[PATCH 0/9] transport-helper: updates

@@ -814,6 +814,9 @@ static int push_refs_with_export(struct transport *transport,
 			die("helper %s does not support dry-run", data->name);
 	}
 
+	if (flags & TRANSPORT_PUSH_FORCE)
+		set_helper_option(transport, "force", "true");
+
 	helper = get_helper(transport);
 
 	write_constant(helper->in, "export\n");

@@ -630,7 +630,7 @@ static int push_update_ref_status(struct strbuf *buf,
 				   struct ref *remote_refs)
 {
 	char *refname, *msg;
-	int status;
+	int status, forced = 0;
 
 	if (!prefixcmp(buf->buf, "ok ")) {
 		status = REF_STATUS_OK;

@@ -683,6 +683,11 @@ static int push_update_ref_status(struct strbuf *buf,
 			free(msg);
 			msg = NULL;
 		}
+		else if (!strcmp(msg, "forced update")) {
+			forced = 1;
+			free(msg);
+			msg = NULL;
+		}
 	}
 
 	if (*ref)

@@ -704,6 +709,7 @@ static int push_update_ref_status(struct strbuf *buf,
 	}
 
 	(*ref)->status = status;
+	(*ref)->forced_update = forced;
 	(*ref)->remote_status = msg;
 	return !(status == REF_STATUS_OK);
 }

@@ -694,8 +694,9 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	revs.topo_order = 1;
 	revs.show_source = 1;
 	revs.rewrite_parents = 1;
+	argc = parse_options(argc, argv, prefix, options, fast_export_usage,
+			PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN);
 	argc = setup_revisions(argc, argv, &revs, NULL);
-	argc = parse_options(argc, argv, prefix, options, fast_export_usage, 0);
 	if (argc > 1)
 		usage_with_options (fast_export_usage, options);
 

@@ -105,6 +105,10 @@ marks the same across runs.
 	in the commit (as opposed to just listing the files which are
 	different from the commit's first parent).
 
+--refspec::
+	Apply the specified refspec to each ref exported. Multiple of them can
+	be specified.
+
 [<git-rev-list-args>...]::
 	A list of arguments, acceptable to 'git rev-parse' and
 	'git rev-list', that specifies the specific objects and references

@@ -17,6 +17,7 @@
 #include "utf8.h"
 #include "parse-options.h"
 #include "quote.h"
+#include "remote.h"
 
 static const char *fast_export_usage[] = {
 	N_("git fast-export [rev-list-opts]"),

@@ -30,6 +31,8 @@ static int fake_missing_tagger;
 static int use_done_feature;
 static int no_data;
 static int full_tree;
+static struct refspec *refspecs;
+static int refspecs_nr;
 
 static int parse_opt_signed_tag_mode(const struct option *opt,
 				     const char *arg, int unset)

@@ -502,6 +505,15 @@ static void get_tags_and_duplicates(struct rev_cmdline_info *info,
 		if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
 			continue;
 
+		if (refspecs) {
+			char *private;
+			private = apply_refspecs(refspecs, refspecs_nr, full_name);
+			if (private) {
+				free(full_name);
+				full_name = private;
+			}
+		}
+
 		switch (e->item->type) {
 		case OBJ_COMMIT:
 			commit = (struct commit *)e->item;

@@ -661,6 +673,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	struct commit *commit;
 	char *export_filename = NULL, *import_filename = NULL;
 	uint32_t lastimportid;
+	struct string_list refspecs_list;
 	struct option options[] = {
 		OPT_INTEGER(0, "progress", &progress,
 			    N_("show progress after <n> objects")),

@@ -681,6 +694,8 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 		OPT_BOOLEAN(0, "use-done-feature", &use_done_feature,
 			     N_("Use the done feature to terminate the stream")),
 		OPT_BOOL(0, "no-data", &no_data, N_("Skip output of blob data")),
+		OPT_STRING_LIST(0, "refspec", &refspecs_list, N_("refspec"),
+			     N_("Apply refspec to exported refs")),
 		OPT_END()
 	};
 

@@ -700,6 +715,19 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	if (argc > 1)
 		usage_with_options (fast_export_usage, options);
 
+	if (refspecs_list.nr) {
+		const char *refspecs_str[refspecs_list.nr];
+		int i;
+
+		for (i = 0; i < refspecs_list.nr; i++)
+			refspecs_str[i] = refspecs_list.items[i].string;
+
+		refspecs_nr = refspecs_list.nr;
+		refspecs = parse_fetch_refspec(refspecs_nr, refspecs_str);
+
+		string_list_clear(&refspecs_list, 1);
+	}
+
 	if (use_done_feature)
 		printf("feature done\n");
 

@@ -734,5 +762,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	if (use_done_feature)
 		printf("done\n");
 
