_flags = GET_SHA1_TREEISH;
  
  	if (get_sha1_1(name, sp - name - 2, outer, lookup_flags))
  		return -1;
@@@ -856,8 -860,8 +860,8 @@@ static int get_sha1_oneline(const char 
  }
  
  struct grab_nth_branch_switch_cbdata {
 -	long cnt, alloc;
 -	struct strbuf *buf;
 +	int remaining;
 +	struct strbuf buf;
  };
  
  static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
@@@ -867,6 -871,7 +871,6 @@@
  	struct grab_nth_branch_switch_cbdata *cb = cb_data;
  	const char *match = NULL, *target = NULL;
  	size_t len;
 -	int nth;
  
  	if (!prefixcmp(message, "checkout: moving from ")) {
  		match = message + strlen("checkout: moving from ");
@@@ -875,12 -880,11 +879,12 @@@
  
  	if (!match || !target)
  		return 0;
 -
 -	len = target - match;
 -	nth = cb->cnt++ % cb->alloc;
 -	strbuf_reset(&cb->buf[nth]);
 -	strbuf_add(&cb->buf[nth], match, len);
 +	if (--(cb->remaining) == 0) {
 +		len = target - match;
 +		strbuf_reset(&cb->buf);
 +		strbuf_add(&cb->buf, match, len);
 +		return 1; /* we are done */
 +	}
  	return 0;
  }
  
@@@ -891,7 -895,7 +895,7 @@@
  static int interpret_nth_prior_checkout(const char *name, struct strbuf *buf)
  {
  	long nth;
 -	int i, retval;
 +	int retval;
  	struct grab_nth_branch_switch_cbdata cb;
  	const char *brace;
  	char *num_end;
@@@ -901,22 -905,34 +905,22 @@@
  	brace = strchr(name, '}');
  	if (!brace)
  		return -1;
 -	nth = strtol(name+3, &num_end, 10);
 +	nth = strtol(name + 3, &num_end, 10);
  	if (num_end != brace)
  		return -1;
  	if (nth <= 0)
  		return -1;
 -	cb.alloc = nth;
 -	cb.buf = xmalloc(nth * sizeof(struct strbuf));
 -	for (i = 0; i < nth; i++)
 -		strbuf_init(&cb.buf[i], 20);
 -	cb.cnt = 0;
 +	cb.remaining = nth;
 +	strbuf_init(&cb.buf, 20);
 +
  	retval = 0;
 -	for_each_recent_reflog_ent("HEAD", grab_nth_branch_switch, 40960, &cb);
 -	if (cb.cnt < nth) {
 -		cb.cnt = 0;
 -		for_each_reflog_ent("HEAD", grab_nth_branch_switch, &cb);
 -	}
 -	if (cb.cnt < nth)
 -		goto release_return;
 -	i = cb.cnt % nth;
 -	strbuf_reset(buf);
 -	strbuf_add(buf, cb.buf[i].buf, cb.buf[i].len);
 -	retval = brace-name+1;
 -
 -release_return:
 -	for (i = 0; i < nth; i++)
 -		strbuf_release(&cb.buf[i]);
 -	free(cb.buf);
 +	if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
 +		strbuf_reset(buf);
 +		strbuf_add(buf, cb.buf.buf, cb.buf.len);
 +		retval = brace - name + 1;
 +	}
  
 +	strbuf_release(&cb.buf);
  	return retval;
  }