From: Junio C Hamano <gitster@pobox.com>
Date: Sat, 23 Jan 2010 00:08:13 +0000 (-0800)
Subject: Merge branch 'js/refer-upstream'
X-Git-Tag: v1.7.0-rc0~20
X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=4ca1b623865a9dc100f95a7867e35a9f73d7507a;p=git.git

Merge branch 'js/refer-upstream'

* js/refer-upstream:
  Teach @{upstream} syntax to strbuf_branchanme()
  t1506: more test for @{upstream} syntax
  Introduce <branch>@{upstream} notation
---

4ca1b623865a9dc100f95a7867e35a9f73d7507a
diff --cc sha1_name.c
index 1739e9e61,2376c6d8f..9215ad1d0
--- a/sha1_name.c
+++ b/sha1_name.c
@@@ -794,48 -805,60 +805,102 @@@ release_return
  	return retval;
  }
  
 +int get_sha1_mb(const char *name, unsigned char *sha1)
 +{
 +	struct commit *one, *two;
 +	struct commit_list *mbs;
 +	unsigned char sha1_tmp[20];
 +	const char *dots;
 +	int st;
 +
 +	dots = strstr(name, "...");
 +	if (!dots)
 +		return get_sha1(name, sha1);
 +	if (dots == name)
 +		st = get_sha1("HEAD", sha1_tmp);
 +	else {
 +		struct strbuf sb;
 +		strbuf_init(&sb, dots - name);
 +		strbuf_add(&sb, name, dots - name);
 +		st = get_sha1(sb.buf, sha1_tmp);
 +		strbuf_release(&sb);
 +	}
 +	if (st)
 +		return st;
 +	one = lookup_commit_reference_gently(sha1_tmp, 0);
 +	if (!one)
 +		return -1;
 +
 +	if (get_sha1(dots[3] ? (dots + 3) : "HEAD", sha1_tmp))
 +		return -1;
 +	two = lookup_commit_reference_gently(sha1_tmp, 0);
 +	if (!two)
 +		return -1;
 +	mbs = get_merge_bases(one, two, 1);
 +	if (!mbs || mbs->next)
 +		st = -1;
 +	else {
 +		st = 0;
 +		hashcpy(sha1, mbs->item->object.sha1);
 +	}
 +	free_commit_list(mbs);
 +	return st;
 +}
 +
+ /*
+  * This reads short-hand syntax that not only evaluates to a commit
+  * object name, but also can act as if the end user spelled the name
+  * of the branch from the command line.
+  *
+  * - "@{-N}" finds the name of the Nth previous branch we were on, and
+  *   places the name of the branch in the given buf and returns the
+  *   number of characters parsed if successful.
+  *
+  * - "<branch>@{upstream}" finds the name of the other ref that
+  *   <branch> is configured to merge with (missing <branch> defaults
+  *   to the current branch), and places the name of the branch in the
+  *   given buf and returns the number of characters parsed if
+  *   successful.
+  *
+  * If the input is not of the accepted format, it returns a negative
+  * number to signal an error.
+  *
+  * If the input was ok but there are not N branch switches in the
+  * reflog, it returns 0.
+  */
+ int interpret_branch_name(const char *name, struct strbuf *buf)
+ {
+ 	char *cp;
+ 	struct branch *upstream;
+ 	int namelen = strlen(name);
+ 	int len = interpret_nth_prior_checkout(name, buf);
+ 	int tmp_len;
+ 
+ 	if (!len)
+ 		return len; /* syntax Ok, not enough switches */
+ 	if (0 < len)
+ 		return len; /* consumed from the front */
+ 	cp = strchr(name, '@');
+ 	if (!cp)
+ 		return -1;
+ 	tmp_len = upstream_mark(cp, namelen - (cp - name));
+ 	if (!tmp_len)
+ 		return -1;
+ 	len = cp + tmp_len - name;
+ 	cp = xstrndup(name, cp - name);
+ 	upstream = branch_get(*cp ? cp : NULL);
+ 	if (!upstream
+ 	    || !upstream->merge
+ 	    || !upstream->merge[0]->dst)
+ 		return error("No upstream branch found for '%s'", cp);
+ 	free(cp);
+ 	cp = shorten_unambiguous_ref(upstream->merge[0]->dst, 0);
+ 	strbuf_reset(buf);
+ 	strbuf_addstr(buf, cp);
+ 	free(cp);
+ 	return len;
+ }
+ 
  /*
   * This is like "get_sha1_basic()", except it allows "sha1 expressions",
   * notably "xyz^" for "parent of xyz"