func IstioUserAgent() string {
	return adjustCommand(os.Args[0]) + "/" + istioversion.Info.Version
}

// SetRestDefaults is a helper function that sets default values for the given rest.Config.
// This function is idempotent.
func SetRestDefaults(config *rest.Config) *rest.Config {
	if config.GroupVersion == nil || config.GroupVersion.Empty() {
		config.GroupVersion = &corev1.SchemeGroupVersion
	}
	if len(config.APIPath) == 0 {

			if actual != tc.want {
				t.Fatalf("Unexpected result.\nExpected:\n%v\nActual:\n%v", tc.want, actual)
			}
			t.Run("idempotency", func(t *testing.T) {
				actual := appendMultusNetwork(actual, "istio-cni")
				if actual != tc.want {
					t.Fatalf("Function is not idempotent.\nExpected:\n%v\nActual:\n%v", tc.want, actual)
				}
			})
		})
	}
}

func Test_updateClusterEnvs(t *testing.T) {

There are also some constraints and possible limitations.

[[sec:constrained_syntax]]
==== Constrained Syntax

The `plugins {}` block does not support arbitrary code.

It is constrained to be idempotent (produce the same result every time) and side effect-free (safe for Gradle to execute at any time).

The form is:

====
[.multi-language-sample]
=====
.build.gradle.kts
[source,kotlin]
----

	// Unreserve is called by the scheduling framework when a reserved pod was
	// rejected, an error occurred during reservation of subsequent plugins, or
	// in a later phase. The Unreserve method implementation must be idempotent
	// and may be called by the scheduler even if the corresponding Reserve
	// method for the same plugin was not called.
	Unreserve(ctx context.Context, state *CycleState, p *v1.Pod, nodeName string)
}

	return s.muxAndDiscoveryCompleteSignals
}

// RegisterDestroyFunc registers a function that will be called during Destroy().
// The function have to be idempotent and prepared to be called more than once.
func (s *GenericAPIServer) RegisterDestroyFunc(destroyFn func()) {
	s.destroyFns = append(s.destroyFns, destroyFn)
}

// mounting, or unmounting a volume that are executed with a NewNestedPendingOperations which
// prevents more than one operation from being triggered on the same volume.
//
// These operations should be idempotent (for example, AttachVolume should
// still succeed if the volume is already attached to the node, etc.). However,
// they depend on the volume plugins to implement this behavior.
//

}

// Close - calls the cleanup actions in reverse order
func (g *GetObjectReader) Close() error {
	if g == nil {
		return nil
	}
	// sync.Once is used here to ensure that Close() is
	// idempotent.
	g.once.Do(func() {
		for i := len(g.cleanUpFns) - 1; i >= 0; i-- {
			g.cleanUpFns[i]()
		}
	})
	return nil
}

// compressionIndexEncrypter returns a function that will read data from input,

type ObjectReadSeekCloser struct {
	segmentReader ObjectSegmentReaderFn

	size   int64 // actual object size regardless of compression/encryption
	offset int64
	reader io.ReadCloser

	// reader can be closed idempotently multiple times
	closerOnce sync.Once
	// Error storing reader.Close()
	closerErr error
}

// NewObjectReadSeekCloser creates a new ObjectReadSeekCloser.

	pod := req.pod.DeepCopy()
	prevStatus := injectionStatus(pod)
	if prevStatus == nil {
		return req.pod
	}
	// We found a previous status annotation. Possibly we are re-injecting the pod
	// To ensure idempotency, remove our injected containers first
	for _, c := range prevStatus.Containers {
		pod.Spec.Containers = modifyContainers(pod.Spec.Containers, c, Remove)
	}
	for _, c := range prevStatus.InitContainers {

			existingKubeConfig: invalidConfig,
			kubeConfig:         invalidConfig,
			expectedError:      true,
		},
		{ // if KubeConfig is equal to the existingKubeConfig - refers to the same cluster -, use the existing (Test idempotency)
			name:               "KubeConfig refers to the same cluster",
			existingKubeConfig: config,
			kubeConfig:         config,
		},