Handle errors

api/filesys/fsnode.go

@@ -560,7 +560,7 @@ func isLegalFileNameForCreation(n string) bool {
 func (n *fsNode) RegExpGlob(pattern string) ([]string, error) {
 	var result []string
 	var expression = regexp.MustCompile(pattern)
-	n.WalkMe(func(path string, info os.FileInfo, err error) error {
+	err := n.WalkMe(func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
@@ -571,6 +571,9 @@ func (n *fsNode) RegExpGlob(pattern string) ([]string, error) {
 		}
 		return nil
 	})
+	if err != nil {
+		return nil, err
+	}
 	sort.Strings(result)
 	return result, nil
 }
@@ -582,7 +585,7 @@ func (n *fsNode) RegExpGlob(pattern string) ([]string, error) {
 // This is how /bin/ls behaves.
 func (n *fsNode) Glob(pattern string) ([]string, error) {
 	var result []string
-	n.WalkMe(func(path string, info os.FileInfo, err error) error {
+	err := n.WalkMe(func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
@@ -597,6 +600,9 @@ func (n *fsNode) Glob(pattern string) ([]string, error) {
 		}
 		return nil
 	})
+	if err != nil {
+		return nil, err
+	}
 	sort.Strings(result)
 	return result, nil
 }

api/internal/accumulator/loadconfigfromcrds.go

@@ -178,9 +178,12 @@ func loadCrdIntoConfig(
 			}
 		}
 		if property.Ref.GetURL() != nil {
-			loadCrdIntoConfig(
+			err = loadCrdIntoConfig(
 				theConfig, theGvk, theMap,
 				property.Ref.String(), append(path, propName))
+			if err != nil {
+				return
+			}
 		}
 	}
 	return nil

api/internal/accumulator/loadconfigfromcrds_test.go

@@ -7,6 +7,7 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	. "sigs.k8s.io/kustomize/api/internal/accumulator"
 	"sigs.k8s.io/kustomize/api/internal/plugins/builtinconfig"
@@ -162,16 +163,13 @@ func TestLoadCRDs(t *testing.T) {
 	}
 
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile("/testpath/crd.json", []byte(crdContent))
+	err := fSys.WriteFile("/testpath/crd.json", []byte(crdContent))
+	require.NoError(t, err)
 	ldr, err := loader.NewLoader(loader.RestrictionRootOnly, "/testpath", fSys)
-	if err != nil {
+	require.NoError(t, err)
-		t.Fatalf("unexpected error:%v", err)
-	}
 
 	actualTc, err := LoadConfigFromCRDs(ldr, []string{"crd.json"})
-	if err != nil {
+	require.NoError(t, err)
-		t.Fatalf("unexpected error:%v", err)
-	}
 	if !reflect.DeepEqual(actualTc, expectedTc) {
 		t.Fatalf("expected\n %v\n but got\n %v\n", expectedTc, actualTc)
 	}

api/internal/accumulator/resaccumulator_test.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	. "sigs.k8s.io/kustomize/api/internal/accumulator"
 	"sigs.k8s.io/kustomize/api/internal/plugins/builtinconfig"
 	"sigs.k8s.io/kustomize/api/provider"
@@ -224,20 +225,26 @@ func TestResolveVarConflicts(t *testing.T) {
 	// create accumulators holding apparently conflicting vars that are not
 	// actually in conflict because they point to the same concrete value.
 	rm0 := resmap.New()
-	rm0.Append(rf.FromMap(fooAws))
+	err := rm0.Append(rf.FromMap(fooAws))
+	require.NoError(t, err)
 	ac0 := MakeEmptyAccumulator()
-	ac0.AppendAll(rm0)
+	err = ac0.AppendAll(rm0)
-	ac0.MergeVars([]types.Var{varFoo})
+	require.NoError(t, err)
+	err = ac0.MergeVars([]types.Var{varFoo})
+	require.NoError(t, err)
 
 	rm1 := resmap.New()
-	rm1.Append(rf.FromMap(barAws))
+	err = rm1.Append(rf.FromMap(barAws))
+	require.NoError(t, err)
 	ac1 := MakeEmptyAccumulator()
-	ac1.AppendAll(rm1)
+	err = ac1.AppendAll(rm1)
-	ac1.MergeVars([]types.Var{varBar})
+	require.NoError(t, err)
+	err = ac1.MergeVars([]types.Var{varBar})
+	require.NoError(t, err)
 
