Fix ineffassign linting

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

integration-cli/docker_api_containers_test.go

@@ -1265,6 +1265,7 @@ func (s *DockerSuite) TestContainerAPIDeleteRemoveVolume(c *check.C) {
 	c.Assert(waitRun(id), checker.IsNil)
 
 	source, err := inspectMountSourceField(id, vol)
+	c.Assert(err, checker.IsNil)
 	_, err = os.Stat(source)
 	c.Assert(err, checker.IsNil)
 
@@ -2201,6 +2202,7 @@ func (s *DockerSuite) TestContainerKillCustomStopSignal(c *check.C) {
 	defer res.Body.Close()
 
 	b, err := ioutil.ReadAll(res.Body)
+	c.Assert(err, checker.IsNil)
 	c.Assert(res.StatusCode, checker.Equals, http.StatusNoContent, check.Commentf(string(b)))
 	err = waitInspect(id, "{{.State.Running}} {{.State.Restarting}}", "false false", 30*time.Second)
 	c.Assert(err, checker.IsNil)

integration-cli/docker_cli_build_test.go

@@ -1012,10 +1012,6 @@ func (s *DockerSuite) TestBuildAddBadLinksVolume(c *check.C) {
 		ADD foo.txt /x/`
 		targetFile = "foo.txt"
 	)
-	var (
-		name       = "test-link-absolute-volume"
-		dockerfile = ""
-	)
 
 	tempDir, err := ioutil.TempDir("", "test-link-absolute-volume-temp-")
 	if err != nil {
@@ -1023,7 +1019,7 @@ func (s *DockerSuite) TestBuildAddBadLinksVolume(c *check.C) {
 	}
 	defer os.RemoveAll(tempDir)
 
-	dockerfile = fmt.Sprintf(dockerfileTemplate, tempDir)
+	dockerfile := fmt.Sprintf(dockerfileTemplate, tempDir)
 	nonExistingFile := filepath.Join(tempDir, targetFile)
 
 	ctx := fakecontext.New(c, "", fakecontext.WithDockerfile(dockerfile))
@@ -1040,7 +1036,7 @@ func (s *DockerSuite) TestBuildAddBadLinksVolume(c *check.C) {
 		c.Fatal(err)
 	}
 
-	buildImageSuccessfully(c, name, build.WithExternalBuildContext(ctx))
+	buildImageSuccessfully(c, "test-link-absolute-volume", build.WithExternalBuildContext(ctx))
 	if _, err := os.Stat(nonExistingFile); err == nil || err != nil && !os.IsNotExist(err) {
 		c.Fatalf("%s shouldn't have been written and it shouldn't exist", nonExistingFile)
 	}

integration-cli/docker_cli_commit_test.go

@@ -46,8 +46,7 @@ func (s *DockerSuite) TestCommitPausedContainer(c *check.C) {
 	cleanedContainerID := strings.TrimSpace(out)
 
 	dockerCmd(c, "pause", cleanedContainerID)
-
+	dockerCmd(c, "commit", cleanedContainerID)
-	out, _ = dockerCmd(c, "commit", cleanedContainerID)
 
 	out = inspectField(c, cleanedContainerID, "State.Paused")
 	// commit should not unpause a paused container

integration-cli/docker_cli_config_create_test.go

@@ -78,6 +78,7 @@ func (s *DockerSwarmSuite) TestConfigCreateResolve(c *check.C) {
 	c.Assert(out, checker.Contains, fake)
 
 	out, err = d.Cmd("config", "rm", id)
+	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Contains, id)
 
 	// Fake one will remain
@@ -93,6 +94,7 @@ func (s *DockerSwarmSuite) TestConfigCreateResolve(c *check.C) {
 	// - Full Name
 	// - Partial ID (prefix)
 	out, err = d.Cmd("config", "rm", id[:5])
+	c.Assert(err, checker.Not(checker.IsNil))
 	c.Assert(out, checker.Not(checker.Contains), id)
 	out, err = d.Cmd("config", "ls")
 	c.Assert(err, checker.IsNil)
@@ -101,6 +103,7 @@ func (s *DockerSwarmSuite) TestConfigCreateResolve(c *check.C) {
 
 	// Remove based on ID prefix of the fake one should succeed
 	out, err = d.Cmd("config", "rm", fake[:5])
+	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Contains, fake[:5])
 	out, err = d.Cmd("config", "ls")
 	c.Assert(err, checker.IsNil)

integration-cli/docker_cli_cp_test.go

@@ -423,6 +423,7 @@ func (s *DockerSuite) TestCpSpecialFiles(c *check.C) {
 
 	expected := readContainerFile(c, containerID, "resolv.conf")
 	actual, err := ioutil.ReadFile(outDir + "/resolv.conf")
+	c.Assert(err, checker.IsNil)
 
