bigint.js - mozsearch

// Copyright (C) 2017 Josh Wolfe. All rights reserved.

// This code is governed by the BSD license found in the LICENSE file.

/*---

description: Right shift for BigInt values

esid: sec-numeric-types-bigint-signedRightShift

info: |

  BigInt::signedRightShift (x, y)

  The abstract operation BigInt::signedRightShift with arguments x and y of type BigInt:

  1. Return BigInt::leftShift(x, -y).

  sec-numeric-types-bigint-leftShift

  BigInt::leftShift (x, y)

  The abstract operation BigInt::leftShift with two arguments x and y of BigInt:

  1. If y < 0,

    a. Return a BigInt representing x divided by 2-y, rounding down to the nearest integer, including for negative numbers.

  2. Return a BigInt representing x multiplied by 2y.

  NOTE: Semantics here should be equivalent to a bitwise shift, treating the BigInt as an infinite length string of binary two's complement digits.

features: [BigInt]

---*/

assert.sameValue(0n >> 0n, 0n, "0n >> 0n === 0n");

assert.sameValue(0b101n >> -1n, 0b1010n, "0b101n >> -1n === 0b1010n");

assert.sameValue(0b101n >> -2n, 0b10100n, "0b101n >> -2n === 0b10100n");

assert.sameValue(0b101n >> -3n, 0b101000n, "0b101n >> -3n === 0b101000n");

assert.sameValue(0b101n >> 1n, 0b10n, "0b101n >> 1n === 0b10n");

assert.sameValue(0b101n >> 2n, 1n, "0b101n >> 2n === 1n");

assert.sameValue(0b101n >> 3n, 0n, "0b101n >> 3n === 0n");

assert.sameValue(0n >> -128n, 0n, "0n >> -128n === 0n");

assert.sameValue(0n >> 128n, 0n, "0n >> 128n === 0n");

assert.sameValue(0x246n >> 0n, 0x246n, "0x246n >> 0n === 0x246n");

assert.sameValue(0x246n >> -127n, 0x12300000000000000000000000000000000n, "0x246n >> -127n === 0x12300000000000000000000000000000000n");

assert.sameValue(0x246n >> -128n, 0x24600000000000000000000000000000000n, "0x246n >> -128n === 0x24600000000000000000000000000000000n");

assert.sameValue(0x246n >> -129n, 0x48c00000000000000000000000000000000n, "0x246n >> -129n === 0x48c00000000000000000000000000000000n");

assert.sameValue(0x246n >> 128n, 0n, "0x246n >> 128n === 0n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> -64n, 0x123456789abcdef0fedcba98765432123456780000000000000000n,

  "0x123456789abcdef0fedcba9876543212345678n >> -64n === 0x123456789abcdef0fedcba98765432123456780000000000000000n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> -32n, 0x123456789abcdef0fedcba987654321234567800000000n,

  "0x123456789abcdef0fedcba9876543212345678n >> -32n === 0x123456789abcdef0fedcba987654321234567800000000n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> -16n, 0x123456789abcdef0fedcba98765432123456780000n,

  "0x123456789abcdef0fedcba9876543212345678n >> -16n === 0x123456789abcdef0fedcba98765432123456780000n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 0n, 0x123456789abcdef0fedcba9876543212345678n,

  "0x123456789abcdef0fedcba9876543212345678n >> 0n === 0x123456789abcdef0fedcba9876543212345678n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 16n, 0x123456789abcdef0fedcba987654321234n,

  "0x123456789abcdef0fedcba9876543212345678n >> 16n === 0x123456789abcdef0fedcba987654321234n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 32n, 0x123456789abcdef0fedcba98765432n,

  "0x123456789abcdef0fedcba9876543212345678n >> 32n === 0x123456789abcdef0fedcba98765432n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 64n, 0x123456789abcdef0fedcban,

  "0x123456789abcdef0fedcba9876543212345678n >> 64n === 0x123456789abcdef0fedcban");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 127n, 0x2468acn,

