client: reduce string-matching in tests

These checks were redundant, as we were not expecting
a specific string, just that a server-error or authentication
error was returned.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

client/checkpoint_create_test.go

@@ -23,11 +23,8 @@ func TestCheckpointCreateError(t *testing.T) {
 		Exit:         true,
 	})
 
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/checkpoint_delete_test.go

@@ -22,11 +22,8 @@ func TestCheckpointDeleteError(t *testing.T) {
 		CheckpointID: "checkpoint_id",
 	})
 
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/checkpoint_list_test.go

@@ -20,11 +20,8 @@ func TestCheckpointListError(t *testing.T) {
 	}
 
 	_, err := client.CheckpointList(context.Background(), "container_id", types.CheckpointListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/config_create_test.go

@@ -32,11 +32,8 @@ func TestConfigCreateError(t *testing.T) {
 		client:  newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ConfigCreate(context.Background(), swarm.ConfigSpec{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/config_inspect_test.go

@@ -56,11 +56,8 @@ func TestConfigInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.ConfigInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/config_list_test.go

@@ -34,11 +34,8 @@ func TestConfigListError(t *testing.T) {
 	}
 
 	_, err := client.ConfigList(context.Background(), types.ConfigListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/config_remove_test.go

@@ -30,11 +30,8 @@ func TestConfigRemoveError(t *testing.T) {
 	}
 
 	err := client.ConfigRemove(context.Background(), "config_id")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/config_update_test.go

@@ -31,11 +31,8 @@ func TestConfigUpdateError(t *testing.T) {
 	}
 
 	err := client.ConfigUpdate(context.Background(), "config_id", swarm.Version{}, swarm.ConfigSpec{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_commit_test.go

@@ -19,11 +19,8 @@ func TestContainerCommitError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerCommit(context.Background(), "nothing", types.ContainerCommitOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_copy_test.go

@@ -20,11 +20,8 @@ func TestContainerStatPathError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerStatPath(context.Background(), "container_id", "path")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -103,11 +100,8 @@ func TestCopyToContainerError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.CopyToContainer(context.Background(), "container_id", "path/to/file", bytes.NewReader([]byte("")), types.CopyToContainerOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -183,11 +177,8 @@ func TestCopyFromContainerError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, _, err := client.CopyFromContainer(context.Background(), "container_id", "path/to/file")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_create_test.go

@@ -19,9 +19,6 @@ func TestContainerCreateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerCreate(context.Background(), nil, nil, nil, "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error while testing StatusInternalServerError, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
 		t.Fatalf("expected a Server Error while testing StatusInternalServerError, got %T", err)
 	}
@@ -31,9 +28,6 @@ func TestContainerCreateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusNotFound, "Server error")),
 	}
 	_, err = client.ContainerCreate(context.Background(), nil, nil, nil, "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error while testing StatusNotFound, got %v", err)
-	}
 	if err == nil || !IsErrNotFound(err) {
 		t.Fatalf("expected a Server Error while testing StatusNotFound, got %T", err)
 	}

client/container_diff_test.go

@@ -19,11 +19,8 @@ func TestContainerDiffError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerDiff(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_exec_test.go

@@ -19,11 +19,8 @@ func TestContainerExecCreateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerExecCreate(context.Background(), "container_id", types.ExecConfig{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -77,11 +74,8 @@ func TestContainerExecStartError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerExecStart(context.Background(), "nothing", types.ExecStartCheck{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -124,11 +118,8 @@ func TestContainerExecInspectError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerExecInspect(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_export_test.go

@@ -17,11 +17,8 @@ func TestContainerExportError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerExport(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_inspect_test.go

@@ -21,11 +21,8 @@ func TestContainerInspectError(t *testing.T) {
 	}
 
 	_, err := client.ContainerInspect(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_kill_test.go

@@ -17,11 +17,8 @@ func TestContainerKillError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerKill(context.Background(), "nothing", "SIGKILL")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_list_test.go

@@ -20,11 +20,8 @@ func TestContainerListError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerList(context.Background(), types.ContainerListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_logs_test.go

@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -33,7 +34,9 @@ func TestContainerLogsError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerLogs(context.Background(), "container_id", types.ContainerLogsOptions{})
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 	_, err = client.ContainerLogs(context.Background(), "container_id", types.ContainerLogsOptions{
 		Since: "2006-01-02TZ",
 	})

client/container_pause_test.go

@@ -17,11 +17,8 @@ func TestContainerPauseError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerPause(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_prune_test.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -25,7 +26,9 @@ func TestContainersPruneError(t *testing.T) {
 	filters := filters.NewArgs()
 