 	// validate that two vars of the same name which reference the same concrete
 	// value do not produce a conflict.
-	err := ac0.MergeAccumulator(ac1)
+	err = ac0.MergeAccumulator(ac1)
 	if err == nil {
 		t.Fatalf("see bug gh-1600")
 	}
@@ -246,10 +253,13 @@ func TestResolveVarConflicts(t *testing.T) {
 	// two above (because it contains a variable whose name is used in the other
 	// accumulators AND whose concrete values are different).
 	rm2 := resmap.New()
-	rm2.Append(rf.FromMap(barGcp))
+	err = rm2.Append(rf.FromMap(barGcp))
+	require.NoError(t, err)
 	ac2 := MakeEmptyAccumulator()
-	ac2.AppendAll(rm2)
+	err = ac2.AppendAll(rm2)
-	ac2.MergeVars([]types.Var{varBar})
+	require.NoError(t, err)
+	err = ac2.MergeVars([]types.Var{varBar})
+	require.NoError(t, err)
 	err = ac1.MergeAccumulator(ac2)
 	if err == nil {
 		t.Fatalf("dupe vars w/ different concrete values should conflict")

api/internal/generators/configmap.go

@@ -40,7 +40,13 @@ func MakeConfigMap(
 	if err = rn.LoadMapIntoConfigMapData(m); err != nil {
 		return nil, err
 	}
-	copyLabelsAndAnnotations(rn, args.Options)
+	err = copyLabelsAndAnnotations(rn, args.Options)
-	setImmutable(rn, args.Options)
+	if err != nil {
+		return nil, err
+	}
+	err = setImmutable(rn, args.Options)
+	if err != nil {
+		return nil, err
+	}
 	return rn, nil
 }

api/internal/plugins/execplugin/execplugin.go

@@ -89,7 +89,10 @@ type argsConfig struct {
 
 func (p *ExecPlugin) processOptionalArgsFields() error {
 	var c argsConfig
-	yaml.Unmarshal(p.cfg, &c)
+	err := yaml.Unmarshal(p.cfg, &c)
+	if err != nil {
+		return err
+	}
 	if c.ArgsOneLiner != "" {
 		p.args, _ = shlex.Split(c.ArgsOneLiner)
 	}

api/internal/plugins/execplugin/execplugin_test.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	. "sigs.k8s.io/kustomize/api/internal/plugins/execplugin"
 	pLdr "sigs.k8s.io/kustomize/api/internal/plugins/loader"
@@ -21,11 +22,12 @@ import (
 
 func TestExecPluginConfig(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile("sed-input.txt", []byte(`
+	err := fSys.WriteFile("sed-input.txt", []byte(`
 s/$FOO/foo/g
 s/$BAR/bar baz/g
  \ \ \ 
 `))
+	require.NoError(t, err)
 	ldr, err := fLdr.NewLoader(
 		fLdr.RestrictionRootOnly, filesys.Separator, fSys)
 	if err != nil {
@@ -62,9 +64,10 @@ s/$BAR/bar baz/g
 	if err != nil {
 		t.Fatalf("unexpected err: %v", err)
 	}
-	p.Config(
+	err = p.Config(
 		resmap.NewPluginHelpers(ldr, pvd.GetFieldValidator(), rf, pc),
 		yaml)
+	require.NoError(t, err)
 
 	expected := "someteam.example.com/v1/sedtransformer/SedTransformer"
 	if !strings.HasSuffix(p.Path(), expected) {

api/internal/plugins/utils/utils.go

@@ -192,7 +192,9 @@ func UpdateResMapValues(pluginName string, h *resmap.PluginHelpers, output []byt
 	for _, id := range rm.AllIds() {
 		newIdx, _ := newMap.GetIndexOfCurrentId(id)
 		if newIdx == -1 {
-			rm.Remove(id)
+			if err = rm.Remove(id); err != nil {
+				return err
+			}
 		}
 	}
 

