[PATCH 16/19] transport-helper: change import semantics

[Sverre Rabbelier <srabbelier@gmail.com>]

Currently the helper must somehow guess how many import statements to
read before it starts outputting its fast-export stream. This is
because the remote helper infrastructure runs fast-import only once,
so the helper is forced to output one stream for all import commands
it will receive. The only reason this worked in the past was because
only one ref was imported at a time.

Change the semantics of the import statement such that it matches
that of the list statement. That is, 'import\n' is followed by a list
of refs that should be exported, followed by '\n'.

Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
---

  Unchanged from my original series. Replaces Peff's workaround from
  his series.

 git-remote-testgit.py     |   14 +++++++++++---
 t/t5800-remote-helpers.sh |    2 +-
 transport-helper.c        |    7 ++++++-
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/git-remote-testgit.py b/git-remote-testgit.py
index 47a30da..88bcb20 100644
--- a/git-remote-testgit.py
+++ b/git-remote-testgit.py
@@ -115,14 +115,22 @@ def do_import(repo, args):
     """Exports a fast-import stream from testgit for git to import.
     """
 
-    if len(args) != 1:
-        die("Import needs exactly one ref")
+    if args:
+        die("Import expects its ref seperately")
 
     if not repo.gitdir:
         die("Need gitdir to import")
 
+    refs = []
+
+    while True:
+        line = sys.stdin.readline()
+        if line == '\n':
+            break
+        refs.append(line.strip())
+
     repo = update_local_repo(repo)
-    repo.exporter.export_repo(repo.gitdir, args)
+    repo.exporter.export_repo(repo.gitdir, refs)
 
     print "done"
 
diff --git a/t/t5800-remote-helpers.sh b/t/t5800-remote-helpers.sh
index a4afe38..682f813 100755
--- a/t/t5800-remote-helpers.sh
+++ b/t/t5800-remote-helpers.sh
@@ -94,7 +94,7 @@ test_expect_success PYTHON_24 'fetch new branch' '
 	compare_refs public HEAD localclone FETCH_HEAD
 '
 
-test_expect_failure PYTHON_24 'fetch multiple branches' '
+test_expect_success PYTHON_24 'fetch multiple branches' '
 	(cd localclone &&
 	 git fetch
 	) &&
diff --git a/transport-helper.c b/transport-helper.c
index bb1b97f..c089928 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -404,15 +404,20 @@ static int fetch_with_import(struct transport *transport,
 	if (get_importer(transport, &fastimport))
 		die("Couldn't run fast-import");
 
+	write_constant(data->helper->in, "import\n");
+
 	for (i = 0; i < nr_heads; i++) {
 		posn = to_fetch[i];
 		if (posn->status & REF_STATUS_UPTODATE)
 			continue;
 
-		strbuf_addf(&buf, "import %s\n", posn->name);
+		strbuf_addf(&buf, "%s\n", posn->name);
 		sendline(data, &buf);
 		strbuf_reset(&buf);
 	}
+
+	write_constant(data->helper->in, "\n");
+
 	if (finish_command(&fastimport))
 		die("Error while running fast-import");
 	free(fastimport.argv);
-- 
1.7.5.1.292.g728120