feat: Randomizer

rand/randomizer_test.go

@@ -0,0 +1,86 @@
+package rand
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestRandomizer_RangeUint32_MinEqualsMax(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.RangeUint32(5, 5)
+	assert.Equal(t, uint32(5), result)
+}
+
+func TestRandomizer_RangeUint32_MinGreaterThanMax(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.RangeUint32(10, 5)
+	assert.Equal(t, uint32(5), result)
+}
+
+func TestRandomizer_RangeUint32_PositiveRange(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	for i := 0; i < 1000; i++ {
+		result := r.RangeUint32(1, 10)
+		assert.True(t, result >= 1)
+		assert.True(t, result <= 10)
+	}
+}
+
+func TestRandomizer_RangeUint64_MinEqualsMax(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.RangeUint64(5, 5)
+	assert.Equal(t, uint64(5), result)
+}
+
+func TestRandomizer_RangeUint64_MinGreaterThanMax(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.RangeUint64(10, 5)
+	assert.Equal(t, uint64(5), result)
+}
+
+func TestRandomizer_RangeUint64_PositiveRange(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	for i := 0; i < 1000; i++ {
+		result := r.RangeUint64(1, 10)
+		assert.True(t, result >= 1)
+		assert.True(t, result <= 10)
+	}
+}
+
+func TestRandomizer_WeightedChoice_EmptyArray(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.WeightedChoice([]int{})
+	assert.Equal(t, -1, result)
+}
+
+func TestRandomizer_WeightedChoice_AllZeroWeights(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.WeightedChoice([]int{0, 0, 0})
+	assert.Equal(t, 2, result)
+}
+
+func TestRandomizer_WeightedChoice_MixedWeights(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	weightArray := []int{1, 0, 3, 0, 2}
+	counts := make([]int, len(weightArray))
+	for i := 0; i < 1000; i++ {
+		choice := r.WeightedChoice(weightArray)
+		counts[choice]++
+	}
+	assert.Greater(t, counts[0], 0)
+	assert.Greater(t, counts[2], 0)
+	assert.Greater(t, counts[4], 0)
+}
+
+func TestRandomizer_RandomString_LengthZero(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	result := r.RandomString(0)
+	assert.Equal(t, "", result)
+}
+
+func TestRandomizer_RandomString_CorrectLength(t *testing.T) {
+	r := NewRandomizer(UnixNanoSeed)
+	length := 50
+	result := r.RandomString(length)
+	assert.Equal(t, length, len(result))
+}