func assertNImages(graph *docker.Graph, t *testing.T, n int) {
if images, err := graph.Map(); err != nil {
t.Fatal(err)
} else if actualN := len(images); actualN != n {
t.Fatalf("Expected %d images, found %d", n, actualN)
}
}
func createTestImage(graph *docker.Graph, t *testing.T) *docker.Image {
archive, err := fakeTar()
if err != nil {
t.Fatal(err)
}
img, err := graph.Create(archive, nil, "Test image", "", nil)
if err != nil {
t.Fatal(err)
}
return img
}
func nukeGraph(graph *docker.Graph) {
graph.Driver().Cleanup()
os.RemoveAll(graph.Root)
}