Files
kjol/tools/tsgo/internal/jsnum/jsnum_test.go
2026-07-09 16:50:43 -04:00

741 lines
18 KiB
Go

package jsnum
import (
"fmt"
"math"
"os"
"path/filepath"
"testing"
"github.com/microsoft/typescript-go/internal/json"
"github.com/microsoft/typescript-go/internal/testutil/jstest"
"gotest.tools/v3/assert"
)
func assertEqualNumber(t *testing.T, got, want Number) {
t.Helper()
if got.IsNaN() || want.IsNaN() {
assert.Equal(t, got.IsNaN(), want.IsNaN(), "got: %v, want: %v", got, want)
} else {
assert.Equal(t, got, want)
}
}
// assertWithinOneULP checks that got and want are either equal or differ by
// at most 1 ULP (unit in the last place).
func assertWithinOneULP(t *testing.T, got, want Number) {
t.Helper()
if got.IsNaN() || want.IsNaN() {
assert.Equal(t, got.IsNaN(), want.IsNaN(), "got: %v, want: %v", got, want)
return
}
if got == want {
return
}
gotBits := math.Float64bits(float64(got))
wantBits := math.Float64bits(float64(want))
if gotBits == wantBits {
return
}
var ulpDist uint64
if gotBits > wantBits {
ulpDist = gotBits - wantBits
} else {
ulpDist = wantBits - gotBits
}
if ulpDist > 1 {
t.Errorf("got %v (%016x), want %v (%016x) within 1 ULP (off by %d ULPs)",
got, gotBits, want, wantBits, ulpDist)
}
}
func numberFromBits(b uint64) Number {
return Number(math.Float64frombits(b))
}
func numberToBits(n Number) uint64 {
return math.Float64bits(float64(n))
}
type binaryInput struct {
X [2]uint32 `json:"x"`
Y [2]uint32 `json:"y"`
}
type binaryResult struct {
X [2]uint32 `json:"x"`
Y [2]uint32 `json:"y"`
Result [2]uint32 `json:"result"`
}
type unaryInput struct {
X [2]uint32 `json:"x"`
}
type unaryResult struct {
X [2]uint32 `json:"x"`
Result [2]uint32 `json:"result"`
}
func numToUint32s(n Number) [2]uint32 {
bits := numberToBits(n)
return [2]uint32{uint32(bits), uint32(bits >> 32)}
}
func uint32sToNum(a [2]uint32) Number {
bits := uint64(a[0]) | uint64(a[1])<<32
return numberFromBits(bits)
}
// evalBinaryOp evaluates a binary JS expression on all cases using Node.js.
// Skips the calling test if Node.js is not available.
func evalBinaryOp(t *testing.T, op string, xs, ys []Number) []Number {
t.Helper()
jstest.SkipIfNoNodeJS(t)
tmpdir := t.TempDir()
inputs := make([]binaryInput, len(xs))
for i := range xs {
inputs[i] = binaryInput{X: numToUint32s(xs[i]), Y: numToUint32s(ys[i])}
}
jsonInput, err := json.Marshal(inputs)
assert.NilError(t, err)
inputPath := filepath.Join(tmpdir, "input.json")
err = os.WriteFile(inputPath, jsonInput, 0o644)
assert.NilError(t, err)
script := fmt.Sprintf(`
import fs from 'fs';
function fromBits(bits) {
const buffer = new ArrayBuffer(8);
(new Uint32Array(buffer))[0] = bits[0];
(new Uint32Array(buffer))[1] = bits[1];
return new Float64Array(buffer)[0];
}
function toBits(number) {
const buffer = new ArrayBuffer(8);
(new Float64Array(buffer))[0] = number;
return [(new Uint32Array(buffer))[0], (new Uint32Array(buffer))[1]];
}
export default function(inputFile) {
const input = JSON.parse(fs.readFileSync(inputFile, 'utf8'));
return input.map(({x, y}) => {
const a = fromBits(x);
const b = fromBits(y);
return { x, y, result: toBits(%s) };
});
};
`, op)
results, err := jstest.EvalNodeScript[[]binaryResult](t, script, tmpdir, inputPath)
assert.NilError(t, err)
assert.Equal(t, len(results), len(xs))
out := make([]Number, len(results))
for i, r := range results {
out[i] = uint32sToNum(r.Result)
}
return out
}
// evalUnaryOp evaluates a unary JS expression on all cases using Node.js.
