Merge branch 'jk/at-push-sha1'

Introduce <branch>@{push} short-hand to denote the remote-tracking
branch that tracks the branch at the remote the <branch> would be
pushed to.

* jk/at-push-sha1:
  for-each-ref: accept "%(push)" format
  for-each-ref: use skip_prefix instead of starts_with
  sha1_name: implement @{push} shorthand
  sha1_name: refactor interpret_upstream_mark
  sha1_name: refactor upstream_mark
  remote.c: add branch_get_push
  remote.c: return upstream name from stat_tracking_info
  remote.c: untangle error logic in branch_get_upstream
  remote.c: report specific errors from branch_get_upstream
  remote.c: introduce branch_get_upstream helper
  remote.c: hoist read_config into remote_get_1
  remote.c: provide per-branch pushremote name
  remote.c: hoist branch.*.remote lookup out of remote_get_1
  remote.c: drop "remote" pointer from "struct branch"
  remote.c: refactor setup of branch->merge list
  remote.c: drop default_remote_name variable

Documentation/git-for-each-ref.txt

@@ -97,6 +97,12 @@ upstream::
 	or "=" (in sync).  Has no effect if the ref does not have
 	tracking information associated with it.
 
+push::
+	The name of a local ref which represents the `@{push}` location
+	for the displayed ref. Respects `:short`, `:track`, and
+	`:trackshort` options as `upstream` does. Produces an empty
+	string if no `@{push}` ref is configured.
+
 HEAD::
 	'*' if HEAD matches current ref (the checked out branch), ' '
 	otherwise.

Documentation/revisions.txt

@@ -98,6 +98,31 @@ some output processing may assume ref names in UTF-8.
   `branch.<name>.merge`).  A missing branchname defaults to the
   current one.
 
+'<branchname>@\{push\}', e.g. 'master@\{push\}', '@\{push\}'::
+  The suffix '@\{push}' reports the branch "where we would push to" if
+  `git push` were run while `branchname` was checked out (or the current
+  'HEAD' if no branchname is specified). Since our push destination is
+  in a remote repository, of course, we report the local tracking branch
+  that corresponds to that branch (i.e., something in 'refs/remotes/').
++
+Here's an example to make it more clear:
++
+------------------------------
+$ git config push.default current
+$ git config remote.pushdefault myfork
+$ git checkout -b mybranch origin/master
+
+$ git rev-parse --symbolic-full-name @{upstream}
+refs/remotes/origin/master
+
+$ git rev-parse --symbolic-full-name @{push}
+refs/remotes/myfork/mybranch
+------------------------------
++
+Note in the example that we set up a triangular workflow, where we pull
+from one location and push to another. In a non-triangular workflow,
+'@\{push}' is the same as '@\{upstream}', and there is no need for it.
+
 '<rev>{caret}', e.g. 'HEAD{caret}, v1.5.1{caret}0'::
   A suffix '{caret}' to a revision parameter means the first parent of
   that commit object.  '{caret}<n>' means the <n>th parent (i.e.

Documentation/technical/api-remote.txt

@@ -97,10 +97,6 @@ It contains:
 
 	The name of the remote listed in the configuration.
 
-`remote`::
-
-	The struct remote for that remote.
-
 `merge_name`::
 
 	An array of the "merge" lines in the configuration.

builtin/branch.c

@@ -123,14 +123,12 @@ static int branch_merged(int kind, const char *name,
 
 	if (kind == REF_LOCAL_BRANCH) {
 		struct branch *branch = branch_get(name);
+		const char *upstream = branch_get_upstream(branch, NULL);
 		unsigned char sha1[20];
 
-		if (branch &&
-		    branch->merge &&
-		    branch->merge[0] &&
-		    branch->merge[0]->dst &&
+		if (upstream &&
 		    (reference_name = reference_name_to_free =
-		     resolve_refdup(branch->merge[0]->dst, RESOLVE_REF_READING,
+		     resolve_refdup(upstream, RESOLVE_REF_READING,
 				    sha1, NULL)) != NULL)
 			reference_rev = lookup_commit_reference(sha1);
 	}
@@ -427,25 +425,19 @@ static void fill_tracking_info(struct strbuf *stat, const char *branch_name,
 	int ours, theirs;
 	char *ref = NULL;
 	struct branch *branch = branch_get(branch_name);
+	const char *upstream;
 	struct strbuf fancy = STRBUF_INIT;
 	int upstream_is_gone = 0;
 	int added_decoration = 1;
 