api/internal/plugins/utils/utils_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/api/konfig"
 	"sigs.k8s.io/kustomize/api/provider"
@@ -86,8 +87,10 @@ func TestUpdateResourceOptions(t *testing.T) {
 	}
 	for i, c := range cases {
 		name := fmt.Sprintf("test%d", i)
-		in.Append(makeConfigMap(rf, name, c.behavior, c.hashValue))
+		err := in.Append(makeConfigMap(rf, name, c.behavior, c.hashValue))
-		expected.Append(makeConfigMapOptions(rf, name, c.behavior, !c.needsHash))
+		require.NoError(t, err)
+		err = expected.Append(makeConfigMapOptions(rf, name, c.behavior, !c.needsHash))
+		require.NoError(t, err)
 	}
 	actual, err := UpdateResourceOptions(in)
 	assert.NoError(t, err)
@@ -105,10 +108,9 @@ func TestUpdateResourceOptionsWithInvalidHashAnnotationValues(t *testing.T) {
 	for i, c := range cases {
 		name := fmt.Sprintf("test%d", i)
 		in := resmap.New()
-		in.Append(makeConfigMap(rf, name, "", &c))
+		err := in.Append(makeConfigMap(rf, name, "", &c))
-		_, err := UpdateResourceOptions(in)
+		require.NoError(t, err)
-		if err == nil {
+		_, err = UpdateResourceOptions(in)
-			t.Errorf("expected error from value %q", c)
+		require.Error(t, err)
-		}
 	}
 }

api/konfig/plugins_test.go

@@ -9,7 +9,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
-
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/api/types"
 )
@@ -18,11 +18,11 @@ func TestDefaultAbsPluginHome_NoKustomizePluginHomeEnv(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
 	keep, isSet := os.LookupEnv(KustomizePluginHomeEnv)
 	if isSet {
-		_ = os.Unsetenv(KustomizePluginHomeEnv)
+		unsetenv(t, KustomizePluginHomeEnv)
 	}
 	_, err := DefaultAbsPluginHome(fSys)
 	if isSet {
-		os.Setenv(KustomizePluginHomeEnv, keep)
+		setenv(t, KustomizePluginHomeEnv, keep)
 	}
 	if err == nil {
 		t.Fatalf("expected err")
@@ -43,13 +43,13 @@ func TestDefaultAbsPluginHome_NoKustomizePluginHomeEnv(t *testing.T) {
 
 func TestDefaultAbsPluginHome_EmptyKustomizePluginHomeEnv(t *testing.T) {
 	keep, isSet := os.LookupEnv(KustomizePluginHomeEnv)
-	os.Setenv(KustomizePluginHomeEnv, "")
+	setenv(t, KustomizePluginHomeEnv, "")
 
 	_, err := DefaultAbsPluginHome(filesys.MakeFsInMemory())
 	if !isSet {
-		_ = os.Unsetenv(KustomizePluginHomeEnv)
+		unsetenv(t, KustomizePluginHomeEnv)
 	} else {
-		_ = os.Setenv(KustomizePluginHomeEnv, keep)
+		setenv(t, KustomizePluginHomeEnv, keep)
 	}
 	if err == nil {
 		t.Fatalf("expected err")
@@ -65,16 +65,15 @@ func TestDefaultAbsPluginHome_WithKustomizePluginHomeEnv(t *testing.T) {
 	keep, isSet := os.LookupEnv(KustomizePluginHomeEnv)
 	if !isSet {
 		keep = "whatever"
-		os.Setenv(KustomizePluginHomeEnv, keep)
+		setenv(t, KustomizePluginHomeEnv, keep)
 	}
-	fSys.Mkdir(keep)
+	err := fSys.Mkdir(keep)
+	require.NoError(t, err)
 	h, err := DefaultAbsPluginHome(fSys)
 	if !isSet {
-		_ = os.Unsetenv(KustomizePluginHomeEnv)
+		unsetenv(t, KustomizePluginHomeEnv)
-	}
-	if err != nil {
-		t.Fatalf("unexpected err: %v", err)
 	}
+	require.NoError(t, err)
 	if h != keep {
 		t.Fatalf("unexpected config dir: %s", h)
 	}
@@ -85,13 +84,14 @@ func TestDefaultAbsPluginHomeWithXdg(t *testing.T) {
 	keep, isSet := os.LookupEnv(XdgConfigHomeEnv)
 	if !isSet {
 		keep = "whatever"
-		os.Setenv(XdgConfigHomeEnv, keep)
+		setenv(t, XdgConfigHomeEnv, keep)
 	}
 	configDir := filepath.Join(keep, ProgramName, RelPluginHome)
-	fSys.Mkdir(configDir)
+	err := fSys.Mkdir(configDir)
+	require.NoError(t, err)
 	h, err := DefaultAbsPluginHome(fSys)
 	if !isSet {
-		_ = os.Unsetenv(XdgConfigHomeEnv)
+		unsetenv(t, XdgConfigHomeEnv)
 	}
 	if err != nil {
 		t.Fatalf("unexpected err: %v", err)
@@ -105,11 +105,11 @@ func TestDefaultAbsPluginHomeNoConfig(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
 	keep, isSet := os.LookupEnv(XdgConfigHomeEnv)
 	if isSet {
-		_ = os.Unsetenv(XdgConfigHomeEnv)
+		unsetenv(t, XdgConfigHomeEnv)
 	}
 	_, err := DefaultAbsPluginHome(fSys)
 	if isSet {
-		os.Setenv(XdgConfigHomeEnv, keep)
+		setenv(t, XdgConfigHomeEnv, keep)
 	}
 	if err == nil {
 		t.Fatalf("expected err")
@@ -121,13 +121,13 @@ func TestDefaultAbsPluginHomeNoConfig(t *testing.T) {
 
