deep-equal/test/cmp.js

'use strict';

var test = require('tape');
require('./_tape');
var assign = require('object.assign');
var gOPDs = require('object.getownpropertydescriptors');
var hasSymbols = require('has-symbols')();
var hasTypedArrays = require('has-typed-arrays')();
var semver = require('semver');

var safeBuffer = typeof Buffer === 'function' ? Buffer.from && Buffer.from.length > 1 ? Buffer.from : Buffer : null;
var buffersAreTypedArrays = typeof Buffer === 'function' && new Buffer(0) instanceof Uint8Array;

var isNode = typeof process === 'object' && typeof process.version === 'string';

function tag(obj, value) {
  if (hasSymbols && Symbol.toStringTag && Object.defineProperty) {
    Object.defineProperty(obj, Symbol.toStringTag, {
      value: value
    });
  }
  return obj;
}

// eslint-disable-next-line no-proto
var hasDunderProto = [].__proto__ === Array.prototype;

test('equal', function (t) {
  t.deepEqualTest(
    { a: [2, 3], b: [4] },
    { a: [2, 3], b: [4] },
    'two equal objects',
    true,
    true,
    false
  );

  t.deepEqualTest(
    { a: 2, b: '4' },
    { a: 2, b: 4 },
    'two loosely equal, strictly inequal objects',
    true,
    false
  );

  t.deepEqualTest(
    { a: 2, b: 4 },
    { a: 2, B: 4 },
    'two inequal objects',
    false,
    false
  );

  t.deepEqualTest(
    '-000',
    false,
    '`false` and `"-000"`',
    true,
    false
  );

  t.end();
});

test('Maps', { skip: typeof Map !== 'function' }, function (t) {
  t.deepEqualTest(
    new Map([['a', 1], ['b', 2]]),
    new Map([['b', 2], ['a', 1]]),
    'two equal Maps',
    true,
    true
  );

  t.deepEqualTest(
    new Map([['a', [1, 2]]]),
    new Map([['a', [2, 1]]]),
    'two Maps with inequal values on the same key',
    false,
    false
  );

  t.deepEqualTest(
    new Map([['a', 1]]),
    new Map([['b', 1]]),
    'two inequal Maps',
    false,
    false
  );

  t.deepEqualTest(
    new Map([[{}, 3], [{}, 2], [{}, 1]]),
    new Map([[{}, 1], [{}, 2], [{}, 3]]),
    'two equal Maps in different orders with object keys',
    true,
    true
  );

  t.deepEqualTest(
    new Map([[undefined, undefined]]),
    new Map([[undefined, null]]),
    'undefined keys, nullish values, loosely equal, strictly inequal',
    true,
    false
  );

  t.deepEqualTest(
    new Map([[{}, null], [true, 2], [{}, 1], [undefined, {}]]),
    new Map([[{}, 1], [true, 2], [{}, null], [undefined, {}]]),
    'two equal Maps in different orders with primitive keys',
    true,
    true
  );

  t.deepEqualTest(
    new Map([[false, 3], [{}, 2], [{}, 1]]),
    new Map([[{}, 1], [{}, 2], [false, 3]]),
    'two equal Maps in different orders with a mix of keys',
    true,
    true
  );

  t.deepEqualTest(
    new Map([[null, undefined]]),
    new Map([[null, null]]),
    'null keys, nullish values, loosely equal, strictly inequal',
    true,
    false
  );

  t.deepEqualTest(
    new Map([[undefined, 3]]),
    new Map([[null, 3]]),
    'nullish keys, loosely equal, strictly inequal',
    true,
    false
  );

  t.deepEqualTest(
    new Map([[{}, null], [true, 2], [{}, 1], [undefined, {}]]),
    new Map([[{}, 1], [true, 2], [{}, null], [undefined, {}]]),
    'two equal Maps in different orders with primitive keys',
    true,
    true
  );

  t.deepEqualTest(
    new Map([[false, 3], [{}, 2], [{}, 1]]),
    new Map([[{}, 1], [{}, 2], [false, 3]]),
    'two equal Maps in different orders with a mix of keys',
    true,
    true
  );

  t.deepEqualTest(
    new Map(),
    new Map([[{}, 1]]),
    'two inequal Maps',
    false,
    false
  );

  t.deepEqualTest(
    new Map([[{}, null], [false, 3]]),
    new Map([[{}, null], [true, 2]]),
    'two inequal maps, same size, primitive key, start with object key',
    false,
    false
  );

  t.deepEqualTest(
    new Map([[false, 3], [{}, null]]),
    new Map([[true, 2], [{}, null]]),
    'two inequal maps, same size, primitive key, start with primitive key',
    false,
    false
  );

  t.deepEqualTest(
    new Map([[undefined, null], ['+000', 2]]),
    new Map([[null, undefined], [false, '2']]),
    'primitive comparisons',
    true,
    false
  );

  t.end();
});