  "0x123456789abcdef0fedcba9876543212345678n >> 127n === 0x2468acn");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 128n, 0x123456n,

  "0x123456789abcdef0fedcba9876543212345678n >> 128n === 0x123456n");

assert.sameValue(

  0x123456789abcdef0fedcba9876543212345678n >> 129n, 0x91a2bn,

  "0x123456789abcdef0fedcba9876543212345678n >> 129n === 0x91a2bn");

assert.sameValue(-5n >> -1n, -0xan, "-5n >> -1n === -0xan");

assert.sameValue(-5n >> -2n, -0x14n, "-5n >> -2n === -0x14n");

assert.sameValue(-5n >> -3n, -0x28n, "-5n >> -3n === -0x28n");

assert.sameValue(-5n >> 1n, -3n, "-5n >> 1n === -3n");

assert.sameValue(-5n >> 2n, -2n, "-5n >> 2n === -2n");

assert.sameValue(-5n >> 3n, -1n, "-5n >> 3n === -1n");

assert.sameValue(-1n >> -128n, -0x100000000000000000000000000000000n, "-1n >> -128n === -0x100000000000000000000000000000000n");

assert.sameValue(-1n >> 0n, -1n, "-1n >> 0n === -1n");

assert.sameValue(-1n >> 128n, -1n, "-1n >> 128n === -1n");

assert.sameValue(-0x246n >> 0n, -0x246n, "-0x246n >> 0n === -0x246n");

assert.sameValue(-0x246n >> -127n, -0x12300000000000000000000000000000000n, "-0x246n >> -127n === -0x12300000000000000000000000000000000n");

assert.sameValue(-0x246n >> -128n, -0x24600000000000000000000000000000000n, "-0x246n >> -128n === -0x24600000000000000000000000000000000n");

assert.sameValue(-0x246n >> -129n, -0x48c00000000000000000000000000000000n, "-0x246n >> -129n === -0x48c00000000000000000000000000000000n");

assert.sameValue(-0x246n >> 128n, -1n, "-0x246n >> 128n === -1n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> -64n, -0x123456789abcdef0fedcba98765432123456780000000000000000n,

  "-0x123456789abcdef0fedcba9876543212345678n >> -64n === -0x123456789abcdef0fedcba98765432123456780000000000000000n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> -32n, -0x123456789abcdef0fedcba987654321234567800000000n,

  "-0x123456789abcdef0fedcba9876543212345678n >> -32n === -0x123456789abcdef0fedcba987654321234567800000000n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> -16n, -0x123456789abcdef0fedcba98765432123456780000n,

  "-0x123456789abcdef0fedcba9876543212345678n >> -16n === -0x123456789abcdef0fedcba98765432123456780000n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 0n, -0x123456789abcdef0fedcba9876543212345678n,

  "-0x123456789abcdef0fedcba9876543212345678n >> 0n === -0x123456789abcdef0fedcba9876543212345678n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 16n, -0x123456789abcdef0fedcba987654321235n,

  "-0x123456789abcdef0fedcba9876543212345678n >> 16n === -0x123456789abcdef0fedcba987654321235n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 32n, -0x123456789abcdef0fedcba98765433n,

  "-0x123456789abcdef0fedcba9876543212345678n >> 32n === -0x123456789abcdef0fedcba98765433n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 64n, -0x123456789abcdef0fedcbbn,

  "-0x123456789abcdef0fedcba9876543212345678n >> 64n === -0x123456789abcdef0fedcbbn");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 127n, -0x2468adn,

  "-0x123456789abcdef0fedcba9876543212345678n >> 127n === -0x2468adn");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 128n, -0x123457n,

  "-0x123456789abcdef0fedcba9876543212345678n >> 128n === -0x123457n");

assert.sameValue(

  -0x123456789abcdef0fedcba9876543212345678n >> 129n, -0x91a2cn,

  "-0x123456789abcdef0fedcba9876543212345678n >> 129n === -0x91a2cn");

reportCompare(0, 0);