 	// Expected copied file to be duplicate of the container resolvconf
 	c.Assert(bytes.Equal(actual, expected), checker.True)
@@ -432,6 +433,7 @@ func (s *DockerSuite) TestCpSpecialFiles(c *check.C) {
 
 	expected = readContainerFile(c, containerID, "hosts")
 	actual, err = ioutil.ReadFile(outDir + "/hosts")
+	c.Assert(err, checker.IsNil)
 
 	// Expected copied file to be duplicate of the container hosts
 	c.Assert(bytes.Equal(actual, expected), checker.True)
@@ -639,6 +641,7 @@ func (s *DockerSuite) TestCpSymlinkFromConToHostFollowSymlink(c *check.C) {
 
 	expected := []byte(cpContainerContents)
 	actual, err := ioutil.ReadFile(expectedPath)
+	c.Assert(err, checker.IsNil)
 
 	if !bytes.Equal(actual, expected) {
 		c.Fatalf("Expected copied file to be duplicate of the container symbol link target")

integration-cli/docker_cli_daemon_test.go

@@ -448,10 +448,10 @@ func (s *DockerDaemonSuite) TestDaemonIPv6FixedCIDRAndMac(c *check.C) {
 
 	s.d.StartWithBusybox(c, "--ipv6", "--fixed-cidr-v6=2001:db8:1::/64")
 
-	out, err := s.d.Cmd("run", "-itd", "--name=ipv6test", "--mac-address", "AA:BB:CC:DD:EE:FF", "busybox")
+	_, err := s.d.Cmd("run", "-itd", "--name=ipv6test", "--mac-address", "AA:BB:CC:DD:EE:FF", "busybox")
 	c.Assert(err, checker.IsNil)
 
-	out, err = s.d.Cmd("inspect", "--format", "{{.NetworkSettings.Networks.bridge.GlobalIPv6Address}}", "ipv6test")
+	out, err := s.d.Cmd("inspect", "--format", "{{.NetworkSettings.Networks.bridge.GlobalIPv6Address}}", "ipv6test")
 	c.Assert(err, checker.IsNil)
 	c.Assert(strings.Trim(out, " \r\n'"), checker.Equals, "2001:db8:1::aabb:ccdd:eeff")
 }
@@ -742,6 +742,7 @@ func (s *DockerDaemonSuite) TestDaemonBridgeFixedCidr2(c *check.C) {
 	defer d.Cmd("stop", "bb")
 
 	out, err = d.Cmd("exec", "bb", "/bin/sh", "-c", "ifconfig eth0 | awk '/inet addr/{print substr($2,6)}'")
+	c.Assert(err, check.IsNil)
 	c.Assert(out, checker.Equals, "10.2.2.0\n")
 
 	out, err = d.Cmd("run", "--rm", "busybox", "/bin/sh", "-c", "ifconfig eth0 | awk '/inet addr/{print substr($2,6)}'")
@@ -1944,11 +1945,12 @@ func (s *DockerDaemonSuite) TestDaemonRestartWithNames(c *check.C) {
 	test2ID := strings.TrimSpace(out)
 
 	out, err = s.d.Cmd("run", "-d", "--name=test3", "--link", "test2:abc", "busybox", "top")
+	c.Assert(err, check.IsNil)
 	test3ID := strings.TrimSpace(out)
 
 	s.d.Restart(c)
 
-	out, err = s.d.Cmd("create", "--name=test", "busybox")
+	_, err = s.d.Cmd("create", "--name=test", "busybox")
 	c.Assert(err, check.NotNil, check.Commentf("expected error trying to create container with duplicate name"))
 	// this one is no longer needed, removing simplifies the remainder of the test
 	out, err = s.d.Cmd("rm", "-f", "test")
@@ -2615,6 +2617,7 @@ func (s *DockerDaemonSuite) TestDaemonRestartWithAutoRemoveContainer(c *check.C)
 	c.Assert(err, checker.IsNil, check.Commentf("run top2: %v", out))
 
 	out, err = s.d.Cmd("ps")
+	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Contains, "top1", check.Commentf("top1 should be running"))
 	c.Assert(out, checker.Contains, "top2", check.Commentf("top2 should be running"))
 
