Prefix / to the container name is ignored when container is renamed

Closes #10996

Signed-off-by: Srini Brahmaroutu <srbrahma@us.ibm.com>

Dockerfile

@@ -119,7 +119,7 @@ RUN set -x \
 		go build -o /go/bin/registry-v2 github.com/docker/distribution/cmd/registry
 
 # Get the "docker-py" source so we can run their integration tests
-ENV DOCKER_PY_COMMIT d39da1167975aaeb6c423b99621ecda1223477b8
+ENV DOCKER_PY_COMMIT 91985b239764fe54714fa0a93d52aa362357d251
 RUN git clone https://github.com/docker/docker-py.git /docker-py \
 	&& cd /docker-py \
 	&& git checkout -q $DOCKER_PY_COMMIT

daemon/rename.go

@@ -20,7 +20,7 @@ func (daemon *Daemon) ContainerRename(job *engine.Job) engine.Status {
 
 	container.Lock()
 	defer container.Unlock()
-	if _, err := daemon.reserveName(container.ID, newName); err != nil {
+	if newName, err = daemon.reserveName(container.ID, newName); err != nil {
 		return job.Errorf("Error when allocating new name: %s", err)
 	}
 

integration-cli/docker_cli_rename_test.go

@@ -35,7 +35,7 @@ func TestRenameStoppedContainer(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if name != "new_name" {
+	if name != "/new_name" {
 		t.Fatal("Failed to rename container ", name)
 	}
 
@@ -62,7 +62,7 @@ func TestRenameRunningContainer(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if name != "new_name" {
+	if name != "/new_name" {
 		t.Fatal("Failed to rename container ")
 	}
 
@@ -88,7 +88,7 @@ func TestRenameCheckNames(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if name != "new_name" {
+	if name != "/new_name" {
 		t.Fatal("Failed to rename container ")
 	}