-	switch (stat_tracking_info(branch, &ours, &theirs)) {
-	case 0:
-		/* no base */
-		return;
-	case -1:
-		/* with "gone" base */
+	if (stat_tracking_info(branch, &ours, &theirs, &upstream) < 0) {
+		if (!upstream)
+			return;
 		upstream_is_gone = 1;
-		break;
-	default:
-		/* with base */
-		break;
 	}
 
 	if (show_upstream_ref) {
-		ref = shorten_unambiguous_ref(branch->merge[0]->dst, 0);
+		ref = shorten_unambiguous_ref(upstream, 0);
 		if (want_color(branch_use_color))
 			strbuf_addf(&fancy, "%s%s%s",
 					branch_get_color(BRANCH_COLOR_UPSTREAM),

builtin/for-each-ref.c

@@ -74,6 +74,7 @@ static struct {
 	{ "contents:body" },
 	{ "contents:signature" },
 	{ "upstream" },
+	{ "push" },
 	{ "symref" },
 	{ "flag" },
 	{ "HEAD" },
@@ -659,15 +660,26 @@ static void populate_value(struct refinfo *ref)
 		else if (starts_with(name, "symref"))
 			refname = ref->symref ? ref->symref : "";
 		else if (starts_with(name, "upstream")) {
+			const char *branch_name;
 			/* only local branches may have an upstream */
-			if (!starts_with(ref->refname, "refs/heads/"))
+			if (!skip_prefix(ref->refname, "refs/heads/",
+					 &branch_name))
 				continue;
-			branch = branch_get(ref->refname + 11);
+			branch = branch_get(branch_name);
 
-			if (!branch || !branch->merge || !branch->merge[0] ||
-			    !branch->merge[0]->dst)
+			refname = branch_get_upstream(branch, NULL);
+			if (!refname)
+				continue;
+		} else if (starts_with(name, "push")) {
+			const char *branch_name;
+			if (!skip_prefix(ref->refname, "refs/heads/",
+					 &branch_name))
+				continue;
+			branch = branch_get(branch_name);
+
+			refname = branch_get_push(branch, NULL);
+			if (!refname)
 				continue;
-			refname = branch->merge[0]->dst;
 		} else if (starts_with(name, "color:")) {
 			char color[COLOR_MAXLEN] = "";
 
@@ -713,11 +725,12 @@ static void populate_value(struct refinfo *ref)
 				refname = shorten_unambiguous_ref(refname,
 						      warn_ambiguous_refs);
 			else if (!strcmp(formatp, "track") &&
-				 starts_with(name, "upstream")) {
+				 (starts_with(name, "upstream") ||
+				  starts_with(name, "push"))) {
 				char buf[40];
 
 				if (stat_tracking_info(branch, &num_ours,
-						       &num_theirs) != 1)
+						       &num_theirs, NULL))
 					continue;
 
 				if (!num_ours && !num_theirs)
@@ -735,11 +748,12 @@ static void populate_value(struct refinfo *ref)
 				}
 				continue;
 			} else if (!strcmp(formatp, "trackshort") &&
-				   starts_with(name, "upstream")) {
+				   (starts_with(name, "upstream") ||
+				    starts_with(name, "push"))) {
 				assert(branch);
 
 				if (stat_tracking_info(branch, &num_ours,
-							&num_theirs) != 1)
+							&num_theirs, NULL))
 					continue;
 
 				if (!num_ours && !num_theirs)

builtin/log.c

@@ -1632,16 +1632,13 @@ int cmd_cherry(int argc, const char **argv, const char *prefix)
 		break;
 	default:
 		current_branch = branch_get(NULL);
-		if (!current_branch || !current_branch->merge
-					|| !current_branch->merge[0]
-					|| !current_branch->merge[0]->dst) {
+		upstream = branch_get_upstream(current_branch, NULL);
+		if (!upstream) {
 			fprintf(stderr, _("Could not find a tracked"
 					" remote branch, please"
 					" specify <upstream> manually.\n"));
 			usage_with_options(cherry_usage, options);
 		}
-
-		upstream = current_branch->merge[0]->dst;
 	}
 