@@ -2639,11 +2642,11 @@ func (s *DockerDaemonSuite) TestDaemonRestartSaveContainerExitCode(c *check.C) {
 	// captured, so `.State.Error` is empty.
 	// See the discussion on https://github.com/docker/docker/pull/30227#issuecomment-274161426,
 	// and https://github.com/docker/docker/pull/26061#r78054578 for more information.
-	out, err := s.d.Cmd("run", "--name", containerName, "--init=false", "busybox", "toto")
+	_, err := s.d.Cmd("run", "--name", containerName, "--init=false", "busybox", "toto")
 	c.Assert(err, checker.NotNil)
 
 	// Check that those values were saved on disk
-	out, err = s.d.Cmd("inspect", "-f", "{{.State.ExitCode}}", containerName)
+	out, err := s.d.Cmd("inspect", "-f", "{{.State.ExitCode}}", containerName)
 	out = strings.TrimSpace(out)
 	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Equals, "127")

integration-cli/docker_cli_health_test.go

@@ -81,7 +81,7 @@ func (s *DockerSuite) TestHealth(c *check.C) {
 	dockerCmd(c, "rm", "-f", name)
 
 	// Disable the check from the CLI
-	out, _ = dockerCmd(c, "create", "--name=noh", "--no-healthcheck", imageName)
+	dockerCmd(c, "create", "--name=noh", "--no-healthcheck", imageName)
 	out, _ = dockerCmd(c, "inspect", "--format={{.Config.Healthcheck.Test}}", "noh")
 	c.Check(out, checker.Equals, "[NONE]\n")
 	dockerCmd(c, "rm", "noh")

integration-cli/docker_cli_logs_test.go

@@ -181,14 +181,14 @@ func (s *DockerSuite) TestLogsSinceFutureFollow(c *check.C) {
 	// TODO Windows TP5 - Figure out why this test is so flakey. Disabled for now.
 	testRequires(c, DaemonIsLinux)
 	name := "testlogssincefuturefollow"
-	out, _ := dockerCmd(c, "run", "-d", "--name", name, "busybox", "/bin/sh", "-c", `for i in $(seq 1 5); do echo log$i; sleep 1; done`)
+	dockerCmd(c, "run", "-d", "--name", name, "busybox", "/bin/sh", "-c", `for i in $(seq 1 5); do echo log$i; sleep 1; done`)
 
 	// Extract one timestamp from the log file to give us a starting point for
 	// our `--since` argument. Because the log producer runs in the background,
 	// we need to check repeatedly for some output to be produced.
 	var timestamp string
 	for i := 0; i != 100 && timestamp == ""; i++ {
-		if out, _ = dockerCmd(c, "logs", "-t", name); out == "" {
+		if out, _ := dockerCmd(c, "logs", "-t", name); out == "" {
 			time.Sleep(time.Millisecond * 100) // Retry
 		} else {
 			timestamp = strings.Split(strings.Split(out, "\n")[0], " ")[0]
@@ -200,7 +200,7 @@ func (s *DockerSuite) TestLogsSinceFutureFollow(c *check.C) {
 	c.Assert(err, check.IsNil)
 
 	since := t.Unix() + 2
-	out, _ = dockerCmd(c, "logs", "-t", "-f", fmt.Sprintf("--since=%v", since), name)
+	out, _ := dockerCmd(c, "logs", "-t", "-f", fmt.Sprintf("--since=%v", since), name)
 	c.Assert(out, checker.Not(checker.HasLen), 0, check.Commentf("cannot read from empty log"))
 	lines := strings.Split(strings.TrimSpace(out), "\n")
 	for _, v := range lines {

integration-cli/docker_cli_network_unix_test.go

@@ -348,7 +348,7 @@ func (s *DockerNetworkSuite) TestDockerNetworkLsFilter(c *check.C) {
 	out, _ = dockerCmd(c, "network", "ls", "-f", "type=custom", "-f", "type=builtin")
 	assertNwList(c, out, []string{"bridge", "dev", "host", "none"})
 
-	out, _ = dockerCmd(c, "network", "create", "--label", testLabel+"="+testValue, testNet)
+	dockerCmd(c, "network", "create", "--label", testLabel+"="+testValue, testNet)
 	assertNwIsAvailable(c, testNet)
 
 	out, _ = dockerCmd(c, "network", "ls", "-f", "label="+testLabel)
@@ -880,8 +880,6 @@ func (s *DockerNetworkSuite) TestDockerNetworkAnonymousEndpoint(c *check.C) {
 	out, _ = dockerCmd(c, "run", "-d", "--net", cstmBridgeNw, "busybox", "top")
 	cid2 := strings.TrimSpace(out)
 
