Set up the folder with test and main file:

1// slices_test.go
2package slices
3
4import (
5    "testing"
6)
7
8// slices.go
9package slices
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1// slices_test.go
2func TestPushToIntSlice(t *testing.T) {
3    s := []int{1, 2, 3}
4    i := 4
5
6    exp := []int{1, 2, 3, 4}
7    res := Push(s, i)
8    for idx, val := range res {
9        if exp[idx] != val {
10            t.Fatalf("Expected %+v, got %+v", exp, res)
11        }
12    }
13}
14
15// Push append int to end of int slice
16func Push(a []int, b int) []int {
17    return append(a, b)
18}
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// slices_test.go
func TestPopIntFromSliceSlice(t *testing.T) {
    s := []int{1, 2, 3, 4}

    expArr := []int{1, 2, 3}
    exp := 4

    res, resArr := Pop(s)
    for idx, val := range resArr {
        if expArr[idx] != val {
            t.Fatalf("Expected %+v, got %+v", exp, res)
        }
    }

    if exp != res {
        t.Fatalf("Popped integer not as expected")
    }
}

// Pop return an integer from an array + array without last index
func Pop(a []int) (int, []int) {
    x, b := a[len(a)-1], a[:len(a)-1]
    return x, b
}
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// slices_test.go

// Unshift append as first element and return new slice
func Unshift(a []int, b int) []int {
    return append([]int{b}, a...)
}
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// slices_test.go

// Shift remove from front and return int and new slice
func Shift(a []int) (int, []int) {
    x, b := a[0], a[1:]
    return x, b
}
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