 	init_revisions(&revs, prefix);

builtin/merge.c

@@ -933,7 +933,7 @@ static int setup_with_upstream(const char ***argv)
 
 	if (!branch)
 		die(_("No current branch."));
-	if (!branch->remote)
+	if (!branch->remote_name)
 		die(_("No remote for the current branch."));
 	if (!branch->merge_nr)
 		die(_("No default upstream defined for the current branch."));

remote.c

@@ -49,10 +49,7 @@ static int branches_alloc;
 static int branches_nr;
 
 static struct branch *current_branch;
-static const char *default_remote_name;
-static const char *branch_pushremote_name;
 static const char *pushremote_name;
-static int explicit_default_remote_name;
 
 static struct rewrites rewrites;
 static struct rewrites rewrites_push;
@@ -367,16 +364,9 @@ static int handle_config(const char *key, const char *value, void *cb)
 			return 0;
 		branch = make_branch(name, subkey - name);
 		if (!strcmp(subkey, ".remote")) {
-			if (git_config_string(&branch->remote_name, key, value))
-				return -1;
-			if (branch == current_branch) {
-				default_remote_name = branch->remote_name;
-				explicit_default_remote_name = 1;
-			}
+			return git_config_string(&branch->remote_name, key, value);
 		} else if (!strcmp(subkey, ".pushremote")) {
-			if (branch == current_branch)
-				if (git_config_string(&branch_pushremote_name, key, value))
-					return -1;
+			return git_config_string(&branch->pushremote_name, key, value);
 		} else if (!strcmp(subkey, ".merge")) {
 			if (!value)
 				return config_error_nonbool(key);
@@ -501,12 +491,15 @@ static void alias_all_urls(void)
 
 static void read_config(void)
 {
+	static int loaded;
 	unsigned char sha1[20];
 	const char *head_ref;
 	int flag;
-	if (default_remote_name) /* did this already */
+
+	if (loaded)
 		return;
-	default_remote_name = "origin";
+	loaded = 1;
+
 	current_branch = NULL;
 	head_ref = resolve_ref_unsafe("HEAD", 0, sha1, &flag);
 	if (head_ref && (flag & REF_ISSYMREF) &&
@@ -514,10 +507,6 @@ static void read_config(void)
 		current_branch = make_branch(head_ref, 0);
 	}
 	git_config(handle_config, NULL);
-	if (branch_pushremote_name) {
-		free((char *)pushremote_name);
-		pushremote_name = branch_pushremote_name;
-	}
 	alias_all_urls();
 }
 
@@ -696,22 +685,45 @@ static int valid_remote_nick(const char *name)
 	return !strchr(name, '/'); /* no slash */
 }
 
-static struct remote *remote_get_1(const char *name, const char *pushremote_name)
+const char *remote_for_branch(struct branch *branch, int *explicit)
+{
+	if (branch && branch->remote_name) {
+		if (explicit)
+			*explicit = 1;
+		return branch->remote_name;
+	}
+	if (explicit)
+		*explicit = 0;
+	return "origin";
+}
+
+const char *pushremote_for_branch(struct branch *branch, int *explicit)
+{
+	if (branch && branch->pushremote_name) {
+		if (explicit)
+			*explicit = 1;
+		return branch->pushremote_name;
+	}
+	if (pushremote_name) {
+		if (explicit)
+			*explicit = 1;
+		return pushremote_name;
+	}
+	return remote_for_branch(branch, explicit);
+}
+
+static struct remote *remote_get_1(const char *name,
+				   const char *(*get_default)(struct branch *, int *))
 {
 	struct remote *ret;
 	int name_given = 0;
 