-	hosts2 := readContainerFileWithExec(c, cid2, hostsFile)
-
 	// verify first container etc/hosts file has not changed
 	hosts1post := readContainerFileWithExec(c, cid1, hostsFile)
 	c.Assert(string(hosts1), checker.Equals, string(hosts1post),
@@ -894,7 +892,7 @@ func (s *DockerNetworkSuite) TestDockerNetworkAnonymousEndpoint(c *check.C) {
 
 	dockerCmd(c, "network", "connect", cstmBridgeNw1, cid2)
 
-	hosts2 = readContainerFileWithExec(c, cid2, hostsFile)
+	hosts2 := readContainerFileWithExec(c, cid2, hostsFile)
 	hosts1post = readContainerFileWithExec(c, cid1, hostsFile)
 	c.Assert(string(hosts1), checker.Equals, string(hosts1post),
 		check.Commentf("Unexpected %s change on container connect", hostsFile))

integration-cli/docker_cli_plugins_test.go

@@ -62,10 +62,10 @@ func (ps *DockerPluginSuite) TestPluginBasicOps(c *check.C) {
 func (ps *DockerPluginSuite) TestPluginForceRemove(c *check.C) {
 	pNameWithTag := ps.getPluginRepoWithTag()
 
-	out, _, err := dockerCmdWithError("plugin", "install", "--grant-all-permissions", pNameWithTag)
+	_, _, err := dockerCmdWithError("plugin", "install", "--grant-all-permissions", pNameWithTag)
 	c.Assert(err, checker.IsNil)
 
-	out, _, err = dockerCmdWithError("plugin", "remove", pNameWithTag)
+	out, _, _ := dockerCmdWithError("plugin", "remove", pNameWithTag)
 	c.Assert(out, checker.Contains, "is enabled")
 
 	out, _, err = dockerCmdWithError("plugin", "remove", "--force", pNameWithTag)
@@ -82,7 +82,7 @@ func (s *DockerSuite) TestPluginActive(c *check.C) {
 	_, _, err = dockerCmdWithError("volume", "create", "-d", pNameWithTag, "--name", "testvol1")
 	c.Assert(err, checker.IsNil)
 
-	out, _, err := dockerCmdWithError("plugin", "disable", pNameWithTag)
+	out, _, _ := dockerCmdWithError("plugin", "disable", pNameWithTag)
 	c.Assert(out, checker.Contains, "in use")
 
 	_, _, err = dockerCmdWithError("volume", "rm", "testvol1")
@@ -98,21 +98,21 @@ func (s *DockerSuite) TestPluginActive(c *check.C) {
 
 func (s *DockerSuite) TestPluginActiveNetwork(c *check.C) {
 	testRequires(c, DaemonIsLinux, IsAmd64, Network)
-	out, _, err := dockerCmdWithError("plugin", "install", "--grant-all-permissions", npNameWithTag)
+	_, _, err := dockerCmdWithError("plugin", "install", "--grant-all-permissions", npNameWithTag)
 	c.Assert(err, checker.IsNil)
 
-	out, _, err = dockerCmdWithError("network", "create", "-d", npNameWithTag, "test")
+	out, _, err := dockerCmdWithError("network", "create", "-d", npNameWithTag, "test")
 	c.Assert(err, checker.IsNil)
 
 	nID := strings.TrimSpace(out)
 
-	out, _, err = dockerCmdWithError("plugin", "remove", npNameWithTag)
+	out, _, _ = dockerCmdWithError("plugin", "remove", npNameWithTag)
 	c.Assert(out, checker.Contains, "is in use")
 
 	_, _, err = dockerCmdWithError("network", "rm", nID)
 	c.Assert(err, checker.IsNil)
 
-	out, _, err = dockerCmdWithError("plugin", "remove", npNameWithTag)
+	out, _, _ = dockerCmdWithError("plugin", "remove", npNameWithTag)
 	c.Assert(out, checker.Contains, "is enabled")
 
 	_, _, err = dockerCmdWithError("plugin", "disable", npNameWithTag)
@@ -400,7 +400,7 @@ func (ps *DockerPluginSuite) TestPluginIDPrefix(c *check.C) {
 	c.Assert(out, checker.Contains, "false")
 