 	_, err := client.ContainersPrune(context.Background(), filters)
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestContainersPrune(t *testing.T) {

client/container_remove_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -19,7 +20,9 @@ func TestContainerRemoveError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerRemove(context.Background(), "container_id", types.ContainerRemoveOptions{})
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestContainerRemoveNotFoundError(t *testing.T) {

client/container_rename_test.go

@@ -17,11 +17,8 @@ func TestContainerRenameError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerRename(context.Background(), "nothing", "newNothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_resize_test.go

@@ -18,11 +18,8 @@ func TestContainerResizeError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerResize(context.Background(), "container_id", types.ResizeOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -31,11 +28,8 @@ func TestContainerExecResizeError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerExecResize(context.Background(), "exec_id", types.ResizeOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_restart_test.go

@@ -19,11 +19,8 @@ func TestContainerRestartError(t *testing.T) {
 	}
 	timeout := 0 * time.Second
 	err := client.ContainerRestart(context.Background(), "nothing", &timeout)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_start_test.go

@@ -19,11 +19,8 @@ func TestContainerStartError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerStart(context.Background(), "nothing", types.ContainerStartOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_stats_test.go

@@ -17,11 +17,8 @@ func TestContainerStatsError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerStats(context.Background(), "nothing", false)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_stop_test.go

@@ -19,11 +19,8 @@ func TestContainerStopError(t *testing.T) {
 	}
 	timeout := 0 * time.Second
 	err := client.ContainerStop(context.Background(), "nothing", &timeout)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_top_test.go

@@ -20,11 +20,8 @@ func TestContainerTopError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerTop(context.Background(), "nothing", []string{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_unpause_test.go

@@ -17,11 +17,8 @@ func TestContainerUnpauseError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	err := client.ContainerUnpause(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_update_test.go

@@ -19,11 +19,8 @@ func TestContainerUpdateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerUpdate(context.Background(), "nothing", container.UpdateConfig{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/container_wait_test.go

@@ -25,11 +25,8 @@ func TestContainerWaitError(t *testing.T) {
 	case result := <-resultC:
 		t.Fatalf("expected to not get a wait result, got %d", result.StatusCode)
 	case err := <-errC:
-		if err.Error() != "Error response from daemon: Server error" {
-			t.Fatalf("expected a Server Error, got %v", err)
-		}
 		if !errdefs.IsSystem(err) {
-			t.Fatalf("expected a Server Error, got %T", err)
+			t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 		}
 	}
 }

client/disk_usage_test.go

@@ -19,11 +19,8 @@ func TestDiskUsageError(t *testing.T) {
 		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)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/events_test.go

@@ -53,11 +53,8 @@ func TestEventsErrorFromServer(t *testing.T) {
 	}
 	_, errs := client.Events(context.Background(), types.EventsOptions{})
 	err := <-errs
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_build_test.go

@@ -21,11 +21,8 @@ func TestImageBuildError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageBuild(context.Background(), nil, types.ImageBuildOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_create_test.go

@@ -18,11 +18,8 @@ func TestImageCreateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageCreate(context.Background(), "reference", types.ImageCreateOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_history_test.go

@@ -19,11 +19,8 @@ func TestImageHistoryError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageHistory(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_import_test.go

@@ -19,11 +19,8 @@ func TestImageImportError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageImport(context.Background(), types.ImageImportSource{}, "image:tag", types.ImageImportOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_inspect_test.go

@@ -22,11 +22,8 @@ func TestImageInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.ImageInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_list_test.go

@@ -21,11 +21,8 @@ func TestImageListError(t *testing.T) {
 	}
 
 	_, err := client.ImageList(context.Background(), types.ImageListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_load_test.go

@@ -18,11 +18,8 @@ func TestImageLoadError(t *testing.T) {
 	}
 
 	_, err := client.ImageLoad(context.Background(), nil, true)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_prune_test.go

@@ -10,6 +10,8 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/docker/docker/errdefs"
+
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
 	"gotest.tools/assert"
@@ -22,10 +24,10 @@ func TestImagesPruneError(t *testing.T) {
 		version: "1.25",
 	}
 