 func TestDefaultAbsPluginHomeEmptyXdgConfig(t *testing.T) {
 	keep, isSet := os.LookupEnv(XdgConfigHomeEnv)
-	os.Setenv(XdgConfigHomeEnv, "")
+	setenv(t, XdgConfigHomeEnv, "")
 	if isSet {
-		_ = os.Unsetenv(XdgConfigHomeEnv)
+		unsetenv(t, XdgConfigHomeEnv)
 	}
 	_, err := DefaultAbsPluginHome(filesys.MakeFsInMemory())
 	if isSet {
-		os.Setenv(XdgConfigHomeEnv, keep)
+		setenv(t, XdgConfigHomeEnv, keep)
 	}
 	if err == nil {
 		t.Fatalf("expected err")
@@ -142,14 +142,16 @@ func TestDefaultAbsPluginHomeNoXdgWithDotConfig(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
 	configDir := filepath.Join(
 		HomeDir(), XdgConfigHomeEnvDefault, ProgramName, RelPluginHome)
-	fSys.Mkdir(configDir)
+	err := fSys.Mkdir(configDir)
+	require.NoError(t, err)
 	keep, isSet := os.LookupEnv(XdgConfigHomeEnv)
 	if isSet {
-		_ = os.Unsetenv(XdgConfigHomeEnv)
+		unsetenv(t, XdgConfigHomeEnv)
 	}
-	s, _ := DefaultAbsPluginHome(fSys)
+	s, err := DefaultAbsPluginHome(fSys)
+	require.NoError(t, err)
 	if isSet {
-		os.Setenv(XdgConfigHomeEnv, keep)
+		setenv(t, XdgConfigHomeEnv, keep)
 	}
 	if s != configDir {
 		t.Fatalf("unexpected config dir: %s", s)
@@ -160,16 +162,26 @@ func TestDefaultAbsPluginHomeNoXdgJustHomeDir(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
 	configDir := filepath.Join(
 		HomeDir(), ProgramName, RelPluginHome)
-	fSys.Mkdir(configDir)
+	err := fSys.Mkdir(configDir)
+	require.NoError(t, err)
 	keep, isSet := os.LookupEnv(XdgConfigHomeEnv)
 	if isSet {
-		_ = os.Unsetenv(XdgConfigHomeEnv)
+		unsetenv(t, XdgConfigHomeEnv)
 	}
-	s, _ := DefaultAbsPluginHome(fSys)
+	s, err := DefaultAbsPluginHome(fSys)
+	require.NoError(t, err)
 	if isSet {
-		os.Setenv(XdgConfigHomeEnv, keep)
+		setenv(t, XdgConfigHomeEnv, keep)
 	}
 	if s != configDir {
 		t.Fatalf("unexpected config dir: %s", s)
 	}
 }
+
+func setenv(t *testing.T, key, value string) {
+	require.NoError(t, os.Setenv(key, value))
+}
+
+func unsetenv(t *testing.T, key string) {
+	require.NoError(t, os.Unsetenv(key))
+}

api/kv/kv_test.go

@@ -7,6 +7,7 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	ldr "sigs.k8s.io/kustomize/api/loader"
 	valtest_test "sigs.k8s.io/kustomize/api/testutils/valtest"
@@ -83,7 +84,8 @@ func TestKeyValuesFromFileSources(t *testing.T) {
 	}
 