 	// Remove
-	out, _, err = dockerCmdWithError("plugin", "remove", id[:5])
+	_, _, err = dockerCmdWithError("plugin", "remove", id[:5])
 	c.Assert(err, checker.IsNil)
 	// List returns none
 	out, _, err = dockerCmdWithError("plugin", "ls")

integration-cli/docker_cli_ps_test.go

@@ -792,19 +792,14 @@ func (s *DockerSuite) TestPsListContainersFilterNetwork(c *check.C) {
 }
 
 func (s *DockerSuite) TestPsByOrder(c *check.C) {
-	name1 := "xyz-abc"
+	out := runSleepingContainer(c, "--name", "xyz-abc")
-	out := runSleepingContainer(c, "--name", name1)
 	container1 := strings.TrimSpace(out)
 
-	name2 := "xyz-123"
+	out = runSleepingContainer(c, "--name", "xyz-123")
-	out = runSleepingContainer(c, "--name", name2)
 	container2 := strings.TrimSpace(out)
 
-	name3 := "789-abc"
+	runSleepingContainer(c, "--name", "789-abc")
-	out = runSleepingContainer(c, "--name", name3)
+	runSleepingContainer(c, "--name", "789-123")
-
-	name4 := "789-123"
-	out = runSleepingContainer(c, "--name", name4)
 
 	// Run multiple time should have the same result
 	out = cli.DockerCmd(c, "ps", "--no-trunc", "-q", "-f", "name=xyz").Combined()

integration-cli/docker_cli_restart_test.go

@@ -224,6 +224,7 @@ func (s *DockerSuite) TestRestartWithPolicyUserDefinedNetwork(c *check.C) {
 	c.Assert(err, check.IsNil)
 
 	err = waitInspect("second", "{{.State.Status}}", "running", 5*time.Second)
+	c.Assert(err, check.IsNil)
 
 	// ping to first and its alias foo must still succeed
 	_, _, err = dockerCmdWithError("exec", "second", "ping", "-c", "1", "first")

integration-cli/docker_cli_run_test.go

@@ -623,6 +623,7 @@ func (s *DockerSuite) TestRunCreateVolumeWithSymlink(c *check.C) {
 	// Cannot run on Windows as relies on Linux-specific functionality (sh -c mount...)
 	testRequires(c, DaemonIsLinux)
 	workingDirectory, err := ioutil.TempDir("", "TestRunCreateVolumeWithSymlink")
+	c.Assert(err, checker.IsNil)
 	image := "docker-test-createvolumewithsymlink"
 
 	buildCmd := exec.Command(dockerBinary, "build", "-t", image, "-")

integration-cli/docker_cli_secret_create_test.go

@@ -39,6 +39,7 @@ func (s *DockerSwarmSuite) TestSecretCreateResolve(c *check.C) {
 	c.Assert(out, checker.Contains, fake)
 
 	out, err = d.Cmd("secret", "rm", id)
+	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Contains, id)
 
 	// Fake one will remain
@@ -54,6 +55,7 @@ func (s *DockerSwarmSuite) TestSecretCreateResolve(c *check.C) {
 	// - Full Name
 	// - Partial ID (prefix)
 	out, err = d.Cmd("secret", "rm", id[:5])
+	c.Assert(err, checker.Not(checker.IsNil))
 	c.Assert(out, checker.Not(checker.Contains), id)
 	out, err = d.Cmd("secret", "ls")
 	c.Assert(err, checker.IsNil)
@@ -62,6 +64,7 @@ func (s *DockerSwarmSuite) TestSecretCreateResolve(c *check.C) {
 
 	// Remove based on ID prefix of the fake one should succeed
 	out, err = d.Cmd("secret", "rm", fake[:5])
+	c.Assert(err, checker.IsNil)
 	c.Assert(out, checker.Contains, fake[:5])
 	out, err = d.Cmd("secret", "ls")
 	c.Assert(err, checker.IsNil)

integration-cli/docker_cli_service_scale_test.go

@@ -21,16 +21,16 @@ func (s *DockerSwarmSuite) TestServiceScale(c *check.C) {
 	service2Args := append([]string{"service", "create", "--detach", "--no-resolve-image", "--name", service2Name, "--mode=global", defaultSleepImage}, sleepCommandForDaemonPlatform()...)
 
