You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: util_test.go
    path of file: ./repos/istio/pilot/pkg/networking/core/v1alpha3/envoyfilter
    
    the code of the file until where you have to start completion: // Copyright Istio Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed 
    
func TestReplaceAndInsert(t *testing.T) {
	f := func(e int) (bool, int) {
		// replace 1 with 10
		if e == 1 {
			return true, 10
		}
		return false, 0
	}

	cases := []struct {
		name         string
		input        []int
		replace      []int
		insertBefore []int
		insertAfter  []int
		applied      bool
	}{
		{
			name:         "nil slice",
			input:        nil,
			replace:      nil,
			insertBefore: nil,
			insertAfter:  nil,
			applied:      false,
		},
		{
			name:         "the first",
			input:        []int{1, 2, 3},
			replace:      []int{10, 2, 3},
			insertBefore: []int{10, 1, 2, 3},
			insertAfter:  []int{1, 10, 2, 3},
			applied:      true,
		},
		{
			name:         "the middle",
			input:        []int{0, 1, 2, 3},
			replace:      []int{0, 10, 2, 3},
			insertBefore: []int{0, 10, 1, 2, 3},
			insertAfter:  []int{0, 1, 10, 2, 3},
			applied:      true,
		},
		{
			name:         "the last",
			input:        []int{3, 2, 1},
			replace:      []int{3, 2, 10},
			insertBefore: []int{3, 2, 10, 1},
			insertAfter:  []int{3, 2, 1, 10},
			applied:      true,
		},
		{
			name:         "match multiple",
			input:        []int{1, 2, 1},
			replace:      []int{10, 2, 1},
			insertBefore: []int{10, 1, 2, 1},
			insertAfter:  []int{1, 10, 2, 1},
			applied:      true,
		},
		{
			name:         "not exists",
			input:        []int{2, 3},
			replace:      []int{2, 3},
			insertBefore: []int{2, 3},
			insertAfter:  []int{2, 3},
			applied:      false,
		},
	}

	// all the test cases are to find the position of the number 1 in the slice,
	// and then replace (or insert before, or insert after) it with 10.
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			// replaceFunc
			got, applied := replaceFunc(slices.Clone(c.input), f)
			if !slices.Equal(c.replace, got) {
				t.Errorf("replaceFunc: want %+v but got %+v", c.replace, got)
			}
			if c.applied != applied {
				t.Errorf("replaceFunc: want %+v but got %+v", c.applied, applied)
			}

			// insertBeforeFunc
			got, applied = insertBeforeFunc(slices.Clone(c.input), f)
			if !slices.Equal(c.insertBefore, got) {
				t.Errorf("insertBeforeFunc: want %+v but got %+v", c.insertBefore, got)
			}
			if c.applied != applied {
				t.Errorf("insertBeforeFunc: want %+v but got %+v", c.applied, applied)
			}

			// insertAfterFunc
			got, applied = insertAfterFunc(slices.Clone(c.input), f)
			if !slices.Equal(c.insertAfter, got) {
				t.Errorf("insertAfterFunc: want %+v but got %+v", c.insertAfter, got)
			}
			if c.applied != applied {
				t.Errorf("insertAfterFunc: want %+v but got %+v", c.applied, applied)
			}
		})
	}
}