// Skips the calling test if Node.js is not available.
func evalUnaryOp(t *testing.T, op string, xs []Number) []Number {
t.Helper()
jstest.SkipIfNoNodeJS(t)
tmpdir := t.TempDir()
inputs := make([]unaryInput, len(xs))
for i, x := range xs {
inputs[i] = unaryInput{X: numToUint32s(x)}
}
jsonInput, err := json.Marshal(inputs)
assert.NilError(t, err)
inputPath := filepath.Join(tmpdir, "input.json")
err = os.WriteFile(inputPath, jsonInput, 0o644)
assert.NilError(t, err)
script := fmt.Sprintf(`
import fs from 'fs';
function fromBits(bits) {
const buffer = new ArrayBuffer(8);
(new Uint32Array(buffer))[0] = bits[0];
(new Uint32Array(buffer))[1] = bits[1];
return new Float64Array(buffer)[0];
}
function toBits(number) {
const buffer = new ArrayBuffer(8);
(new Float64Array(buffer))[0] = number;
return [(new Uint32Array(buffer))[0], (new Uint32Array(buffer))[1]];
}
export default function(inputFile) {
const input = JSON.parse(fs.readFileSync(inputFile, 'utf8'));
return input.map(({x}) => {
const a = fromBits(x);
return { x, result: toBits(%s) };
});
};
`, op)
results, err := jstest.EvalNodeScript[[]unaryResult](t, script, tmpdir, inputPath)
assert.NilError(t, err)
assert.Equal(t, len(results), len(xs))
out := make([]Number, len(results))
for i, r := range results {
out[i] = uint32sToNum(r.Result)
}
return out
}
var toInt32Tests = []struct {
name string
input Number
want int32
bench bool
}{
{"0.0", 0, 0, true},
{"-0.0", Number(negativeZero), 0, false},
{"NaN", NaN(), 0, true},
{"+Inf", Inf(1), 0, true},
{"-Inf", Inf(-1), 0, true},
{"MaxInt32", Number(math.MaxInt32), math.MaxInt32, false},
{"MaxInt32+1", Number(int64(math.MaxInt32) + 1), math.MinInt32, true},
{"MinInt32", Number(math.MinInt32), math.MinInt32, false},
{"MinInt32-1", Number(int64(math.MinInt32) - 1), math.MaxInt32, true},
{"MIN_SAFE_INTEGER", MinSafeInteger, 1, false},
{"MIN_SAFE_INTEGER-1", MinSafeInteger - 1, 0, false},
{"MIN_SAFE_INTEGER+1", MinSafeInteger + 1, 2, false},
{"MAX_SAFE_INTEGER", MaxSafeInteger, -1, true},
{"MAX_SAFE_INTEGER-1", MaxSafeInteger - 1, -2, true},
{"MAX_SAFE_INTEGER+1", MaxSafeInteger + 1, 0, true},
{"-8589934590", -8589934590, 2, false},
{"0xDEADBEEF", 0xDEADBEEF, -559038737, true},
{"4294967808", 4294967808, 512, false},
{"-0.4", -0.4, 0, false},
{"SmallestNonzeroFloat64", math.SmallestNonzeroFloat64, 0, false},
{"-SmallestNonzeroFloat64", -math.SmallestNonzeroFloat64, 0, false},
{"MaxFloat64", math.MaxFloat64, 0, false},
{"-MaxFloat64", -math.MaxFloat64, 0, false},
{"Largest subnormal number", numberFromBits(0x000FFFFFFFFFFFFF), 0, false},
{"Smallest positive normal number", numberFromBits(0x0010000000000000), 0, false},
{"Largest normal number", math.MaxFloat64, 0, false},
{"-Largest normal number", -math.MaxFloat64, 0, false},
{"1.0", 1.0, 1, false},
{"-1.0", -1.0, -1, false},
{"1e308", 1e308, 0, false},
{"-1e308", -1e308, 0, false},
{"math.Pi", math.Pi, 3, false},
{"-math.Pi", -math.Pi, -3, false},
{"math.E", math.E, 2, false},
{"-math.E", -math.E, -2, false},
{"0.5", 0.5, 0, false},
{"-0.5", -0.5, 0, false},
{"0.49999999999999994", 0.49999999999999994, 0, false},
{"-0.49999999999999994", -0.49999999999999994, 0, false},
{"0.5000000000000001", 0.5000000000000001, 0, false},
{"-0.5000000000000001", -0.5000000000000001, 0, false},
{"2^31 + 0.5", 2147483648.5, -2147483648, false},
{"-2^31 - 0.5", -2147483648.5, -2147483648, false},
{"2^40", 1099511627776, 0, false},
{"-2^40", -1099511627776, 0, false},
{"TypeFlagsNarrowable", 536624127, 536624127, true},
}
func TestToInt32(t *testing.T) {
t.Parallel()
inputs := make([]Number, len(toInt32Tests))
zeros := make([]Number, len(toInt32Tests))
for i, test := range toInt32Tests {
inputs[i] = test.input
}
for _, test := range toInt32Tests {
t.Run(fmt.Sprintf("%s (%v)", test.name, float64(test.input)), func(t *testing.T) {
t.Parallel()
got := test.input.toInt32()
assert.Equal(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a | b", inputs, zeros)
for i, test := range toInt32Tests {
t.Run(fmt.Sprintf("%s (%v)", test.name, float64(test.input)), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, Number(test.input.toInt32()), jsResults[i])
})
}
})
}
func BenchmarkToInt32(b *testing.B) {
for _, test := range toInt32Tests {
if !test.bench {
continue
}
b.Run(fmt.Sprintf("%s (%v)", test.name, float64(test.input)), func(b *testing.B) {
for b.Loop() {
test.input.toInt32()
}
})
}
}
func TestBitwiseNOT(t *testing.T) {
t.Parallel()
tests := []struct {
x, want Number
}{
// Original pairs: ~(-2147483649) == ~(2147483647)
{Number(-2147483649), -2147483648},