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile("/files/app-init.ini", []byte("FOO=bar"))
+	err := fSys.WriteFile("/files/app-init.ini", []byte("FOO=bar"))
+	require.NoError(t, err)
 	kvl := makeKvLoader(fSys)
 	for _, tc := range tests {
 		kvs, err := kvl.keyValuesFromFileSources(tc.sources)

cmd/config/completion/completion.go

@@ -17,17 +17,18 @@ func NewCommand() *cobra.Command {
 		DisableFlagsInUseLine: true,
 		ValidArgs:             []string{"bash", "zsh", "fish", "powershell"},
 		Args:                  cobra.ExactValidArgs(1),
-		Run: func(cmd *cobra.Command, args []string) {
+		RunE: func(cmd *cobra.Command, args []string) error {
 			switch args[0] {
 			case "bash":
-				cmd.Root().GenBashCompletion(os.Stdout)
+				return cmd.Root().GenBashCompletion(os.Stdout)
 			case "zsh":
-				cmd.Root().GenZshCompletion(os.Stdout)
+				return cmd.Root().GenZshCompletion(os.Stdout)
 			case "fish":
-				cmd.Root().GenFishCompletion(os.Stdout, true)
+				return cmd.Root().GenFishCompletion(os.Stdout, true)
 			case "powershell":
-				cmd.Root().GenPowerShellCompletion(os.Stdout)
+				return cmd.Root().GenPowerShellCompletion(os.Stdout)
 			}
+			return nil
 		},
 	}
 }

cmd/config/internal/commands/annotate.go

@@ -104,9 +104,9 @@ func (r *AnnotateRunner) ExecuteCmd(w io.Writer, pkgPath string) error {
 			return err
 		}
 		// print error message and continue if there are multiple packages to annotate
-		fmt.Fprintf(w, "%s\n", err.Error())
+		_, _ = fmt.Fprintf(w, "%s\n", err.Error())
 	} else {
-		fmt.Fprint(w, "added annotations in the package\n")
+		_, _ = fmt.Fprint(w, "added annotations in the package\n")
 	}
 	return nil
 }

cmd/pluginator/internal/builtinplugin/builtinplugin.go

@@ -27,7 +27,7 @@ const (
 
 // ConvertToBuiltInPlugin converts the input plugin file to
 // kustomize builtin plugin and writes it to proper directory
-func ConvertToBuiltInPlugin() error {
+func ConvertToBuiltInPlugin() (retErr error) {
 	root, err := inputFileRoot()
 	if err != nil {
 		return err
@@ -47,7 +47,12 @@ func ConvertToBuiltInPlugin() error {
 	if err != nil {
 		return err
 	}
-	defer w.close()
+	defer func() {
+		closeErr := w.Close()
+		if retErr == nil {
+			retErr = closeErr
+		}
+	}()
 
 	// This particular phrasing is required.
 	w.write(
@@ -139,10 +144,10 @@ func makeOutputFileName(root string) string {
 		"..", "..", "..", "api", packageForGeneratedCode, root+".go")
 }
 
-func (w *writer) close() {
+func (w *writer) Close() error {
 	// Do this for debugging.
 	// fmt.Println("Generated " + makeOutputFileName(w.root))
-	w.f.Close()
+	return w.f.Close()
 }
 
 func (w *writer) write(line string) {

kustomize/commands/edit/add/addbase_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/kustomize/v4/commands/internal/kustfile"
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v4/commands/internal/testutils"
@@ -21,7 +22,8 @@ func TestAddBaseHappyPath(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
 	bases := strings.Split(baseDirectoryPaths, ",")
 	for _, base := range bases {
-		fSys.Mkdir(base)
+		err := fSys.Mkdir(base)
+		require.NoError(t, err)
 	}
 	testutils_test.WriteTestKustomization(fSys)
 
@@ -41,7 +43,8 @@ func TestAddBaseAlreadyThere(t *testing.T) {
 	// Create fake directories
 	bases := strings.Split(baseDirectoryPaths, ",")
 	for _, base := range bases {
-		fSys.Mkdir(base)
+		err := fSys.Mkdir(base)
+		require.NoError(t, err)
 	}
 	testutils_test.WriteTestKustomization(fSys)
 

kustomize/commands/edit/add/addcomponent_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v4/commands/internal/testutils"
 )
@@ -21,8 +22,10 @@ sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
 
 func TestAddComponentHappyPath(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(componentFileName, []byte(componentFileContent))
+	err := fSys.WriteFile(componentFileName, []byte(componentFileContent))
-	fSys.WriteFile(componentFileName+"another", []byte(componentFileContent))
+	require.NoError(t, err)
+	err = fSys.WriteFile(componentFileName+"another", []byte(componentFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddComponent(fSys)
@@ -36,7 +39,8 @@ func TestAddComponentHappyPath(t *testing.T) {
 
