tests: add tests to go/vt/vtgate/semantics/bitset (#15049)

Signed-off-by: Manik Rana <[email protected]>

go/vt/vtgate/semantics/bitset/bitset_test.go

@@ -19,6 +19,7 @@ package bitset
 import (
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
@@ -38,3 +39,335 @@ func TestSingletons(t *testing.T) {
 		require.True(t, called)
 	}
 }
+
+func TestSingleBitReturnsNegativeOne(t *testing.T) {
+	bs := Bitset("\x0F")
+	result := bs.SingleBit()
+
+	assert.Equal(t, -1, result)
+}
+
+func TestToBitsetPanic(t *testing.T) {
+	defer func() {
+		if r := recover(); r == nil {
+			require.NotNil(t, r, "Expected panic, but none occurred")
+		}
+	}()
+
+	byteEndsWithZero := []byte{8, 0}
+
+	_ = toBitset(byteEndsWithZero)
+}
+
+func TestBuild(t *testing.T) {
+	tt := []struct {
+		name string
+		bits []int
+		want Bitset
+	}{
+		{"Empty Bits", []int{}, ""},
+		{"Single Bit", []int{3}, "\x08"},
+		{"Multiple Bits", []int{1, 3, 5, 7}, "\xAA"},
+		{"Large Bits", []int{10, 11, 12}, "\x00\x1C"},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := Build(tc.bits...)
+			assert.Equal(t, tc.want, got)
+		})
+	}
+}
+
+func TestAnd(t *testing.T) {
+	tt := []struct {
+		name     string
+		bs1, bs2 Bitset
+		expected Bitset
+	}{
+		{
+			name:     "Two NonEmpty",
+			bs1:      Build(1, 2, 3, 4, 5),
+			bs2:      Build(3, 4, 5, 6, 7),
+			expected: Build(3, 4, 5),
+		},
+		{
+			name:     "One Empty",
+			bs1:      Build(1, 2, 3, 4, 5),
+			bs2:      Build(),
+			expected: "",
+		},
+		{
+			name:     "Both Empty",
+			bs1:      Build(),
+			bs2:      Build(),
+			expected: "",
+		},
+		{
+			name:     "Different Word Sizes",
+			bs1:      Build(1, 2, 3, 4, 5, 33),
+			bs2:      Build(3, 4, 5, 6, 7),
+			expected: Build(3, 4, 5),
+		},
+		{
+			name:     "One Empty One NonEmpty",
+			bs1:      Build(),
+			bs2:      Build(3, 4, 5, 6, 7),
+			expected: "",
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			result := tc.bs1.And(tc.bs2)
+			require.Equal(t, tc.expected, result)
+		})
+	}
+}
+
+func TestAndNot(t *testing.T) {
+	tt := []struct {
+		name   string
+		bs1    Bitset
+		bs2    Bitset
+		result Bitset
+	}{
+		{
+			"Empty AndNot Empty",
+			"",
+			Build(1, 2, 3),
+			"",
+		},
+		{
+			"NonEmpty And Empty",
+			Build(1, 2, 3),
+			"",
+			Build(1, 2, 3),
+		},
+		{
+			"NonEmpty And NotEmpty",
+			Build(1, 2, 3),
+			Build(2, 3, 4),
+			Build(1),
+		},
+		{
+			"Common BitsSet AndNot",
+			Build(1, 2, 3, 4, 5, 6, 7, 8),
+			Build(3, 4, 5, 6, 7, 8, 9, 10),
+			Build(1, 2),
+		},
+		{
+			"bs1 Greater than bs2",
+			Build(1, 2, 3, 4, 5, 6, 7, 8),
+			Build(2, 3, 4),
+			Build(1, 5, 6, 7, 8),
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.bs1.AndNot(tc.bs2)
+			assert.Equal(t, tc.result, got)
+		})
+	}
+}
+
+func TestOr(t *testing.T) {
+	tt := []struct {
+		name   string
+		bs1    Bitset
+		bs2    Bitset
+		result Bitset