+	read_config();
+
 	if (name)
 		name_given = 1;
-	else {
-		if (pushremote_name) {
-			name = pushremote_name;
-			name_given = 1;
-		} else {
-			name = default_remote_name;
-			name_given = explicit_default_remote_name;
-		}
-	}
+	else
+		name = get_default(current_branch, &name_given);
 
 	ret = make_remote(name, 0);
 	if (valid_remote_nick(name)) {
@@ -731,14 +743,12 @@ static struct remote *remote_get_1(const char *name, const char *pushremote_name
 
 struct remote *remote_get(const char *name)
 {
-	read_config();
-	return remote_get_1(name, NULL);
+	return remote_get_1(name, remote_for_branch);
 }
 
 struct remote *pushremote_get(const char *name)
 {
-	read_config();
-	return remote_get_1(name, pushremote_name);
+	return remote_get_1(name, pushremote_for_branch);
 }
 
 int remote_is_configured(const char *name)
@@ -1633,15 +1643,31 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
 
 static void set_merge(struct branch *ret)
 {
+	struct remote *remote;
 	char *ref;
 	unsigned char sha1[20];
 	int i;
 
+	if (!ret)
+		return; /* no branch */
+	if (ret->merge)
+		return; /* already run */
+	if (!ret->remote_name || !ret->merge_nr) {
+		/*
+		 * no merge config; let's make sure we don't confuse callers
+		 * with a non-zero merge_nr but a NULL merge
+		 */
+		ret->merge_nr = 0;
+		return;
+	}
+
+	remote = remote_get(ret->remote_name);
+
 	ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
 	for (i = 0; i < ret->merge_nr; i++) {
 		ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
 		ret->merge[i]->src = xstrdup(ret->merge_name[i]);
-		if (!remote_find_tracking(ret->remote, ret->merge[i]) ||
+		if (!remote_find_tracking(remote, ret->merge[i]) ||
 		    strcmp(ret->remote_name, "."))
 			continue;
 		if (dwim_ref(ret->merge_name[i], strlen(ret->merge_name[i]),
@@ -1661,11 +1687,7 @@ struct branch *branch_get(const char *name)
 		ret = current_branch;
 	else
 		ret = make_branch(name, 0);
-	if (ret && ret->remote_name) {
-		ret->remote = remote_get(ret->remote_name);
-		if (ret->merge_nr)
-			set_merge(ret);
-	}
+	set_merge(ret);
 	return ret;
 }
 
@@ -1683,6 +1705,130 @@ int branch_merge_matches(struct branch *branch,
 	return refname_match(branch->merge[i]->src, refname);
 }
 
+__attribute((format (printf,2,3)))
+static const char *error_buf(struct strbuf *err, const char *fmt, ...)
+{
+	if (err) {
+		va_list ap;
+		va_start(ap, fmt);
+		strbuf_vaddf(err, fmt, ap);
+		va_end(ap);
+	}
+	return NULL;
+}
+
+const char *branch_get_upstream(struct branch *branch, struct strbuf *err)
+{
+	if (!branch)
+		return error_buf(err, _("HEAD does not point to a branch"));
+
+	if (!branch->merge || !branch->merge[0]) {
+		/*
+		 * no merge config; is it because the user didn't define any,
+		 * or because it is not a real branch, and get_branch
+		 * auto-vivified it?
+		 */
+		if (!ref_exists(branch->refname))
+			return error_buf(err, _("no such branch: '%s'"),
+					 branch->name);
+		return error_buf(err,
+				 _("no upstream configured for branch '%s'"),
+				 branch->name);
+	}
+
+	if (!branch->merge[0]->dst)
+		return error_buf(err,
+				 _("upstream branch '%s' not stored as a remote-tracking branch"),
+				 branch->merge[0]->src);
+
+	return branch->merge[0]->dst;
+}
+
+static const char *tracking_for_push_dest(struct remote *remote,
+					  const char *refname,
+					  struct strbuf *err)
+{
+	char *ret;
+
+	ret = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
+	if (!ret)
+		return error_buf(err,
+				 _("push destination '%s' on remote '%s' has no local tracking branch"),
+				 refname, remote->name);
+	return ret;
+}
+
+static const char *branch_get_push_1(struct branch *branch, struct strbuf *err)
+{
+	struct remote *remote;
+
+	if (!branch)
+		return error_buf(err, _("HEAD does not point to a branch"));
+
+	remote = remote_get(pushremote_for_branch(branch, NULL));
+	if (!remote)
+		return error_buf(err,
+				 _("branch '%s' has no remote for pushing"),
+				 branch->name);
+
+	if (remote->push_refspec_nr) {
+		char *dst;
+		const char *ret;
+
+		dst = apply_refspecs(remote->push, remote->push_refspec_nr,
+				     branch->refname);
+		if (!dst)
+			return error_buf(err,
+					 _("push refspecs for '%s' do not include '%s'"),
+					 remote->name, branch->name);
+
+		ret = tracking_for_push_dest(remote, dst, err);
+		free(dst);
+		return ret;
+	}
+
+	if (remote->mirror)
+		return tracking_for_push_dest(remote, branch->refname, err);
+
+	switch (push_default) {
+	case PUSH_DEFAULT_NOTHING:
+		return error_buf(err, _("push has no destination (push.default is 'nothing')"));
+
+	case PUSH_DEFAULT_MATCHING:
+	case PUSH_DEFAULT_CURRENT:
+		return tracking_for_push_dest(remote, branch->refname, err);
+
+	case PUSH_DEFAULT_UPSTREAM:
+		return branch_get_upstream(branch, err);
+
+	case PUSH_DEFAULT_UNSPECIFIED:
+	case PUSH_DEFAULT_SIMPLE:
+		{
+			const char *up, *cur;
+
+			up = branch_get_upstream(branch, err);
+			if (!up)
+				return NULL;
+			cur = tracking_for_push_dest(remote, branch->refname, err);
+			if (!cur)
+				return NULL;
+			if (strcmp(cur, up))
+				return error_buf(err,
+						 _("cannot resolve 'simple' push to a single destination"));
+			return cur;
+		}
+	}
+
+	die("BUG: unhandled push situation");
+}
+
+const char *branch_get_push(struct branch *branch, struct strbuf *err)
+{
+	if (!branch->push_tracking_ref)
+		branch->push_tracking_ref = branch_get_push_1(branch, err);
+	return branch->push_tracking_ref;
+}
+
 static int ignore_symref_update(const char *refname)
 {
 	unsigned char sha1[20];
@@ -1877,12 +2023,15 @@ int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
 