 	// Create services
-	out, err := d.Cmd(service1Args...)
+	_, err := d.Cmd(service1Args...)
 	c.Assert(err, checker.IsNil)
 
-	out, err = d.Cmd(service2Args...)
+	_, err = d.Cmd(service2Args...)
 	c.Assert(err, checker.IsNil)
 
-	out, err = d.Cmd("service", "scale", "TestService1=2")
+	_, err = d.Cmd("service", "scale", "TestService1=2")
 	c.Assert(err, checker.IsNil)
 
-	out, err = d.Cmd("service", "scale", "TestService1=foobar")
+	out, err := d.Cmd("service", "scale", "TestService1=foobar")
 	c.Assert(err, checker.NotNil)
 
 	str := fmt.Sprintf("%s: invalid replicas value %s", service1Name, "foobar")

integration-cli/docker_cli_swarm_test.go

@@ -279,13 +279,13 @@ func (s *DockerSwarmSuite) TestSwarmPublishAdd(c *check.C) {
 	c.Assert(err, checker.IsNil)
 	c.Assert(strings.TrimSpace(out), checker.Not(checker.Equals), "")
 
-	out, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", name)
+	_, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", name)
 	c.Assert(err, checker.IsNil)
 
-	out, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", name)
+	_, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", name)
 	c.Assert(err, checker.IsNil)
 
-	out, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", "--publish-add", "80:20", name)
+	_, err = d.Cmd("service", "update", "--detach", "--publish-add", "80:80", "--publish-add", "80:20", name)
 	c.Assert(err, checker.NotNil)
 
 	out, err = d.Cmd("service", "inspect", "--format", "{{ .Spec.EndpointSpec.Ports }}", name)
@@ -841,14 +841,14 @@ func (s *DockerSwarmSuite) TestSwarmServiceTTY(c *check.C) {
 
 	// Without --tty
 	expectedOutput := "none"
-	out, err := d.Cmd("service", "create", "--detach", "--no-resolve-image", "--name", name, "busybox", "sh", "-c", ttyCheck)
+	_, err := d.Cmd("service", "create", "--detach", "--no-resolve-image", "--name", name, "busybox", "sh", "-c", ttyCheck)
 	c.Assert(err, checker.IsNil)
 
 	// Make sure task has been deployed.
 	waitAndAssert(c, defaultReconciliationTimeout, d.CheckActiveContainerCount, checker.Equals, 1)
 
 	// We need to get the container id.
-	out, err = d.Cmd("ps", "-q", "--no-trunc")
+	out, err := d.Cmd("ps", "-q", "--no-trunc")
 	c.Assert(err, checker.IsNil)
 	id := strings.TrimSpace(out)
 
@@ -857,14 +857,14 @@ func (s *DockerSwarmSuite) TestSwarmServiceTTY(c *check.C) {
 	c.Assert(out, checker.Contains, expectedOutput, check.Commentf("Expected '%s', but got %q", expectedOutput, out))
 
 	// Remove service
-	out, err = d.Cmd("service", "rm", name)
+	_, err = d.Cmd("service", "rm", name)
 	c.Assert(err, checker.IsNil)
 	// Make sure container has been destroyed.
 	waitAndAssert(c, defaultReconciliationTimeout, d.CheckActiveContainerCount, checker.Equals, 0)
 
 	// With --tty
 	expectedOutput = "TTY"
-	out, err = d.Cmd("service", "create", "--detach", "--no-resolve-image", "--name", name, "--tty", "busybox", "sh", "-c", ttyCheck)
+	_, err = d.Cmd("service", "create", "--detach", "--no-resolve-image", "--name", name, "--tty", "busybox", "sh", "-c", ttyCheck)
 	c.Assert(err, checker.IsNil)
 
 	// Make sure task has been deployed.
@@ -1069,6 +1069,7 @@ func (s *DockerSwarmSuite) TestSwarmInitLocked(c *check.C) {
 	c.Assert(unlockKey, checker.Not(checker.Equals), "")
 
 	outs, err = d.Cmd("swarm", "unlock-key", "-q")
+	c.Assert(err, checker.IsNil)
 	c.Assert(outs, checker.Equals, unlockKey+"\n")
 
 	c.Assert(getNodeStatus(c, d), checker.Equals, swarm.LocalNodeStateActive)
@@ -1168,6 +1169,7 @@ func (s *DockerSwarmSuite) TestSwarmLockUnlockCluster(c *check.C) {
 	c.Assert(unlockKey, checker.Not(checker.Equals), "")
 
 	outs, err = d1.Cmd("swarm", "unlock-key", "-q")
+	c.Assert(err, checker.IsNil)
 	c.Assert(outs, checker.Equals, unlockKey+"\n")
 
