@@ -3,15 +3,14 @@ package client // import "github.com/docker/docker/client"

 import (

 	"bytes"

 	"context"

-	"fmt"

 	"io"

 	"net/http"

-	"reflect"

-	"strings"

+	"net/url"

 	"testing"

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

 	"github.com/docker/docker/errdefs"

+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"

 	"gotest.tools/v3/assert"

 	is "gotest.tools/v3/assert/cmp"

 )

@@ -25,35 +24,51 @@ func TestImageSaveError(t *testing.T) {

 }

 func TestImageSave(t *testing.T) {

-	expectedURL := "/images/get"

-	client := &Client{

-		client: newMockClient(func(r *http.Request) (*http.Response, error) {

-			if !strings.HasPrefix(r.URL.Path, expectedURL) {

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

-			}

-			query := r.URL.Query()

-			names := query["names"]

-			expectedNames := []string{"image_id1", "image_id2"}

-			if !reflect.DeepEqual(names, expectedNames) {

-				return nil, fmt.Errorf("names not set in URL query properly. Expected %v, got %v", names, expectedNames)

+	const (

+		expectedURL    = "/images/get"

+		expectedOutput = "outputBody"

+	)

+	tests := []struct {

+		doc                 string

+		options             image.SaveOptions

+		expectedQueryParams url.Values

+	}{

+		{

+			doc: "no platform",

+			expectedQueryParams: url.Values{

+				"names": {"image_id1", "image_id2"},

+			},

+		},

+		{

+			doc: "platform",

+			options: image.SaveOptions{

+				Platform: &ocispec.Platform{Architecture: "arm64", OS: "linux", Variant: "v8"},

+			},

+			expectedQueryParams: url.Values{

+				"names":    {"image_id1", "image_id2"},

+				"platform": {`{"architecture":"arm64","os":"linux","variant":"v8"}`},

+			},

+		},

+	}

+	for _, tc := range tests {

+		t.Run(tc.doc, func(t *testing.T) {

+			client := &Client{

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

+					assert.Check(t, is.Equal(req.URL.Path, expectedURL))

+					assert.Check(t, is.DeepEqual(req.URL.Query(), tc.expectedQueryParams))

+					return &http.Response{

+						StatusCode: http.StatusOK,

+						Body:       io.NopCloser(bytes.NewReader([]byte(expectedOutput))),

+					}, nil

+				}),

 			}

+			resp, err := client.ImageSave(context.Background(), []string{"image_id1", "image_id2"}, tc.options)

+			assert.NilError(t, err)

+			defer assert.NilError(t, resp.Close())

-			return &http.Response{

-				StatusCode: http.StatusOK,

-				Body:       io.NopCloser(bytes.NewReader([]byte("response"))),

-			}, nil

-		}),

-	}

-	saveResponse, err := client.ImageSave(context.Background(), []string{"image_id1", "image_id2"}, image.SaveOptions{})

-	if err != nil {

-		t.Fatal(err)

-	}

-	response, err := io.ReadAll(saveResponse)

-	if err != nil {

-		t.Fatal(err)

-	}

-	saveResponse.Close()

-	if string(response) != "response" {

-		t.Fatalf("expected response to contain 'response', got %s", string(response))

+			body, err := io.ReadAll(resp)

+			assert.NilError(t, err)

+			assert.Equal(t, string(body), expectedOutput)

+		})

 	}

 }