-	filters := filters.NewArgs()
-
-	_, err := client.ImagesPrune(context.Background(), filters)
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	_, err := client.ImagesPrune(context.Background(), filters.NewArgs())
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestImagesPrune(t *testing.T) {

client/image_pull_test.go

@@ -31,11 +31,8 @@ func TestImagePullAnyError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImagePull(context.Background(), "myimage", types.ImagePullOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -44,8 +41,8 @@ func TestImagePullStatusUnauthorizedError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusUnauthorized, "Unauthorized error")),
 	}
 	_, err := client.ImagePull(context.Background(), "myimage", types.ImagePullOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -74,8 +71,8 @@ func TestImagePullWithUnauthorizedErrorAndAnotherUnauthorizedError(t *testing.T)
 	_, err := client.ImagePull(context.Background(), "myimage", types.ImagePullOptions{
 		PrivilegeFunc: privilegeFunc,
 	})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_push_test.go

@@ -36,11 +36,8 @@ func TestImagePushAnyError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImagePush(context.Background(), "myimage", types.ImagePushOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -49,8 +46,8 @@ func TestImagePushStatusUnauthorizedError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusUnauthorized, "Unauthorized error")),
 	}
 	_, err := client.ImagePush(context.Background(), "myimage", types.ImagePushOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -79,8 +76,8 @@ func TestImagePushWithUnauthorizedErrorAndAnotherUnauthorizedError(t *testing.T)
 	_, err := client.ImagePush(context.Background(), "myimage", types.ImagePushOptions{
 		PrivilegeFunc: privilegeFunc,
 	})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_remove_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -21,7 +22,9 @@ func TestImageRemoveError(t *testing.T) {
 	}
 
 	_, err := client.ImageRemove(context.Background(), "image_id", types.ImageRemoveOptions{})
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestImageRemoveImageNotFound(t *testing.T) {

client/image_save_test.go

@@ -18,11 +18,8 @@ func TestImageSaveError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageSave(context.Background(), []string{"nothing"})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_search_test.go

@@ -21,11 +21,8 @@ func TestImageSearchAnyError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ImageSearch(context.Background(), "some-image", types.ImageSearchOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -34,8 +31,8 @@ func TestImageSearchStatusUnauthorizedError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusUnauthorized, "Unauthorized error")),
 	}
 	_, err := client.ImageSearch(context.Background(), "some-image", types.ImageSearchOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 
@@ -64,8 +61,8 @@ func TestImageSearchWithUnauthorizedErrorAndAnotherUnauthorizedError(t *testing.
 	_, err := client.ImageSearch(context.Background(), "some-image", types.ImageSearchOptions{
 		PrivilegeFunc: privilegeFunc,
 	})
-	if err == nil || err.Error() != "Error response from daemon: Unauthorized error" {
-		t.Fatalf("expected an Unauthorized Error, got %v", err)
+	if !errdefs.IsUnauthorized(err) {
+		t.Fatalf("expected a Unauthorized Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/image_tag_test.go

@@ -18,11 +18,8 @@ func TestImageTagError(t *testing.T) {
 	}
 
 	err := client.ImageTag(context.Background(), "image_id", "repo:tag")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/info_test.go

@@ -19,11 +19,8 @@ func TestInfoServerError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.Info(context.Background())
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_connect_test.go

@@ -21,11 +21,8 @@ func TestNetworkConnectError(t *testing.T) {
 	}
 
 	err := client.NetworkConnect(context.Background(), "network_id", "container_id", nil)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_create_test.go

@@ -20,11 +20,8 @@ func TestNetworkCreateError(t *testing.T) {
 	}
 
 	_, err := client.NetworkCreate(context.Background(), "mynetwork", types.NetworkCreate{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_disconnect_test.go

@@ -20,11 +20,8 @@ func TestNetworkDisconnectError(t *testing.T) {
 	}
 
 	err := client.NetworkDisconnect(context.Background(), "network_id", "container_id", false)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_inspect_test.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/network"
+	"github.com/docker/docker/errdefs"
 	"github.com/pkg/errors"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
@@ -23,7 +24,9 @@ func TestNetworkInspectError(t *testing.T) {
 	}
 
 	_, err := client.NetworkInspect(context.Background(), "nothing", types.NetworkInspectOptions{})
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestNetworkInspectNotFoundError(t *testing.T) {

client/network_list_test.go

@@ -23,11 +23,8 @@ func TestNetworkListError(t *testing.T) {
 	_, err := client.NetworkList(context.Background(), types.NetworkListOptions{
 		Filters: filters.NewArgs(),
 	})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_prune_test.go

@@ -26,11 +26,8 @@ func TestNetworksPruneError(t *testing.T) {
 	filters := filters.NewArgs()
 