 	// The ones that got the cluster update should be set to locked
@@ -1234,6 +1236,7 @@ func (s *DockerSwarmSuite) TestSwarmJoinPromoteLocked(c *check.C) {
 	c.Assert(unlockKey, checker.Not(checker.Equals), "")
 
 	outs, err = d1.Cmd("swarm", "unlock-key", "-q")
+	c.Assert(err, checker.IsNil)
 	c.Assert(outs, checker.Equals, unlockKey+"\n")
 
 	// joined workers start off unlocked
@@ -1306,6 +1309,7 @@ func (s *DockerSwarmSuite) TestSwarmRotateUnlockKey(c *check.C) {
 	c.Assert(unlockKey, checker.Not(checker.Equals), "")
 
 	outs, err = d.Cmd("swarm", "unlock-key", "-q")
+	c.Assert(err, checker.IsNil)
 	c.Assert(outs, checker.Equals, unlockKey+"\n")
 
 	// Rotate multiple times
@@ -1390,6 +1394,7 @@ func (s *DockerSwarmSuite) TestSwarmClusterRotateUnlockKey(c *check.C) {
 	c.Assert(unlockKey, checker.Not(checker.Equals), "")
 
 	outs, err = d1.Cmd("swarm", "unlock-key", "-q")
+	c.Assert(err, checker.IsNil)
 	c.Assert(outs, checker.Equals, unlockKey+"\n")
 
 	// Rotate multiple times

integration-cli/docker_cli_swarm_unix_test.go

@@ -26,6 +26,7 @@ func (s *DockerSwarmSuite) TestSwarmVolumePlugin(c *check.C) {
 
 	// create a dummy volume to trigger lazy loading of the plugin
 	out, err = d.Cmd("volume", "create", "-d", "customvolumedriver", "hello")
+	c.Assert(err, checker.IsNil, check.Commentf(out))
 
 	// TODO(aaronl): It will take about 15 seconds for swarm to realize the
 	// plugin was loaded. Switching the test over to plugin v2 would avoid

integration-cli/docker_cli_update_unix_test.go

@@ -324,7 +324,7 @@ func (s *DockerSuite) TestUpdateWithNanoCPUs(c *check.C) {
 	c.Assert(err, checker.NotNil)
 	c.Assert(out, checker.Contains, "Conflicting options: CPU Quota cannot be updated as NanoCPUs has already been set")
 
-	out, _ = dockerCmd(c, "update", "--cpus", "0.8", "top")
+	dockerCmd(c, "update", "--cpus", "0.8", "top")
 	inspect, err = clt.ContainerInspect(context.Background(), "top")
 	c.Assert(err, checker.IsNil)
 	c.Assert(inspect.HostConfig.NanoCPUs, checker.Equals, int64(800000000))

integration-cli/docker_cli_userns_test.go

@@ -61,12 +61,12 @@ func (s *DockerDaemonSuite) TestDaemonUserNamespaceRootSetting(c *check.C) {
 	c.Assert(err, checker.IsNil, check.Commentf("Could not inspect running container: out: %q", pid))
 	// check the uid and gid maps for the PID to ensure root is remapped
 	// (cmd = cat /proc/<pid>/uid_map | grep -E '0\s+9999\s+1')
-	out, err = RunCommandPipelineWithOutput(
+	_, err = RunCommandPipelineWithOutput(
 		exec.Command("cat", "/proc/"+strings.TrimSpace(pid)+"/uid_map"),
 		exec.Command("grep", "-E", fmt.Sprintf("0[[:space:]]+%d[[:space:]]+", uid)))
 	c.Assert(err, check.IsNil)
 
-	out, err = RunCommandPipelineWithOutput(
+	_, err = RunCommandPipelineWithOutput(
 		exec.Command("cat", "/proc/"+strings.TrimSpace(pid)+"/gid_map"),
 		exec.Command("grep", "-E", fmt.Sprintf("0[[:space:]]+%d[[:space:]]+", gid)))
 	c.Assert(err, check.IsNil)

integration-cli/docker_cli_volume_test.go

@@ -300,10 +300,10 @@ func (s *DockerSuite) TestVolumeCLICreateLabel(c *check.C) {
 	testLabel := "foo"
 	testValue := "bar"
 
-	out, _, err := dockerCmdWithError("volume", "create", "--label", testLabel+"="+testValue, testVol)
+	_, _, err := dockerCmdWithError("volume", "create", "--label", testLabel+"="+testValue, testVol)
 	c.Assert(err, check.IsNil)
 
