Function TestRandom

map_test.go:287–346

(t *testing.T)

}

func TestRandom(t *testing.T) {
	test := func(t *testing.T, m *Map[int, int]) {
		e := make(map[int]int)
		for i := 0; i < 10000; i++ {
			switch r := rand.Float64(); {
			case r < 0.5: // 50% inserts
				k, v := rand.Int(), rand.Int()
				m.Put(k, v)
				e[k] = v
			case r < 0.65: // 15% updates
				if k, _, ok := m.randElement(); !ok {
					require.EqualValues(t, 0, m.Len(), e)
				} else {
					v := rand.Int()
					m.Put(k, v)
					e[k] = v
				}
			case r < 0.80: // 15% deletes
				if k, _, ok := m.randElement(); !ok {
					require.EqualValues(t, 0, m.Len(), e)
				} else {
					m.Delete(k)
					delete(e, k)
				}
			case r < 0.95: // 25% lookups
				if k, v, ok := m.randElement(); !ok {
					require.EqualValues(t, 0, m.Len(), e)
				} else {
					require.EqualValues(t, e[k], v)
				}
			default: // 5% rehash in place and iterate
				i := rand.Intn(int(m.bucketCount()))
				m.dir.At(uintptr(i)).rehashInPlace(m)
				require.Equal(t, e, m.toBuiltinMap())
			}
			require.EqualValues(t, len(e), m.Len())
		}
	}

	t.Run("normal", func(t *testing.T) {
		test(t, New[int, int](0))
	})

	t.Run("degenerate", func(t *testing.T) {
		testDegenerate := func(t *testing.T, h uintptr) {
			m := New[int, int](0,
				WithHash[int, int](func(key *int, seed uintptr) uintptr {
					return h
				}),
				WithMaxBucketCapacity[int, int](512))
			test(t, m)
		}

		for _, v := range []uintptr{0, ^uintptr(0)} {
			t.Run(fmt.Sprintf("%016x", v), func(t *testing.T) {
				testDegenerate(t, v)
			})
		}