 func TestAddComponentAlreadyThere(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile(componentFileName, []byte(componentFileContent))
+	err := fSys.WriteFile(componentFileName, []byte(componentFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddComponent(fSys)
@@ -49,15 +53,16 @@ func TestAddComponentAlreadyThere(t *testing.T) {
 
 func TestAddKustomizationFileAsComponent(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile(componentFileName, []byte(componentFileContent))
+	err := fSys.WriteFile(componentFileName, []byte(componentFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddComponent(fSys)
 	args := []string{componentFileName}
-	assert.NoError(t, cmd.RunE(cmd, args))
+	require.NoError(t, cmd.RunE(cmd, args))
 
 	content, err := testutils_test.ReadTestKustomization(fSys)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 	assert.NotContains(t, string(content), componentFileName)
 }
 
@@ -66,6 +71,5 @@ func TestAddComponentNoArgs(t *testing.T) {
 
 	cmd := newCmdAddComponent(fSys)
 	err := cmd.Execute()
-	assert.Error(t, err)
+	assert.EqualError(t, err, "must specify a component file")
-	assert.Equal(t, "must specify a component file", err.Error())
 }

kustomize/commands/edit/add/addmetadata_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	valtest_test "sigs.k8s.io/kustomize/api/testutils/valtest"
 	"sigs.k8s.io/kustomize/api/types"
@@ -163,8 +164,9 @@ func TestAddAnnotationForce(t *testing.T) {
 	// but trying to add it with --force should
 	v = valtest_test.MakeHappyMapValidator(t)
 	cmd = newCmdAddAnnotation(fSys, v.Validator)
-	cmd.Flag("force").Value.Set("true")
+	err = cmd.Flag("force").Value.Set("true")
-	assert.NoError(t, cmd.RunE(cmd, args))
+	require.NoError(t, err)
+	require.NoError(t, cmd.RunE(cmd, args))
 	v.VerifyCall()
 }
 
@@ -266,7 +268,8 @@ func TestAddLabelForce(t *testing.T) {
 	// but trying to add it with --force should
 	v = valtest_test.MakeHappyMapValidator(t)
 	cmd = newCmdAddLabel(fSys, v.Validator)
-	cmd.Flag("force").Value.Set("true")
+	err = cmd.Flag("force").Value.Set("true")
+	require.NoError(t, err)
 	assert.NoError(t, cmd.RunE(cmd, args))
 	v.VerifyCall()
 }

kustomize/commands/edit/add/addpatch_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v4/commands/internal/testutils"
 )
@@ -28,7 +29,8 @@ Lorem ipsum dolor sit amet, consectetur adipiscing elit,
 
 func TestAddPatchWithFilePath(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	err := fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddPatch(fSys)
@@ -53,7 +55,8 @@ func TestAddPatchWithFilePath(t *testing.T) {
 
 func TestAddPatchWithPatchContent(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	err := fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddPatch(fSys)
@@ -78,7 +81,8 @@ func TestAddPatchWithPatchContent(t *testing.T) {
 
 func TestAddPatchAlreadyThere(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	err := fSys.WriteFile(patchFileName, []byte(patchFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddPatch(fSys)

kustomize/commands/edit/add/addresource_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v4/commands/internal/testutils"
 )
@@ -21,8 +22,10 @@ sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
 
 func TestAddResourceHappyPath(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
+	err := fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
-	fSys.WriteFile(resourceFileName+"another", []byte(resourceFileContent))
+	require.NoError(t, err)
+	err = fSys.WriteFile(resourceFileName+"another", []byte(resourceFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddResource(fSys)
@@ -36,7 +39,8 @@ func TestAddResourceHappyPath(t *testing.T) {
 
 func TestAddResourceAlreadyThere(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
+	err := fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddResource(fSys)
@@ -49,7 +53,8 @@ func TestAddResourceAlreadyThere(t *testing.T) {
 
 func TestAddKustomizationFileAsResource(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
+	err := fSys.WriteFile(resourceFileName, []byte(resourceFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddResource(fSys)

kustomize/commands/edit/add/addtransformer_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/kustomize/v4/commands/internal/kustfile"
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v4/commands/internal/testutils"
@@ -22,8 +23,10 @@ sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
 