test('WeakMaps', { skip: typeof WeakMap !== 'function' }, function (t) {
  t.deepEqualTest(
    new WeakMap([[Object, null], [Function, true]]),
    new WeakMap([[Function, true], [Object, null]]),
    'two equal WeakMaps',
    true,
    true
  );

  t.deepEqualTest(
    new WeakMap([[Object, null]]),
    new WeakMap([[Object, true]]),
    'two WeakMaps with inequal values on the same key',
    true,
    true
  );

  t.deepEqualTest(
    new WeakMap([[Object, null], [Function, true]]),
    new WeakMap([[Object, null]]),
    'two inequal WeakMaps',
    true,
    true
  );

  t.end();
});

test('Sets', { skip: typeof Set !== 'function' }, function (t) {
  t.deepEqualTest(
    new Set(['a', 1, 'b', 2]),
    new Set(['b', 2, 'a', 1]),
    'two equal Sets',
    true,
    true
  );

  t.deepEqualTest(
    new Set(['a', 1]),
    new Set(['b', 1]),
    'two inequal Sets',
    false,
    false
  );

  t.deepEqualTest(
    new Set([{}, 1, {}, {}, 2]),
    new Set([{}, 1, {}, 2, {}]),
    'two equal Sets in different orders',
    true,
    true
  );

  t.deepEqualTest(
    new Set(),
    new Set([1]),
    'two inequally sized Sets',
    false,
    false
  );

  t.deepEqualTest(
    new Set([{ a: 1 }, 2]),
    new Set(['2', { a: '1' }]),
    'two loosely equal, strictly inequal Sets',
    true,
    false
  );

  t.deepEqualTest(
    new Set([{ a: 1 }, 2]),
    new Set(['2', { a: 2 }]),
    'two inequal Sets',
    false,
    false
  );

  t.deepEqualTest(
    new Set([null, '', 1, 5, 2, false]),
    new Set([undefined, 0, '5', true, '2', '-000']),
    'more primitive comparisons',
    true,
    false
  );

  t.end();
});

test('Set and Map', { skip: !Object.defineProperty || typeof Set !== 'function' || typeof Map !== 'function' }, function (t) {
  t.deepEqualTest(
    new Set(),
    new Map(),
    'Map and Set',
    false,
    false
  );

  var maplikeSet = new Set();
  Object.defineProperty(maplikeSet, 'constructor', { enumerable: false, value: Map });
  maplikeSet.__proto__ = Map.prototype; // eslint-disable-line no-proto
  t.deepEqualTest(
    maplikeSet,
    new Map(),
    'Map-like Set, and Map',
    false,
    false
  );

  t.end();
});

test('WeakSets', { skip: typeof WeakSet !== 'function' }, function (t) {
  t.deepEqualTest(
    new WeakSet([Object, Function]),
    new WeakSet([Function, Object]),
    'two equal WeakSets',
    true,
    true
  );

  t.deepEqualTest(
    new WeakSet([Object, Function]),
    new WeakSet([Object]),
    'two inequal WeakSets',
    true,
    true
  );

  t.end();
});

test('not equal', function (t) {
  t.deepEqualTest(
    { x: 5, y: [6] },
    { x: 5, y: 6 },
    'two inequal objects are',
    false,
    false
  );

  t.end();
});

test('nested nulls', function (t) {
  t.deepEqualTest(
    [null, null, null],
    [null, null, null],
    'same-length arrays of nulls',
    true,
    true,
    true
  );
  t.end();
});

test('objects with strings vs numbers', function (t) {
  t.deepEqualTest(
    [{ a: 3 }, { b: 4 }],
    [{ a: '3' }, { b: '4' }],
    'objects with equivalent string/number values',
    true,
    false
  );
  t.end();
});

test('non-objects', function (t) {
  t.deepEqualTest(3, 3, 'same numbers', true, true, true);
  t.deepEqualTest('beep', 'beep', 'same strings', true, true, true);
  t.deepEqualTest('3', 3, 'numeric string and number', true, false);
  t.deepEqualTest('3', [3], 'numeric string and array containing number', false, false);
  t.deepEqualTest(3, [3], 'number and array containing number', false, false);

  t.end();
});

test('infinities', function (t) {
  t.deepEqualTest(Infinity, Infinity, '∞ and ∞', true, true, true);
  t.deepEqualTest(-Infinity, -Infinity, '-∞ and -∞', true, true, true);
  t.deepEqualTest(Infinity, -Infinity, '∞ and -∞', false, false);

  t.end();
});

test('arguments class', function (t) {
  function getArgs() {
    return arguments;
  }

  t.deepEqualTest(
    getArgs(1, 2, 3),
    getArgs(1, 2, 3),
    'equivalent arguments objects are equal',
    true,
    true,
    true
  );

  t.deepEqualTest(
    getArgs(1, 2, 3),
    [1, 2, 3],
    'array and arguments with same contents',
    false,
    false
  );

