unit tests

Signed-off-by: Casey Lee <cplee@nektos.com>

pkg/container/docker_build.go

@@ -40,7 +40,8 @@ func NewDockerBuildExecutor(input NewDockerBuildExecutorInput) common.Executor {
 
 		tags := []string{input.ImageTag}
 		options := types.ImageBuildOptions{
-			Tags: tags,
+			Tags:   tags,
+			Remove: true,
 		}
 
 		buildContext, err := createBuildContext(input.ContextDir, "Dockerfile")

pkg/container/docker_images_test.go

@@ -19,27 +19,28 @@ func TestImageExistsLocally(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping integration test")
 	}
+	ctx := context.Background()
 	// to help make this test reliable and not flaky, we need to have
 	// an image that will exist, and onew that won't exist
 
-	exists, err := ImageExistsLocally(context.TODO(), "library/alpine:this-random-tag-will-never-exist")
+	exists, err := ImageExistsLocally(ctx, "library/alpine:this-random-tag-will-never-exist")
 	assert.Nil(t, err)
 	assert.Equal(t, false, exists)
 
 	// pull an image
 	cli, err := client.NewClientWithOpts(client.FromEnv)
 	assert.Nil(t, err)
-	cli.NegotiateAPIVersion(context.TODO())
+	cli.NegotiateAPIVersion(context.Background())
 
 	// Chose alpine latest because it's so small
 	// maybe we should build an image instead so that tests aren't reliable on dockerhub
-	reader, err := cli.ImagePull(context.TODO(), "alpine:latest", types.ImagePullOptions{})
+	reader, err := cli.ImagePull(ctx, "alpine:latest", types.ImagePullOptions{})
 	assert.Nil(t, err)
 	defer reader.Close()
 	_, err = ioutil.ReadAll(reader)
 	assert.Nil(t, err)
 
-	exists, err = ImageExistsLocally(context.TODO(), "alpine:latest")
+	exists, err = ImageExistsLocally(ctx, "alpine:latest")
 	assert.Nil(t, err)
 	assert.Equal(t, true, exists)
 }