 func TestAddTransformerHappyPath(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(transformerFileName, []byte(transformerFileContent))
+	err := fSys.WriteFile(transformerFileName, []byte(transformerFileContent))
-	fSys.WriteFile(transformerFileName+"another", []byte(transformerFileContent))
+	require.NoError(t, err)
+	err = fSys.WriteFile(transformerFileName+"another", []byte(transformerFileContent))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddTransformer(fSys)
@@ -37,7 +40,8 @@ func TestAddTransformerHappyPath(t *testing.T) {
 
 func TestAddTransformerAlreadyThere(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(transformerFileName, []byte(transformerFileName))
+	err := fSys.WriteFile(transformerFileName, []byte(transformerFileName))
+	require.NoError(t, err)
 	testutils_test.WriteTestKustomization(fSys)
 
 	cmd := newCmdAddTransformer(fSys)
@@ -61,18 +65,18 @@ func TestAddTransformerNoArgs(t *testing.T) {
 
 	cmd := newCmdAddTransformer(fSys)
 	err := cmd.Execute()
-	assert.Error(t, err)
+	assert.EqualError(t, err, "must specify a transformer file")
-	assert.Equal(t, "must specify a transformer file", err.Error())
 }
 
 func TestAddTransformerMissingKustomizationYAML(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.WriteFile(transformerFileName, []byte(transformerFileContent))
+	err := fSys.WriteFile(transformerFileName, []byte(transformerFileContent))
-	fSys.WriteFile(transformerFileName+"another", []byte(transformerFileContent))
+	require.NoError(t, err)
+	err = fSys.WriteFile(transformerFileName+"another", []byte(transformerFileContent))
+	require.NoError(t, err)
 
 	cmd := newCmdAddTransformer(fSys)
 	args := []string{transformerFileName + "*"}
-	err := cmd.RunE(cmd, args)
+	err = cmd.RunE(cmd, args)
-	assert.Error(t, err)
+	assert.EqualError(t, err, "Missing kustomization file 'kustomization.yaml'.\n")
-	assert.Equal(t, "Missing kustomization file 'kustomization.yaml'.\n", err.Error())
 }

kustomize/commands/edit/add/flagsandargs_test.go

@@ -8,7 +8,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
-
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 )
 
@@ -88,13 +88,17 @@ func TestDataConfigValidation_Flags(t *testing.T) {
 
 func TestExpandFileSource(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.Create("dir/fa1")
+	_, err := fSys.Create("dir/fa1")
-	fSys.Create("dir/fa2")
+	require.NoError(t, err)
-	fSys.Create("dir/readme")
+	_, err = fSys.Create("dir/fa2")
+	require.NoError(t, err)
+	_, err = fSys.Create("dir/readme")
+	require.NoError(t, err)
 	fa := flagsAndArgs{
 		FileSources: []string{"dir/fa*"},
 	}
-	fa.ExpandFileSource(fSys)
+	err = fa.ExpandFileSource(fSys)
+	require.NoError(t, err)
 	expected := []string{
 		"dir/fa1",
 		"dir/fa2",
@@ -106,14 +110,19 @@ func TestExpandFileSource(t *testing.T) {
 
 func TestExpandFileSourceWithKey(t *testing.T) {
 	fSys := filesys.MakeEmptyDirInMemory()
-	fSys.Create("dir/faaaaaaaaaabbbbbbbbbccccccccccccccccc")
+	_, err := fSys.Create("dir/faaaaaaaaaabbbbbbbbbccccccccccccccccc")
-	fSys.Create("dir/foobar")
+	require.NoError(t, err)
-	fSys.Create("dir/simplebar")
+	_, err = fSys.Create("dir/foobar")
-	fSys.Create("dir/readme")
+	require.NoError(t, err)
+	_, err = fSys.Create("dir/simplebar")
+	require.NoError(t, err)
+	_, err = fSys.Create("dir/readme")
+	require.NoError(t, err)
 	fa := flagsAndArgs{
 		FileSources: []string{"foo-key=dir/fa*", "bar-key=dir/foobar", "dir/simplebar"},
 	}
-	fa.ExpandFileSource(fSys)
+	err = fa.ExpandFileSource(fSys)
+	require.NoError(t, err)
 	expected := []string{
 		"foo-key=dir/faaaaaaaaaabbbbbbbbbccccccccccccccccc",
 		"bar-key=dir/foobar",
@@ -126,13 +135,16 @@ func TestExpandFileSourceWithKey(t *testing.T) {
 