+	}{
+		{
+			"Empty Or Empty",
+			"",
+			"",
+			"",
+		},
+		{
+			"Empty Or NonEmpty",
+			"",
+			Build(1, 2, 3),
+			Build(1, 2, 3),
+		},
+		{
+			"NonEmpty Or Empty",
+			Build(1, 2, 3),
+			"",
+			Build(1, 2, 3),
+		},
+		{
+			"NonEmpty Or NonEmpty",
+			Build(1, 2, 3),
+			Build(4, 5, 6),
+			Build(1, 2, 3, 4, 5, 6),
+		},
+		{
+			"Common BitsSet",
+			Build(1, 2, 3, 4),
+			Build(3, 4, 5, 6),
+			Build(1, 2, 3, 4, 5, 6),
+		},
+		{
+			"Bs1 Larger Than Bs2",
+			Build(3, 4, 5, 6, 7, 8, 9, 10),
+			Build(1, 2),
+			Build(1, 2, 3, 4, 5, 6, 7, 8, 9, 10),
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.bs1.Or(tc.bs2)
+			assert.Equal(t, tc.result, got)
+		})
+	}
+}
+
+func TestSet(t *testing.T) {
+	tt := []struct {
+		name   string
+		bs     Bitset
+		offset int
+		result Bitset
+	}{
+		{
+			"Set On Empty Bitset",
+			"",
+			3,
+			Build(3),
+		},
+		{
+			"Set On NonEmpty Bitset",
+			Build(1, 2, 3),
+			10,
+			Build(1, 2, 3, 10),
+		},
+		{
+			"Set On Existing Bit",
+			Build(1, 2, 3, 4),
+			3,
+			Build(1, 2, 3, 4),
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.bs.Set(tc.offset)
+			assert.Equal(t, tc.result, got)
+		})
+	}
+}
+
+func TestIsContainedBy(t *testing.T) {
+	tt := []struct {
+		name     string
+		bs1      Bitset
+		bs2      Bitset
+		expected bool
+	}{
+		{
+			"Empty Is Contained By Empty",
+			"",
+			"",
+			true,
+		},
+		{
+			"Empty Is Contained By NonEmpty",
+			"",
+			Build(1, 2, 3),
+			true,
+		},
+		{
+			"NonEmpty Is Contained By Empty",
+			Build(1, 2, 3),
+			"",
+			false,
+		},
+		{
+			"Subset Is Contained By Superset",
+			Build(1, 2, 3),
+			Build(1, 2, 3, 4, 5, 6),
+			true,
+		},
+		{
+			"Not Contained",
+			Build(1, 2, 3),
+			Build(4, 5, 6),
+			false,
+		},
+		{
+			"Equal Bitsets",
+			Build(1, 2, 3),
+			Build(1, 2, 3),
+			true,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.bs1.IsContainedBy(tc.bs2)
+			assert.Equal(t, tc.expected, got)
+		})
+	}
+}
+
+func TestOverlaps(t *testing.T) {
+	tt := []struct {
+		name     string
+		bs1      Bitset
+		bs2      Bitset
+		expected bool
+	}{
+		{
+			"Empty Does Not Overlap Empty",
+			"",
+			"",
+			false,
+		},
+		{
+			"Empty Does Not Overlap NonEmpty",
+			"",
+			Build(1, 2, 3),
+			false,
+		},
+		{
+			"NonEmpty Does Not Overlap Empty",
+			Build(1, 2, 3),
+			"",
+			false,
+		},
+		{
+			"Common Bits Overlap",
+			Build(1, 2, 3, 4),
+			Build(3, 4, 5, 6),
+			true,
+		},
+		{
+			"No Common Bits Do Not Overlap",
+			Build(1, 2, 3, 4),
+			Build(5, 6, 7, 8),
+			false,
+		},
+		{
+			"Partial Overlap",
+			Build(1, 2, 3, 4, 5),
+			Build(4, 5, 6),
+			true,
+		},
+		{
+			"Equal Bitsets Overlap",
+			Build(1, 2, 3),
+			Build(1, 2, 3),
+			true,
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.bs1.Overlaps(tc.bs2)
+			assert.Equal(t, tc.expected, got)
+		})
+	}
+}