new file mode 100644

@@ -0,0 +1,55 @@

+package client

+

+import (

+	"bytes"

+	"encoding/json"

+	"fmt"

+	"io/ioutil"

+	"net/http"

+	"strings"

+	"testing"

+

+	"github.com/docker/docker/api/types"

+	"golang.org/x/net/context"

+)

+

+func TestDiskUsageError(t *testing.T) {

+	client := &Client{

+		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),

+	}

+	_, err := client.DiskUsage(context.Background())

+	if err == nil || err.Error() != "Error response from daemon: Server error" {

+		t.Fatalf("expected a Server Error, got %v", err)

+	}

+}

+

+func TestDiskUsage(t *testing.T) {

+	expectedURL := "/system/df"

+	client := &Client{

+		client: newMockClient(func(req *http.Request) (*http.Response, error) {

+			if !strings.HasPrefix(req.URL.Path, expectedURL) {

+				return nil, fmt.Errorf("Expected URL '%s', got '%s'", expectedURL, req.URL)

+			}

+

+			du := types.DiskUsage{

+				LayersSize: int64(100),

+				Images:     nil,

+				Containers: nil,

+				Volumes:    nil,

+			}

+

+			b, err := json.Marshal(du)

+			if err != nil {

+				return nil, err

+			}

+

+			return &http.Response{

+				StatusCode: http.StatusOK,

+				Body:       ioutil.NopCloser(bytes.NewReader(b)),

+			}, nil

+		}),

+	}

+	if _, err := client.DiskUsage(context.Background()); err != nil {

+		t.Fatal(err)

+	}

+}