integration-cli/TestSaveAndLoadRepoFlags: Ignore LastTagTime difference

The reason it doesn't change with the graphdrivers is caused by an
implementation detail and the fact that the image is loaded into the
same daemon it was saved from.

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

integration-cli/docker_cli_save_load_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"os"
 	"os/exec"
@@ -9,8 +10,10 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/integration-cli/cli/build"
 	"gotest.tools/v3/assert"
+	is "gotest.tools/v3/assert/cmp"
 	"gotest.tools/v3/icmd"
 )
 
@@ -149,15 +152,39 @@ func (s *DockerCLISaveLoadSuite) TestSaveAndLoadRepoFlags(c *testing.T) {
 	deleteImages(repoName)
 	dockerCmd(c, "commit", name, repoName)
 
-	before, _ := dockerCmd(c, "inspect", repoName)
+	beforeStr, _, err := dockerCmdWithError("inspect", repoName)
+	assert.NilError(c, err, "failed to inspect before save")
 
 	out, err := RunCommandPipelineWithOutput(
 		exec.Command(dockerBinary, "save", repoName),
 		exec.Command(dockerBinary, "load"))
 	assert.NilError(c, err, "failed to save and load repo: %s, %v", out, err)
 
-	after, _ := dockerCmd(c, "inspect", repoName)
-	assert.Equal(c, before, after, "inspect is not the same after a save / load")
+	afterStr, _, err := dockerCmdWithError("inspect", repoName)
+	assert.NilError(c, err, "failed to inspect after load")
+
+	var before, after []types.ImageInspect
+	err = json.Unmarshal([]byte(beforeStr), &before)
+	assert.NilError(c, err, "failed to parse inspect 'before' output")
+	err = json.Unmarshal([]byte(afterStr), &after)
+	assert.NilError(c, err, "failed to parse inspect 'after' output")
+
+	assert.Assert(c, is.Len(before, 1))
+	assert.Assert(c, is.Len(after, 1))
+
+	if testEnv.UsingSnapshotter() {
+		// Ignore LastTagTime difference with c8d.
+		// It is not stored in the image archive, but in the imageStore
+		// which is a graphdrivers implementation detail.
+		//
+		// It works because we load the image into the same daemon which saved
+		// the image. It would still fail with the graphdrivers if the image
+		// was loaded into a different daemon (which should be the case in a
+		// real-world scenario).
+		before[0].Metadata.LastTagTime = after[0].Metadata.LastTagTime
+	}
+
+	assert.Check(c, is.DeepEqual(before, after), "inspect is not the same after a save / load")
 }
 
 func (s *DockerCLISaveLoadSuite) TestSaveWithNoExistImage(c *testing.T) {