 /*
  * Compare a branch with its upstream, and save their differences (number
- * of commits) in *num_ours and *num_theirs.
+ * of commits) in *num_ours and *num_theirs. The name of the upstream branch
+ * (or NULL if no upstream is defined) is returned via *upstream_name, if it
+ * is not itself NULL.
  *
- * Return 0 if branch has no upstream (no base), -1 if upstream is missing
- * (with "gone" base), otherwise 1 (with base).
+ * Returns -1 if num_ours and num_theirs could not be filled in (e.g., no
+ * upstream defined, or ref does not exist), 0 otherwise.
  */
-int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
+int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
+		       const char **upstream_name)
 {
 	unsigned char sha1[20];
 	struct commit *ours, *theirs;
@@ -1892,12 +2041,13 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
 	int rev_argc;
 
 	/* Cannot stat unless we are marked to build on top of somebody else. */
-	if (!branch ||
-	    !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
-		return 0;
+	base = branch_get_upstream(branch, NULL);
+	if (upstream_name)
+		*upstream_name = base;
+	if (!base)
+		return -1;
 
 	/* Cannot stat if what we used to build on no longer exists */
-	base = branch->merge[0]->dst;
 	if (read_ref(base, sha1))
 		return -1;
 	theirs = lookup_commit_reference(sha1);
@@ -1913,7 +2063,7 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
 	/* are we the same? */
 	if (theirs == ours) {
 		*num_theirs = *num_ours = 0;
-		return 1;
+		return 0;
 	}
 
 	/* Run "rev-list --left-right ours...theirs" internally... */
@@ -1949,7 +2099,7 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
 	/* clear object flags smudged by the above traversal */
 	clear_commit_marks(ours, ALL_REV_FLAGS);
 	clear_commit_marks(theirs, ALL_REV_FLAGS);
-	return 1;
+	return 0;
 }
 
 /*
@@ -1958,23 +2108,17 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
 int format_tracking_info(struct branch *branch, struct strbuf *sb)
 {
 	int ours, theirs;
+	const char *full_base;
 	char *base;
 	int upstream_is_gone = 0;
 
-	switch (stat_tracking_info(branch, &ours, &theirs)) {
-	case 0:
-		/* no base */
-		return 0;
-	case -1:
-		/* with "gone" base */
+	if (stat_tracking_info(branch, &ours, &theirs, &full_base) < 0) {
+		if (!full_base)
+			return 0;
 		upstream_is_gone = 1;
-		break;
-	default:
-		/* with base */
-		break;
 	}
 