 func TestExpandFileSourceWithKeyAndError(t *testing.T) {
 	fSys := filesys.MakeFsInMemory()
-	fSys.Create("dir/fa1")
+	_, err := fSys.Create("dir/fa1")
-	fSys.Create("dir/fa2")
+	require.NoError(t, err)
-	fSys.Create("dir/readme")
+	_, err = fSys.Create("dir/fa2")
+	require.NoError(t, err)
+	_, err = fSys.Create("dir/readme")
+	require.NoError(t, err)
 	fa := flagsAndArgs{
 		FileSources: []string{"foo-key=dir/fa*"},
 	}
-	err := fa.ExpandFileSource(fSys)
+	err = fa.ExpandFileSource(fSys)
 	if err == nil {
 		t.Fatalf("FileSources should not be correctly expanded: %v", fa.FileSources)
 	}

kustomize/commands/internal/kustfile/kustomizationfile_test.go

@@ -9,7 +9,7 @@ import (
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-
+	"github.com/stretchr/testify/require"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/api/konfig"
 	"sigs.k8s.io/kustomize/api/types"
@@ -125,7 +125,8 @@ configMapGenerator:
 `
 	for _, n := range konfig.RecognizedKustomizationFileNames() {
 		fSys := filesys.MakeFsInMemory()
-		fSys.WriteFile(n, []byte(kcontent))
+		err := fSys.WriteFile(n, []byte(kcontent))
+		require.NoError(t, err)
 		k, err := NewKustomizationFile(fSys)
 		if err != nil {
 			t.Fatalf("Unexpected Error: %v", err)

kyaml/yaml/rnode_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"gopkg.in/yaml.v3"
 )
 
@@ -1671,7 +1672,8 @@ func TestSetName(t *testing.T) {
 	if err := rn.UnmarshalJSON([]byte(deploymentBiggerJson)); err != nil {
 		t.Fatalf("unexpected unmarshaljson err: %v", err)
 	}
-	rn.SetName("marge")
+	err := rn.SetName("marge")
+	require.NoError(t, err)
 	if expected, actual := "marge", rn.GetName(); expected != actual {
 		t.Fatalf("expected '%s', got '%s'", expected, actual)
 	}
@@ -1682,12 +1684,15 @@ func TestSetNamespace(t *testing.T) {
 	if err := rn.UnmarshalJSON([]byte(deploymentBiggerJson)); err != nil {
 		t.Fatalf("unexpected unmarshaljson err: %v", err)
 	}
-	rn.SetNamespace("flanders")
+	err := rn.SetNamespace("flanders")
-	meta, _ := rn.GetMeta()
+	require.NoError(t, err)
+	meta, err := rn.GetMeta()
+	require.NoError(t, err)
 	if expected, actual := "flanders", meta.Namespace; expected != actual {
 		t.Fatalf("expected '%s', got '%s'", expected, actual)
 	}
 }
+
 func TestSetLabels(t *testing.T) {
 	rn := NewRNode(nil)
 	if err := rn.UnmarshalJSON([]byte(deploymentBiggerJson)); err != nil {

kyaml/yaml/types.go

@@ -213,7 +213,10 @@ func String(node *yaml.Node, opts ...string) (string, error) {
 	b := &bytes.Buffer{}
 	e := NewEncoder(b)
 	err := e.Encode(node)
-	e.Close()
+	errClose := e.Close()
+	if err == nil {
+		err = errClose
+	}
 	val := b.String()
 	if optsSet.Has(Trim) {
 		val = strings.TrimSpace(val)

plugin/someteam.example.com/v1/calvinduplicator/CalvinDuplicator.go

@@ -37,11 +37,20 @@ func (p *plugin) Transform(m resmap.ResMap) error {
 		if r.GetName() == p.Name {
 			for i := 1; i <= p.Count; i++ {
 				c := r.DeepCopy()
-				c.SetName(fmt.Sprintf("%s-%d", p.Name, i))
+				err := c.SetName(fmt.Sprintf("%s-%d", p.Name, i))
-				m.Append(c)
+				if err != nil {
+					return err
+				}
+				err = m.Append(c)
+				if err != nil {
+					return err
+				}
 			}
 		} else {
-			m.Append(r)
+			err := m.Append(r)
+			if err != nil {
+				return err
+			}
 		}
 	}
 	return nil