 	_, err := client.NetworksPrune(context.Background(), filters)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/network_remove_test.go

@@ -18,11 +18,8 @@ func TestNetworkRemoveError(t *testing.T) {
 	}
 
 	err := client.NetworkRemove(context.Background(), "network_id")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/node_inspect_test.go

@@ -21,11 +21,8 @@ func TestNodeInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.NodeInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/node_list_test.go

@@ -22,11 +22,8 @@ func TestNodeListError(t *testing.T) {
 	}
 
 	_, err := client.NodeList(context.Background(), types.NodeListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/node_remove_test.go

@@ -19,11 +19,8 @@ func TestNodeRemoveError(t *testing.T) {
 	}
 
 	err := client.NodeRemove(context.Background(), "node_id", types.NodeRemoveOptions{Force: false})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/node_update_test.go

@@ -19,11 +19,8 @@ func TestNodeUpdateError(t *testing.T) {
 	}
 
 	err := client.NodeUpdate(context.Background(), "node_id", swarm.Version{}, swarm.NodeSpec{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_disable_test.go

@@ -19,11 +19,8 @@ func TestPluginDisableError(t *testing.T) {
 	}
 
 	err := client.PluginDisable(context.Background(), "plugin_name", types.PluginDisableOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_enable_test.go

@@ -19,11 +19,8 @@ func TestPluginEnableError(t *testing.T) {
 	}
 
 	err := client.PluginEnable(context.Background(), "plugin_name", types.PluginEnableOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_inspect_test.go

@@ -21,11 +21,8 @@ func TestPluginInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.PluginInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_list_test.go

@@ -21,11 +21,8 @@ func TestPluginListError(t *testing.T) {
 	}
 
 	_, err := client.PluginList(context.Background(), filters.NewArgs())
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_push_test.go

@@ -18,11 +18,8 @@ func TestPluginPushError(t *testing.T) {
 	}
 
 	_, err := client.PluginPush(context.Background(), "plugin_name", "")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_remove_test.go

@@ -19,11 +19,8 @@ func TestPluginRemoveError(t *testing.T) {
 	}
 
 	err := client.PluginRemove(context.Background(), "plugin_name", types.PluginRemoveOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/plugin_set_test.go

@@ -18,11 +18,8 @@ func TestPluginSetError(t *testing.T) {
 	}
 
 	err := client.PluginSet(context.Background(), "plugin_name", []string{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/request_test.go

@@ -86,11 +86,8 @@ func TestPlainTextError(t *testing.T) {
 		client: newMockClient(plainTextErrorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ContainerList(context.Background(), types.ContainerListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/secret_create_test.go

@@ -32,11 +32,8 @@ func TestSecretCreateError(t *testing.T) {
 		client:  newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.SecretCreate(context.Background(), swarm.SecretSpec{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/secret_inspect_test.go

@@ -33,11 +33,8 @@ func TestSecretInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.SecretInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/secret_list_test.go

@@ -34,11 +34,8 @@ func TestSecretListError(t *testing.T) {
 	}
 
 	_, err := client.SecretList(context.Background(), types.SecretListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/secret_remove_test.go

@@ -30,11 +30,8 @@ func TestSecretRemoveError(t *testing.T) {
 	}
 
 	err := client.SecretRemove(context.Background(), "secret_id")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/secret_update_test.go

@@ -31,11 +31,8 @@ func TestSecretUpdateError(t *testing.T) {
 	}
 
 	err := client.SecretUpdate(context.Background(), "secret_id", swarm.Version{}, swarm.SecretSpec{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/service_create_test.go

@@ -25,11 +25,8 @@ func TestServiceCreateError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ServiceCreate(context.Background(), swarm.ServiceSpec{}, types.ServiceCreateOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/service_inspect_test.go

@@ -22,11 +22,8 @@ func TestServiceInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.ServiceInspectWithRaw(context.Background(), "nothing", types.ServiceInspectOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/service_list_test.go

@@ -22,11 +22,8 @@ func TestServiceListError(t *testing.T) {
 	}
 
 	_, err := client.ServiceList(context.Background(), types.ServiceListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/service_logs_test.go