+	free_refspec(refspecs_nr, refspecs);
+
 	return 0;
 }

@@ -504,4 +504,11 @@ test_expect_success 'refs are updated even if no commits need to be exported' '
 	test_cmp expected actual
 '
 
+test_expect_success 'use refspec' '
+	git fast-export --refspec refs/heads/master:refs/heads/foobar master | \
+		grep "^commit " | sort | uniq > actual &&
+	echo "commit refs/heads/foobar" > expected &&
+	test_cmp expected actual
+'
+
 test_done

@@ -87,7 +87,7 @@ test_expect_success 'push new branch by name' '
 	compare_refs local HEAD server refs/heads/new-name
 '
 
-test_expect_failure 'push new branch with old:new refspec' '
+test_expect_success 'push new branch with old:new refspec' '
 	(cd local &&
 	 git push origin new-name:new-refspec
 	) &&

@@ -809,7 +809,7 @@ static int push_refs_with_export(struct transport *transport,
 	struct ref *ref;
 	struct child_process *helper, exporter;
 	struct helper_data *data = transport->data;
-	struct string_list revlist_args = STRING_LIST_INIT_NODUP;
+	struct string_list revlist_args = STRING_LIST_INIT_DUP;
 	struct strbuf buf = STRBUF_INIT;
 
 	if (!data->refspecs)

@@ -848,8 +848,13 @@ static int push_refs_with_export(struct transport *transport,
 			die("remote-helpers do not support ref deletion");
 
 		if (ref->peer_ref) {
-			if (strcmp(ref->peer_ref->name, ref->name))
-				die("remote-helpers do not support old:new syntax");
+			if (strcmp(ref->name, ref->peer_ref->name)) {
+				struct strbuf buf = STRBUF_INIT;
+				strbuf_addf(&buf, "%s:%s", ref->peer_ref->name, ref->name);
+				string_list_append(&revlist_args, "--refspec");
+				string_list_append(&revlist_args, buf.buf);
+				strbuf_release(&buf);
+			}
 			string_list_append(&revlist_args, ref->peer_ref->name);
 		}
 	}

@@ -857,6 +862,8 @@ static int push_refs_with_export(struct transport *transport,
 	if (get_exporter(transport, &exporter, &revlist_args))
 		die("Couldn't run fast-export");
 
+	string_list_clear(&revlist_args, 1);
+
 	if (finish_command(&exporter))
 		die("Error while running fast-export");
 	push_update_refs_status(data, remote_refs);

@@ -483,6 +483,9 @@ Marks must be declared (via `mark`) before they can be used.
 * Any valid Git SHA-1 expression that resolves to a commit.  See
   ``SPECIFYING REVISIONS'' in linkgit:gitrevisions[7] for details.
 
+* The special null SHA-1 (40 zeros) specifices that the branch is to be
+  removed.
+
 The special case of restarting an incremental import from the
 current branch value should be written as:
 ----

@@ -248,6 +248,7 @@ struct branch {
 	uintmax_t last_commit;
 	uintmax_t num_notes;
 	unsigned active : 1;
+	unsigned delete : 1;
 	unsigned pack_id : PACK_ID_BITS;
 	unsigned char sha1[20];
 };

@@ -1674,10 +1675,13 @@ static int update_branch(struct branch *b)
 	struct ref_lock *lock;
 	unsigned char old_sha1[20];
 
-	if (is_null_sha1(b->sha1))
-		return 0;
 	if (read_ref(b->name, old_sha1))
 		hashclr(old_sha1);
+	if (is_null_sha1(b->sha1)) {
+		if (b->delete)
+			delete_ref(b->name, old_sha1, 0);
+		return 0;
+	}
 	lock = lock_any_ref_for_update(b->name, old_sha1, 0);
 	if (!lock)
 		return error("Unable to lock %s", b->name);

@@ -2604,8 +2608,11 @@ static int parse_from(struct branch *b)
 			free(buf);
 		} else
 			parse_from_existing(b);
-	} else if (!get_sha1(from, b->sha1))
+	} else if (!get_sha1(from, b->sha1)) {
 		parse_from_existing(b);
+		if (is_null_sha1(b->sha1))
+			b->delete = 1;
+	}
 	else
 		die("Invalid ref name or SHA1 expression: %s", from);
 

@@ -2934,4 +2934,22 @@ test_expect_success 'S: ls with garbage after sha1 must fail' '
 	test_i18ngrep "space after tree-ish" err
 '
 
+test_expect_success 'T: delete branch' '
+	git branch to-delete &&
+	git fast-import <<-EOF &&
+	reset refs/heads/to-delete
+	from 0000000000000000000000000000000000000000
+	EOF
+	test_must_fail git rev-parse --verify refs/heads/to-delete
+'
+
+test_expect_success 'T: empty reset doesnt delete branch' '
+	git branch not-to-delete &&
+	git fast-import <<-EOF &&
+	reset refs/heads/not-to-delete
+	EOF
+	git show-ref &&
+	git rev-parse --verify refs/heads/not-to-delete
+'
+
 test_done