-	base = shorten_unambiguous_ref(branch->merge[0]->dst, 0);
+	base = shorten_unambiguous_ref(full_base, 0);
 	if (upstream_is_gone) {
 		strbuf_addf(sb,
 			_("Your branch is based on '%s', but the upstream is gone.\n"),

remote.h

@@ -203,19 +203,42 @@ struct branch {
 	const char *refname;
 
 	const char *remote_name;
-	struct remote *remote;
+	const char *pushremote_name;
 
 	const char **merge_name;
 	struct refspec **merge;
 	int merge_nr;
 	int merge_alloc;
+
+	const char *push_tracking_ref;
 };
 
 struct branch *branch_get(const char *name);
+const char *remote_for_branch(struct branch *branch, int *explicit);
+const char *pushremote_for_branch(struct branch *branch, int *explicit);
 
 int branch_has_merge_config(struct branch *branch);
 int branch_merge_matches(struct branch *, int n, const char *);
 
+/**
+ * Return the fully-qualified refname of the tracking branch for `branch`.
+ * I.e., what "branch@{upstream}" would give you. Returns NULL if no
+ * upstream is defined.
+ *
+ * If `err` is not NULL and no upstream is defined, a more specific error
+ * message is recorded there (if the function does not return NULL, then
+ * `err` is not touched).
+ */
+const char *branch_get_upstream(struct branch *branch, struct strbuf *err);
+
+/**
+ * Return the tracking branch that corresponds to the ref we would push to
+ * given a bare `git push` while `branch` is checked out.
+ *
+ * The return value and `err` conventions match those of `branch_get_upstream`.
+ */
+const char *branch_get_push(struct branch *branch, struct strbuf *err);
+
 /* Flags to match_refs. */
 enum match_refs_flags {
 	MATCH_REFS_NONE		= 0,
@@ -226,7 +249,8 @@ enum match_refs_flags {
 };
 
 /* Reporting of tracking info */
-int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs);
+int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
+		       const char **upstream_name);
 int format_tracking_info(struct branch *branch, struct strbuf *sb);
 
 struct ref *get_local_heads(void);

sha1_name.c

@@ -416,12 +416,12 @@ static int ambiguous_path(const char *path, int len)
 	return slash;
 }
 
-static inline int upstream_mark(const char *string, int len)
+static inline int at_mark(const char *string, int len,
+			  const char **suffix, int nr)
 {
-	const char *suffix[] = { "@{upstream}", "@{u}" };
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(suffix); i++) {
+	for (i = 0; i < nr; i++) {
 		int suffix_len = strlen(suffix[i]);
 		if (suffix_len <= len
 		    && !memcmp(string, suffix[i], suffix_len))
@@ -430,6 +430,18 @@ static inline int upstream_mark(const char *string, int len)
 	return 0;
 }
 
+static inline int upstream_mark(const char *string, int len)
+{
+	const char *suffix[] = { "@{upstream}", "@{u}" };
+	return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
+}
+
+static inline int push_mark(const char *string, int len)
+{
+	const char *suffix[] = { "@{push}" };
+	return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
+}
+
 static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags);
 static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
 
@@ -477,7 +489,8 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1,
 					nth_prior = 1;
 					continue;
 				}
-				if (!upstream_mark(str + at, len - at)) {
+				if (!upstream_mark(str + at, len - at) &&
+				    !push_mark(str + at, len - at)) {
 					reflog_len = (len-1) - (at+2);
 					len = at;
 				}
@@ -1056,46 +1069,36 @@ static void set_shortened_ref(struct strbuf *buf, const char *ref)
 	free(s);
 }
 