-	out, _ = dockerCmd(c, "volume", "inspect", "--format={{ .Labels."+testLabel+" }}", testVol)
+	out, _ := dockerCmd(c, "volume", "inspect", "--format={{ .Labels."+testLabel+" }}", testVol)
 	c.Assert(strings.TrimSpace(out), check.Equals, testValue)
 }
 
@@ -325,25 +325,25 @@ func (s *DockerSuite) TestVolumeCLICreateLabelMultiple(c *check.C) {
 		args = append(args, "--label", k+"="+v)
 	}
 
-	out, _, err := dockerCmdWithError(args...)
+	_, _, err := dockerCmdWithError(args...)
 	c.Assert(err, check.IsNil)
 
 	for k, v := range testLabels {
-		out, _ = dockerCmd(c, "volume", "inspect", "--format={{ .Labels."+k+" }}", testVol)
+		out, _ := dockerCmd(c, "volume", "inspect", "--format={{ .Labels."+k+" }}", testVol)
 		c.Assert(strings.TrimSpace(out), check.Equals, v)
 	}
 }
 
 func (s *DockerSuite) TestVolumeCLILsFilterLabels(c *check.C) {
 	testVol1 := "testvolcreatelabel-1"
-	out, _, err := dockerCmdWithError("volume", "create", "--label", "foo=bar1", testVol1)
+	_, _, err := dockerCmdWithError("volume", "create", "--label", "foo=bar1", testVol1)
 	c.Assert(err, check.IsNil)
 
 	testVol2 := "testvolcreatelabel-2"
-	out, _, err = dockerCmdWithError("volume", "create", "--label", "foo=bar2", testVol2)
+	_, _, err = dockerCmdWithError("volume", "create", "--label", "foo=bar2", testVol2)
 	c.Assert(err, check.IsNil)
 
-	out, _ = dockerCmd(c, "volume", "ls", "--filter", "label=foo")
+	out, _ := dockerCmd(c, "volume", "ls", "--filter", "label=foo")
 
 	// filter with label=key
 	c.Assert(out, checker.Contains, "testvolcreatelabel-1\n", check.Commentf("expected volume 'testvolcreatelabel-1' in output"))
@@ -367,15 +367,15 @@ func (s *DockerSuite) TestVolumeCLILsFilterLabels(c *check.C) {
 func (s *DockerSuite) TestVolumeCLILsFilterDrivers(c *check.C) {
 	// using default volume driver local to create volumes
 	testVol1 := "testvol-1"
-	out, _, err := dockerCmdWithError("volume", "create", testVol1)
+	_, _, err := dockerCmdWithError("volume", "create", testVol1)
 	c.Assert(err, check.IsNil)
 
 	testVol2 := "testvol-2"
-	out, _, err = dockerCmdWithError("volume", "create", testVol2)
+	_, _, err = dockerCmdWithError("volume", "create", testVol2)
 	c.Assert(err, check.IsNil)
 
 	// filter with driver=local
-	out, _ = dockerCmd(c, "volume", "ls", "--filter", "driver=local")
+	out, _ := dockerCmd(c, "volume", "ls", "--filter", "driver=local")
 	c.Assert(out, checker.Contains, "testvol-1\n", check.Commentf("expected volume 'testvol-1' in output"))
 	c.Assert(out, checker.Contains, "testvol-2\n", check.Commentf("expected volume 'testvol-2' in output"))
 
@@ -434,7 +434,7 @@ func (s *DockerSuite) TestVolumeCLIRmForceInUse(c *check.C) {
 	c.Assert(id, checker.Equals, name)
 
 	prefix, slash := getPrefixAndSlashFromDaemonPlatform()
-	out, e := dockerCmd(c, "create", "-v", "testvolume:"+prefix+slash+"foo", "busybox")
+	out, _ = dockerCmd(c, "create", "-v", "testvolume:"+prefix+slash+"foo", "busybox")
 	cid := strings.TrimSpace(out)
 
 	_, _, err := dockerCmdWithError("volume", "rm", "-f", name)
@@ -454,7 +454,7 @@ func (s *DockerSuite) TestVolumeCLIRmForceInUse(c *check.C) {
 	c.Assert(out, checker.Contains, name)
 
 	// Verify removing the volume after the container is removed works
-	_, e = dockerCmd(c, "rm", cid)
+	_, e := dockerCmd(c, "rm", cid)
 	c.Assert(e, check.Equals, 0)
 
 	_, e = dockerCmd(c, "volume", "rm", "-f", name)