deprecate some fn commands

cmd/config/internal/commands/cmdwrap.go

@@ -5,6 +5,7 @@ package commands
 
 import (
 	"bytes"
+	"fmt"
 	"io"
 	"os"
 	"path/filepath"
@@ -47,6 +48,7 @@ Environment Variables:
 
 `,
 		RunE:               r.runE,
+		PreRunE:            r.preRunE,
 		SilenceUsage:       true,
 		FParseErrWhitelist: cobra.FParseErrWhitelist{UnknownFlags: true},
 		Args:               cobra.MinimumNArgs(1),
@@ -78,6 +80,12 @@ func WrapCommand() *cobra.Command {
 	return GetWrapRunner().Command
 }
 
+func (r *WrapRunner) preRunE(_ *cobra.Command, _ []string) error {
+	_, err := fmt.Fprintln(os.Stderr, `Command "wrap" is deprecated, this will no longer be available in kustomize v5.
+See discussion in https://github.com/kubernetes-sigs/kustomize/issues/3953.`)
+	return err
+}
+
 func (r *WrapRunner) runE(c *cobra.Command, args []string) error {
 	if r.getEnv == nil {
 		r.getEnv = os.Getenv

cmd/config/internal/commands/cmdxargs.go

@@ -60,6 +60,7 @@ $ kyaml cat pkg/ --function-config config.yaml --wrap-kind ResourceList | kyaml
 
 `,
 		RunE:               r.runE,
+		PreRunE:            r.preRunE,
 		SilenceUsage:       true,
 		FParseErrWhitelist: cobra.FParseErrWhitelist{UnknownFlags: true},
 		Args:               cobra.MinimumNArgs(1),
@@ -84,6 +85,12 @@ func XArgsCommand() *cobra.Command {
 	return GetXArgsRunner().Command
 }
 
+func (r *XArgsRunner) preRunE(_ *cobra.Command, _ []string) error {
+	_, err := fmt.Fprintln(os.Stderr, `Command "xargs" is deprecated, this will no longer be available in kustomize v5.
+See discussion in https://github.com/kubernetes-sigs/kustomize/issues/3953.`)
+	return err
+}
+
 func (r *XArgsRunner) runE(c *cobra.Command, _ []string) error {
 	if len(r.Args) == 0 {
 		r.Args = os.Args

cmd/config/internal/commands/sink.go

@@ -21,6 +21,8 @@ func GetSinkRunner(name string) *SinkRunner {
 		Example: commands.SinkExamples,
 		RunE:    r.runE,
 		Args:    cobra.MaximumNArgs(1),
+		Deprecated: "this will no longer be available in kustomize v5.\n" +
+			"See discussion in https://github.com/kubernetes-sigs/kustomize/issues/3953.",
 	}
 	runner.FixDocs(name, c)
 	r.Command = c

cmd/config/internal/commands/sink_test.go

@@ -290,7 +290,7 @@ metadata:
 spec:
   replicas: 3
 `
-	if !assert.Equal(t, expected, out.String()) {
+	if !assert.Contains(t, out.String(), expected) {
 		t.FailNow()
 	}
 }
@@ -335,7 +335,7 @@ items:
   }
 }
 `
-	if !assert.Equal(t, expected, out.String()) {
+	if !assert.Contains(t, out.String(), expected) {
 		println(out.String())
 		t.FailNow()
 	}

cmd/config/internal/commands/source.go

@@ -22,6 +22,8 @@ func GetSourceRunner(name string) *SourceRunner {
 		Long:    commands.SourceLong,
 		Example: commands.SourceExamples,
 		RunE:    r.runE,
+		Deprecated: "this will no longer be available in kustomize v5.\n" +
+			"See discussion in https://github.com/kubernetes-sigs/kustomize/issues/3953.",
 	}
 	runner.FixDocs(name, c)
 	c.Flags().StringVar(&r.WrapKind, "wrap-kind", kio.ResourceListKind,

cmd/config/internal/commands/source_test.go

@@ -81,7 +81,7 @@ spec:
 		return
 	}
 
-	if !assert.Equal(t, `apiVersion: config.kubernetes.io/v1alpha1
+	if !assert.Contains(t, b.String(), `apiVersion: config.kubernetes.io/v1alpha1
 kind: ResourceList
 items:
 - kind: Deployment
@@ -130,7 +130,7 @@ items:
       config.kubernetes.io/path: 'f2.yaml'
   spec:
     replicas: 3
-`, b.String()) {
+`) {
 		return
 	}
 }
@@ -191,12 +191,12 @@ func TestSourceCommandJSON(t *testing.T) {
 		return
 	}
 
-	if !assert.Equal(t, `apiVersion: config.kubernetes.io/v1alpha1
+	if !assert.Contains(t, b.String(), `apiVersion: config.kubernetes.io/v1alpha1
 kind: ResourceList
 items:
 - {"kind": "Deployment", "metadata": {"labels": {"app": "nginx2"}, "name": "foo", "annotations": {"app": "nginx2", config.kubernetes.io/index: '0', config.kubernetes.io/path: 'f1.json'}}, "spec": {"replicas": 1}}
 - {"apiVersion": "v1", "kind": "Abstraction", "metadata": {"name": "foo", "annotations": {"config.kubernetes.io/function": "container:\n  image: gcr.io/example/reconciler:v1\n", "config.kubernetes.io/local-config": "true", config.kubernetes.io/index: '0', config.kubernetes.io/path: 'f2.json'}}, "spec": {"replicas": 3}}
-`, b.String()) {
+`) {
 		return
 	}
 }
@@ -238,7 +238,7 @@ spec:
 		return
 	}
 
-	if !assert.Equal(t, `apiVersion: config.kubernetes.io/v1alpha1
+	if !assert.Contains(t, out.String(), `apiVersion: config.kubernetes.io/v1alpha1
 kind: ResourceList
 items:
 - kind: Deployment
@@ -260,7 +260,7 @@ items:
   spec:
     selector:
       app: nginx
-`, out.String()) {
+`) {
 		return
 	}
 }
@@ -299,11 +299,11 @@ func TestSourceCommandJSON_Stdin(t *testing.T) {
 		return
 	}
 
-	if !assert.Equal(t, `apiVersion: config.kubernetes.io/v1alpha1
+	if !assert.Contains(t, out.String(), `apiVersion: config.kubernetes.io/v1alpha1
 kind: ResourceList
 items:
 - {"kind": "Deployment", "metadata": {"labels": {"app": "nginx2"}, "name": "foo", "annotations": {"app": "nginx2", config.kubernetes.io/index: '0'}}, "spec": {"replicas": 1}}
-`, out.String()) {
+`) {
 		return
 	}
 }