@@ -665,6 +665,19 @@ static void import_marks(char *input_file)
 	fclose(f);
 }
 
+static void handle_deletes(void)
+{
+	int i;
+	for (i = 0; i < refspecs_nr; i++) {
+		struct refspec *refspec = &refspecs[i];
+		if (*refspec->src)
+			continue;
+
+		printf("reset %s\nfrom %s\n\n",
+			refspec->dst, sha1_to_hex(null_sha1));
+	}
+}
+
 int cmd_fast_export(int argc, const char **argv, const char *prefix)
 {
 	struct rev_info revs;

@@ -755,6 +768,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	}
 
 	handle_tags_and_duplicates(&extra_refs);
+	handle_deletes();
 
 	if (export_filename && lastimportid != last_idnum)
 		export_marks(export_filename);

@@ -511,4 +511,15 @@ test_expect_success 'use refspec' '
 	test_cmp expected actual
 '
 
+test_expect_success 'delete refspec' '
+	git branch to-delete &&
+	git fast-export --refspec :refs/heads/to-delete to-delete ^to-delete > actual &&
+	cat > expected <<-EOF &&
+	reset refs/heads/to-delete
+	from 0000000000000000000000000000000000000000
+
+	EOF
+	test_cmp expected actual
+'
+
 test_done

@@ -94,6 +94,14 @@ test_expect_success 'push new branch with old:new refspec' '
 	compare_refs local HEAD server refs/heads/new-refspec
 '
 
+test_expect_success 'push delete branch' '
+	(cd local &&
+	 git push origin :new-name
+	) &&
+	test_must_fail git --git-dir="server/.git" \
+	 rev-parse --verify refs/heads/new-name
+'
+
 test_expect_success 'cloning without refspec' '
 	GIT_REMOTE_TESTGIT_REFSPEC="" \
 	git clone "testgit::${PWD}/server" local2 2>error &&

@@ -844,18 +844,19 @@ static int push_refs_with_export(struct transport *transport,
 		}
 		free(private);
 
-		if (ref->deletion)
-			die("remote-helpers do not support ref deletion");
-
 		if (ref->peer_ref) {
 			if (strcmp(ref->name, ref->peer_ref->name)) {
 				struct strbuf buf = STRBUF_INIT;
-				strbuf_addf(&buf, "%s:%s", ref->peer_ref->name, ref->name);
+				if (!ref->deletion)
+					strbuf_addf(&buf, "%s:%s", ref->peer_ref->name, ref->name);
+				else
+					strbuf_addf(&buf, ":%s", ref->name);
 				string_list_append(&revlist_args, "--refspec");
 				string_list_append(&revlist_args, buf.buf);
 				strbuf_release(&buf);
 			}
-			string_list_append(&revlist_args, ref->peer_ref->name);
+			if (!ref->deletion)
+				string_list_append(&revlist_args, ref->peer_ref->name);
 		}
 	}
 

@@ -715,7 +715,8 @@ static int push_update_ref_status(struct strbuf *buf,
 }
 
 static void push_update_refs_status(struct helper_data *data,
-				    struct ref *remote_refs)
+				    struct ref *remote_refs,
+				    int flags)
 {
 	struct strbuf buf = STRBUF_INIT;
 	struct ref *ref = remote_refs;

@@ -729,7 +730,7 @@ static void push_update_refs_status(struct helper_data *data,
 		if (push_update_ref_status(&buf, &ref, remote_refs))
 			continue;
 
-		if (!data->refspecs)
+		if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs)
 			continue;
 
 		/* propagate back the update to the remote namespace */

@@ -799,7 +800,7 @@ static int push_refs_with_push(struct transport *transport,
 	sendline(data, &buf);
 	strbuf_release(&buf);
 
-	push_update_refs_status(data, remote_refs);
+	push_update_refs_status(data, remote_refs, flags);
 	return 0;
 }
 

@@ -867,7 +868,7 @@ static int push_refs_with_export(struct transport *transport,
 
 	if (finish_command(&exporter))
 		die("Error while running fast-export");
-	push_update_refs_status(data, remote_refs);
+	push_update_refs_status(data, remote_refs, flags);
 	return 0;
 }
 

@@ -874,9 +874,6 @@ static int push_refs_with_export(struct transport *transport,
 		char *private;
 		unsigned char sha1[20];

-		if (ref->deletion)
-			die("remote-helpers do not support ref deletion");
-
 		private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
 		if (private && !get_sha1(private, sha1)) {
 			strbuf_addf(&buf, "^%s", private);