-static const char *get_upstream_branch(const char *branch_buf, int len)
-{
-	char *branch = xstrndup(branch_buf, len);
-	struct branch *upstream = branch_get(*branch ? branch : NULL);
-
-	/*
-	 * Upstream can be NULL only if branch refers to HEAD and HEAD
-	 * points to something different than a branch.
-	 */
-	if (!upstream)
-		die(_("HEAD does not point to a branch"));
-	if (!upstream->merge || !upstream->merge[0]->dst) {
-		if (!ref_exists(upstream->refname))
-			die(_("No such branch: '%s'"), branch);
-		if (!upstream->merge) {
-			die(_("No upstream configured for branch '%s'"),
-				upstream->name);
-		}
-		die(
-			_("Upstream branch '%s' not stored as a remote-tracking branch"),
-			upstream->merge[0]->src);
-	}
-	free(branch);
-
-	return upstream->merge[0]->dst;
-}
-
-static int interpret_upstream_mark(const char *name, int namelen,
-				   int at, struct strbuf *buf)
+static int interpret_branch_mark(const char *name, int namelen,
+				 int at, struct strbuf *buf,
+				 int (*get_mark)(const char *, int),
+				 const char *(*get_data)(struct branch *,
+							 struct strbuf *))
 {
 	int len;
+	struct branch *branch;
+	struct strbuf err = STRBUF_INIT;
+	const char *value;
 
-	len = upstream_mark(name + at, namelen - at);
+	len = get_mark(name + at, namelen - at);
 	if (!len)
 		return -1;
 
 	if (memchr(name, ':', at))
 		return -1;
 
-	set_shortened_ref(buf, get_upstream_branch(name, at));
+	if (at) {
+		char *name_str = xmemdupz(name, at);
+		branch = branch_get(name_str);
+		free(name_str);
+	} else
+		branch = branch_get(NULL);
+
+	value = get_data(branch, &err);
+	if (!value)
+		die("%s", err.buf);
+
+	set_shortened_ref(buf, value);
 	return len + at;
 }
 
@@ -1146,7 +1149,13 @@ int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
 		if (len > 0)
 			return reinterpret(name, namelen, len, buf);
 
-		len = interpret_upstream_mark(name, namelen, at - name, buf);
+		len = interpret_branch_mark(name, namelen, at - name, buf,
+					    upstream_mark, branch_get_upstream);
+		if (len > 0)
+			return len;
+
+		len = interpret_branch_mark(name, namelen, at - name, buf,
+					    push_mark, branch_get_push);
 		if (len > 0)
 			return len;
 	}

t/t1507-rev-parse-upstream.sh

@@ -150,7 +150,7 @@ test_expect_success 'branch@{u} works when tracking a local branch' '
 
 test_expect_success 'branch@{u} error message when no upstream' '
 	cat >expect <<-EOF &&
-	fatal: No upstream configured for branch ${sq}non-tracking${sq}
+	fatal: no upstream configured for branch ${sq}non-tracking${sq}
 	EOF
 	error_message non-tracking@{u} 2>actual &&
 	test_i18ncmp expect actual
@@ -158,7 +158,7 @@ test_expect_success 'branch@{u} error message when no upstream' '
 
 test_expect_success '@{u} error message when no upstream' '
 	cat >expect <<-EOF &&
-	fatal: No upstream configured for branch ${sq}master${sq}
+	fatal: no upstream configured for branch ${sq}master${sq}
 	EOF
 	test_must_fail git rev-parse --verify @{u} 2>actual &&
 	test_i18ncmp expect actual
@@ -166,7 +166,7 @@ test_expect_success '@{u} error message when no upstream' '
 
 test_expect_success 'branch@{u} error message with misspelt branch' '
 	cat >expect <<-EOF &&
-	fatal: No such branch: ${sq}no-such-branch${sq}
+	fatal: no such branch: ${sq}no-such-branch${sq}
 	EOF
 	error_message no-such-branch@{u} 2>actual &&
 	test_i18ncmp expect actual
@@ -183,7 +183,7 @@ test_expect_success '@{u} error message when not on a branch' '
 
 test_expect_success 'branch@{u} error message if upstream branch not fetched' '
 	cat >expect <<-EOF &&
-	fatal: Upstream branch ${sq}refs/heads/side${sq} not stored as a remote-tracking branch
+	fatal: upstream branch ${sq}refs/heads/side${sq} not stored as a remote-tracking branch
 	EOF
 	error_message bad-upstream@{u} 2>actual &&
 	test_i18ncmp expect actual

