added tests for new transformer utils package

worker/internal/benthos/transformers/utils/utils_test.go

@@ -0,0 +1,71 @@
+package transformer_utils
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+// returns a random index from a one-dimensional slice
+func TestGetRandomValueFromSliceEmptySlice(t *testing.T) {
+
+	arr := []string{}
+	_, err := GetRandomValueFromSlice(arr)
+	assert.Error(t, err, "Expected an error for the empty slice")
+
+}
+
+func TestGetRandomValueFromSliceNonEmptySlice(t *testing.T) {
+
+	arr := []string{"a", "b", "c"}
+	res, err := GetRandomValueFromSlice(arr)
+	assert.NoError(t, err)
+	assert.Contains(t, arr, res, "Expected the response to be included in the input array")
+
+}
+
+func TestGenerateRandomNumberWithBoundsMinError(t *testing.T) {
+
+	_, err := GenerateRandomNumberWithBounds(10, 1)
+	assert.Error(t, err, "Expected an error such that the min is greated than the max")
+}
+
+func TestGenerateRandomNumberWithBoundsMinEqualMax(t *testing.T) {
+
+	const minMax = 5
+	val, err := GenerateRandomNumberWithBounds(minMax, minMax)
+	assert.NoError(t, err, "Did not expect an error when min == max")
+	assert.Equal(t, minMax, val, "Expected value to be equal to min/max")
+
+}
+
+func TestGenerateRandomNumberWithBoundsValid(t *testing.T) {
+
+	min, max := 2, 9
+	val, err := GenerateRandomNumberWithBounds(min, max)
+	assert.NoError(t, err, "Did not expect an error for valid range")
+	assert.True(t, val >= min && val <= max, "Expected value to be within the range")
+}
+
+func TestSliceStringEmptyString(t *testing.T) {
+
+	res := SliceString("", 10)
+	assert.Empty(t, res, "Expected result to be an empty string")
+}
+
+func TestSliceStringShortString(t *testing.T) {
+
+	s := "short"
+	res := SliceString(s, 10)
+	assert.Equal(t, s, res, "Expected result to be equal to the input string")
+
+}
+
+func TestSliceStringValidSlice(t *testing.T) {
+
+	s := "hello, world"
+	length := 5
+	expected := "hello"
+	res := SliceString(s, length)
+	assert.Equal(t, expected, res, "Expected result to be a substring of the input string with the specified length")
+}