{Number(2147483647), -2147483648},
// Original pairs: ~(-4294967296) == ~(0)
{Number(-4294967296), -1},
{0, -1},
// Original pairs: ~(2147483648) == ~(-2147483648)
{Number(2147483648), 2147483647},
{Number(-2147483648), 2147483647},
// Original pairs: ~(4294967296) == ~(0)
{Number(4294967296), -1},
}
xs := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
}
for _, test := range tests {
t.Run(fmt.Sprintf("~%v", test.x), func(t *testing.T) {
t.Parallel()
got := test.x.BitwiseNOT()
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalUnaryOp(t, "~a", xs)
for i, test := range tests {
t.Run(fmt.Sprintf("~%v", test.x), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.BitwiseNOT(), jsResults[i])
})
}
})
}
func TestBitwiseAND(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{0, 0, 0},
{0, 1, 0},
{1, 0, 0},
{1, 1, 1},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v & %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.BitwiseAND(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a & b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v & %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.BitwiseAND(test.y), jsResults[i])
})
}
})
}
func TestBitwiseOR(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{0, 0, 0},
{0, 1, 1},
{1, 0, 1},
{1, 1, 1},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v | %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.BitwiseOR(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a | b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v | %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.BitwiseOR(test.y), jsResults[i])
})
}
})
}
func TestBitwiseXOR(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{0, 0, 0},
{0, 1, 1},
{1, 0, 1},
{1, 1, 0},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v ^ %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.BitwiseXOR(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a ^ b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v ^ %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.BitwiseXOR(test.y), jsResults[i])
})
}
})
}
func TestSignedRightShift(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{1, 0, 1},
{1, 1, 0},
{1, 2, 0},
{1, 31, 0},
{1, 32, 1},
{-4, 0, -4},
{-4, 1, -2},
{-4, 2, -1},
{-4, 3, -1},
{-4, 4, -1},
{-4, 31, -1},
{-4, 32, -4},
{-4, 33, -2},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v >> %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.SignedRightShift(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a >> b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v >> %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.SignedRightShift(test.y), jsResults[i])
})
}
})
}
func TestUnsignedRightShift(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{1, 0, 1},
{1, 1, 0},
{1, 2, 0},
{1, 31, 0},
{1, 32, 1},
{-4, 0, 4294967292},
{-4, 1, 2147483646},
{-4, 2, 1073741823},
{-4, 3, 536870911},
{-4, 4, 268435455},
{-4, 31, 1},
{-4, 32, 4294967292},
{-4, 33, 2147483646},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v >>> %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.UnsignedRightShift(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a >>> b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v >>> %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.UnsignedRightShift(test.y), jsResults[i])
})
}
})
}
func TestLeftShift(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{1, 0, 1},
{1, 1, 2},
{1, 2, 4},
{1, 31, -2147483648},
{1, 32, 1},
{-4, 0, -4},
{-4, 1, -8},
{-4, 2, -16},
{-4, 3, -32},
{-4, 31, 0},
{-4, 32, -4},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v << %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.LeftShift(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a << b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v << %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.LeftShift(test.y), jsResults[i])
})
}
})
}
func TestRemainder(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{NaN(), 1, NaN()},
{1, NaN(), NaN()},
{Inf(1), 1, NaN()},
{Inf(-1), 1, NaN()},
{123, Inf(1), 123},
{123, Inf(-1), 123},
{123, 0, NaN()},
{123, negativeZero, NaN()},
{0, 123, 0},
{negativeZero, 123, negativeZero},
// Normal cases
{10, 3, 1},
{-10, 3, -1},
{10, -3, 1},
{-10, -3, -1},
{5.5, 2, 1.5},
{-5.5, 2, -1.5},
{1, 0.5, 0},
{-1, 0.5, negativeZero},
{1.5, 1, 0.5},
{-1.5, 1, -0.5},
// Edge cases that prove the bug in the manual formula:
// The manual formula n - d*(n/d).trunc() accumulates floating-point
// rounding errors that IEEE 754 fmod (math.Mod) avoids.