@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -23,7 +24,9 @@ func TestServiceLogsError(t *testing.T) {
 		client: newMockClient(errorMock(http.StatusInternalServerError, "Server error")),
 	}
 	_, err := client.ServiceLogs(context.Background(), "service_id", types.ContainerLogsOptions{})
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 	_, err = client.ServiceLogs(context.Background(), "service_id", types.ContainerLogsOptions{
 		Since: "2006-01-02TZ",
 	})

client/service_remove_test.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -19,7 +20,9 @@ func TestServiceRemoveError(t *testing.T) {
 	}
 
 	err := client.ServiceRemove(context.Background(), "service_id")
-	assert.Check(t, is.Error(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestServiceRemoveNotFoundError(t *testing.T) {

client/service_update_test.go

@@ -20,11 +20,8 @@ func TestServiceUpdateError(t *testing.T) {
 	}
 
 	_, err := client.ServiceUpdate(context.Background(), "service_id", swarm.Version{}, swarm.ServiceSpec{}, types.ServiceUpdateOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_get_unlock_key_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
 )
@@ -21,7 +22,9 @@ func TestSwarmGetUnlockKeyError(t *testing.T) {
 	}
 
 	_, err := client.SwarmGetUnlockKey(context.Background())
-	assert.Check(t, is.ErrorContains(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestSwarmGetUnlockKey(t *testing.T) {

client/swarm_init_test.go

@@ -19,11 +19,8 @@ func TestSwarmInitError(t *testing.T) {
 	}
 
 	_, err := client.SwarmInit(context.Background(), swarm.InitRequest{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_inspect_test.go

@@ -20,11 +20,8 @@ func TestSwarmInspectError(t *testing.T) {
 	}
 
 	_, err := client.SwarmInspect(context.Background())
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_join_test.go

@@ -19,11 +19,8 @@ func TestSwarmJoinError(t *testing.T) {
 	}
 
 	err := client.SwarmJoin(context.Background(), swarm.JoinRequest{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_leave_test.go

@@ -18,11 +18,8 @@ func TestSwarmLeaveError(t *testing.T) {
 	}
 
 	err := client.SwarmLeave(context.Background(), false)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_unlock_test.go

@@ -19,11 +19,8 @@ func TestSwarmUnlockError(t *testing.T) {
 	}
 
 	err := client.SwarmUnlock(context.Background(), swarm.UnlockRequest{UnlockKey: "SWMKEY-1-y6guTZNTwpQeTL5RhUfOsdBdXoQjiB2GADHSRJvbXeU"})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/swarm_update_test.go

@@ -19,11 +19,8 @@ func TestSwarmUpdateError(t *testing.T) {
 	}
 
 	err := client.SwarmUpdate(context.Background(), swarm.Version{}, swarm.Spec{}, swarm.UpdateFlags{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/task_inspect_test.go

@@ -21,11 +21,8 @@ func TestTaskInspectError(t *testing.T) {
 	}
 
 	_, _, err := client.TaskInspectWithRaw(context.Background(), "nothing")
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/task_list_test.go

@@ -22,11 +22,8 @@ func TestTaskListError(t *testing.T) {
 	}
 
 	_, err := client.TaskList(context.Background(), types.TaskListOptions{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/volume_create_test.go

@@ -21,11 +21,8 @@ func TestVolumeCreateError(t *testing.T) {
 	}
 
 	_, err := client.VolumeCreate(context.Background(), volumetypes.VolumeCreateBody{})
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/volume_inspect_test.go

@@ -11,6 +11,7 @@ import (
 	"testing"
 
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/errdefs"
 	"github.com/pkg/errors"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
@@ -22,7 +23,9 @@ func TestVolumeInspectError(t *testing.T) {
 	}
 
 	_, err := client.VolumeInspect(context.Background(), "nothing")
-	assert.Check(t, is.ErrorContains(err, "Error response from daemon: Server error"))
+	if !errdefs.IsSystem(err) {
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
+	}
 }
 
 func TestVolumeInspectNotFound(t *testing.T) {

client/volume_list_test.go

@@ -22,11 +22,8 @@ func TestVolumeListError(t *testing.T) {
 	}
 
 	_, err := client.VolumeList(context.Background(), filters.NewArgs())
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }
 

client/volume_remove_test.go

@@ -18,11 +18,8 @@ func TestVolumeRemoveError(t *testing.T) {
 	}
 
 	err := client.VolumeRemove(context.Background(), "volume_id", false)
-	if err == nil || err.Error() != "Error response from daemon: Server error" {
-		t.Fatalf("expected a Server Error, got %v", err)
-	}
 	if !errdefs.IsSystem(err) {
-		t.Fatalf("expected a Server Error, got %T", err)
+		t.Fatalf("expected a Server Error, got %[1]T: %[1]v", err)
 	}
 }