t/t1514-rev-parse-push.sh

+#!/bin/sh
+
+test_description='test <branch>@{push} syntax'
+. ./test-lib.sh
+
+resolve () {
+	echo "$2" >expect &&
+	git rev-parse --symbolic-full-name "$1" >actual &&
+	test_cmp expect actual
+}
+
+test_expect_success 'setup' '
+	git init --bare parent.git &&
+	git init --bare other.git &&
+	git remote add origin parent.git &&
+	git remote add other other.git &&
+	test_commit base &&
+	git push origin HEAD &&
+	git branch --set-upstream-to=origin/master master &&
+	git branch --track topic origin/master &&
+	git push origin topic &&
+	git push other topic
+'
+
+test_expect_success '@{push} with default=nothing' '
+	test_config push.default nothing &&
+	test_must_fail git rev-parse master@{push}
+'
+
+test_expect_success '@{push} with default=simple' '
+	test_config push.default simple &&
+	resolve master@{push} refs/remotes/origin/master
+'
+
+test_expect_success 'triangular @{push} fails with default=simple' '
+	test_config push.default simple &&
+	test_must_fail git rev-parse topic@{push}
+'
+
+test_expect_success '@{push} with default=current' '
+	test_config push.default current &&
+	resolve topic@{push} refs/remotes/origin/topic
+'
+
+test_expect_success '@{push} with default=matching' '
+	test_config push.default matching &&
+	resolve topic@{push} refs/remotes/origin/topic
+'
+
+test_expect_success '@{push} with pushremote defined' '
+	test_config push.default current &&
+	test_config branch.topic.pushremote other &&
+	resolve topic@{push} refs/remotes/other/topic
+'
+
+test_expect_success '@{push} with push refspecs' '
+	test_config push.default nothing &&
+	test_config remote.origin.push refs/heads/*:refs/heads/magic/* &&
+	git push &&
+	resolve topic@{push} refs/remotes/origin/magic/topic
+'
+
+test_done

t/t6300-for-each-ref.sh

@@ -28,7 +28,10 @@ test_expect_success setup '
 	git update-ref refs/remotes/origin/master master &&
 	git remote add origin nowhere &&
 	git config branch.master.remote origin &&
-	git config branch.master.merge refs/heads/master
+	git config branch.master.merge refs/heads/master &&
+	git remote add myfork elsewhere &&
+	git config remote.pushdefault myfork &&
+	git config push.default current
 '
 
 test_atom() {
@@ -47,6 +50,7 @@ test_atom() {
 
 test_atom head refname refs/heads/master
 test_atom head upstream refs/remotes/origin/master
+test_atom head push refs/remotes/myfork/master
 test_atom head objecttype commit
 test_atom head objectsize 171
 test_atom head objectname $(git rev-parse refs/heads/master)
@@ -83,6 +87,7 @@ test_atom head HEAD '*'
 
 test_atom tag refname refs/tags/testtag
 test_atom tag upstream ''
+test_atom tag push ''
 test_atom tag objecttype tag
 test_atom tag objectsize 154
 test_atom tag objectname $(git rev-parse refs/tags/testtag)
@@ -347,6 +352,12 @@ test_expect_success 'Check that :track[short] works when upstream is invalid' '
 	test_cmp expected actual
 '
 
+test_expect_success '%(push) supports tracking specifiers, too' '
+	echo "[ahead 1]" >expected &&
+	git for-each-ref --format="%(push:track)" refs/heads >actual &&
+	test_cmp expected actual
+'
+
 cat >expected <<EOF
 $(git rev-parse --short HEAD)
 EOF

wt-status.c

@@ -1534,21 +1534,15 @@ static void wt_shortstatus_print_tracking(struct wt_status *s)
 
 	color_fprintf(s->fp, branch_color_local, "%s", branch_name);
 
-	switch (stat_tracking_info(branch, &num_ours, &num_theirs)) {
-	case 0:
-		/* no base */
-		fputc(s->null_termination ? '\0' : '\n', s->fp);
-		return;
-	case -1:
-		/* with "gone" base */
+	if (stat_tracking_info(branch, &num_ours, &num_theirs, &base) < 0) {
+		if (!base) {
+			fputc(s->null_termination ? '\0' : '\n', s->fp);
+			return;
+		}
+
 		upstream_is_gone = 1;
-		break;
-	default:
-		/* with base */
-		break;
 	}
 
-	base = branch->merge[0]->dst;
 	base = shorten_unambiguous_ref(base, 0);
 	color_fprintf(s->fp, header_color, "...");
 	color_fprintf(s->fp, branch_color_remote, "%s", base);