{7, 0.1, Number(math.Mod(7, 0.1))},
{7, 0.2, Number(math.Mod(7, 0.2))},
{7, 0.3, Number(math.Mod(7, 0.3))},
{100, 0.3, Number(math.Mod(100, 0.3))},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v %% %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.Remainder(test.y)
assertEqualNumber(t, got, test.want)
})
}
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a % b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v %% %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertEqualNumber(t, test.x.Remainder(test.y), jsResults[i])
})
}
})
}
func TestExponentiate(t *testing.T) {
t.Parallel()
tests := []struct {
x, y, want Number
}{
{2, 3, 8},
{Inf(1), 3, Inf(1)},
{Inf(1), -5, 0},
{Inf(-1), 3, Inf(-1)},
{Inf(-1), 4, Inf(1)},
{Inf(-1), -3, negativeZero},
{Inf(-1), -4, 0},
{0, 3, 0},
{0, -10, Inf(1)},
{negativeZero, 3, negativeZero},
{negativeZero, 4, 0},
{negativeZero, -3, Inf(-1)},
{negativeZero, -4, Inf(1)},
{3, Inf(1), Inf(1)},
{-3, Inf(1), Inf(1)},
{3, Inf(-1), 0},
{-3, Inf(-1), 0},
{NaN(), 3, NaN()},
{1, Inf(1), NaN()},
{1, Inf(-1), NaN()},
{-1, Inf(1), NaN()},
{-1, Inf(-1), NaN()},
{1, NaN(), NaN()},
// Cases where math.Pow diverges from V8 by >1 ULP.
// Expected values are the correctly-rounded IEEE 754 results
// computed via exact integer arithmetic (big.Int).
// Cross-engine testing (V8, SpiderMonkey, QuickJS, XS via jsvu)
// confirmed these match the majority of JS engines.
{10, 308, numberFromBits(0x7fe1ccf385ebc8a0)},
{5, 210, numberFromBits(0x5e68557f31326bbb)},
{10, 200, numberFromBits(0x6974e718d7d7625a)},
}
xs := make([]Number, len(tests))
ys := make([]Number, len(tests))
for i, test := range tests {
xs[i] = test.x
ys[i] = test.y
}
for _, test := range tests {
t.Run(fmt.Sprintf("%v ** %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
got := test.x.Exponentiate(test.y)
assertEqualNumber(t, got, test.want)
})
}
// The ES spec says exponentiate is "implementation-approximated".
// Different JS engines (V8, SpiderMonkey, JSC) use different pow
// implementations that can differ by 1 ULP. Allow that tolerance.
t.Run("Node", func(t *testing.T) {
jsResults := evalBinaryOp(t, "a ** b", xs, ys)
for i, test := range tests {
t.Run(fmt.Sprintf("%v ** %v", test.x, test.y), func(t *testing.T) {
t.Parallel()
assertWithinOneULP(t, test.x.Exponentiate(test.y), jsResults[i])
})
}
})
}
func BenchmarkExponentiate(b *testing.B) {
cases := []struct {
name string
base Number
exponent Number
}{
{"2**10_exact", 2, 10}, // small, fits in 53 bits → math.Pow
{"2**53_exact", 2, 53}, // boundary, exactly 53 bits → math.Pow
{"10**20_bigint", 10, 20}, // exceeds 53 bits → big.Int
{"10**308_bigint", 10, 308}, // large exponent → big.Int
{"3**34_bigint", 3, 34}, // medium → big.Int
{"0.5**-0.5_mathpow", 0.5, -0.5}, // non-integer → math.Pow
}
for _, c := range cases {
b.Run(c.name, func(b *testing.B) {
for b.Loop() {
c.base.Exponentiate(c.exponent)
}
})
}
}