  var args = getArgs();
  var notArgs = tag({ length: 0 }, 'Arguments');
  t.deepEqualTest(
    args,
    notArgs,
    'args and similar arraylike object',
    false,
    false
  );

  t.end();
});

test('Dates', function (t) {
  var d0 = new Date(1387585278000);
  var d1 = new Date('Fri Dec 20 2013 16:21:18 GMT-0800 (PST)');

  t.deepEqualTest(d0, d1, 'two Dates with the same timestamp', true, true);

  d1.a = true;

  t.deepEqualTest(d0, d1, 'two Dates with the same timestamp but different own properties', false, false);

  t.test('overriding `getTime`', { skip: !Object.defineProperty }, function (st) {
    var a = new Date('2000');
    var b = new Date('2000');
    Object.defineProperty(a, 'getTime', { value: function () { return 5; } });
    st.deepEqualTest(a, b, 'two Dates with the same timestamp but one has overridden `getTime`', true, true);
    st.end();
  });

  t.test('fake Date', { skip: !hasDunderProto }, function (st) {
    var a = new Date(2000);
    var b = tag(Object.create(
      a.__proto__, // eslint-disable-line no-proto
      gOPDs(a)
    ), 'Date');

    st.deepEqualTest(
      a,
      b,
      'Date, and fake Date',
      false,
      false
    );

    st.end();
  });

  var a = new Date('2000');
  var b = new Date('2000');
  b.foo = true;
  t.deepEqualTest(
    a,
    b,
    'two identical Dates, one with an extra property',
    false,
    false
  );

  t.deepEqualTest(
    new Date('2000'),
    new Date('2001'),
    'two inequal Dates',
    false,
    false
  );

  t.end();
});

test('buffers', { skip: typeof Buffer !== 'function' }, function (t) {
  /* eslint no-buffer-constructor: 1, new-cap: 1 */
  t.deepEqualTest(
    safeBuffer('xyz'),
    safeBuffer('xyz'),
    'buffers with same contents are equal',
    true,
    true
  );

  t.deepEqualTest(
    safeBuffer('xyz'),
    safeBuffer('xyy'),
    'buffers with same length and different contents are inequal',
    false,
    false
  );

  t.deepEqualTest(
    safeBuffer('xyz'),
    safeBuffer('xy'),
    'buffers with different length are inequal',
    false,
    false
  );

  t.deepEqualTest(
    safeBuffer('abc'),
    safeBuffer('xyz'),
    'buffers with different contents',
    false,
    false
  );

  var emptyBuffer = safeBuffer('');

  t.deepEqualTest(
    emptyBuffer,
    [],
    'empty buffer and empty array',
    false,
    false
  );

  t.test('bufferlikes', { skip: !Object.defineProperty || !hasTypedArrays }, function (st) {
    var fakeBuffer = {
      0: 'a',
      length: 1,
      __proto__: emptyBuffer.__proto__, // eslint-disable-line no-proto
      copy: emptyBuffer.copy,
      slice: emptyBuffer.slice
    };
    Object.defineProperty(fakeBuffer, '0', { enumerable: false });
    Object.defineProperty(fakeBuffer, 'length', { enumerable: false });
    Object.defineProperty(fakeBuffer, 'copy', { enumerable: false });
    Object.defineProperty(fakeBuffer, 'slice', { enumerable: false });

    st.deepEqualTest(
      safeBuffer('a'),
      fakeBuffer,
      'real buffer, and mildly fake buffer',
      false,
      false
    );

    st.test('bufferlike', { skip: buffersAreTypedArrays ? !hasSymbols || !Symbol.toStringTag : false }, function (s2t) {
      var bufferlike = buffersAreTypedArrays ? new Uint8Array() : {};
      Object.defineProperty(bufferlike, 'length', {
        enumerable: false,
        value: bufferlike.length || 0
      });
      Object.defineProperty(bufferlike, 'copy', {
        enumerable: false,
        value: emptyBuffer.copy
      });
      bufferlike.__proto__ = emptyBuffer.__proto__; // eslint-disable-line no-proto

      s2t.deepEqualTest(
        emptyBuffer,
        bufferlike,
        'empty buffer and empty bufferlike',
        true,
        true
      );
      s2t.end();
    });

    st.end();
  });

  t.end();
});

test('Arrays', function (t) {
  var a = [];
  var b = [];
  b.foo = true;

  t.deepEqualTest(
    a,
    b,
    'two identical arrays, one with an extra property',
    false,
    false
  );

  t.end();
});

test('booleans', function (t) {
  t.deepEqualTest(
    true,
    true,
    'trues',
    true,
    true,
    false
  );

  t.deepEqualTest(
    false,
    false,
    'falses',
    true,
    true,
    false
  );

  t.deepEqualTest(
    true,
    false,
    'true and false',
    false,
    false
  );

  t.end();
});

test('booleans and arrays', function (t) {
  t.deepEqualTest(
    true,
    [],
    'true and an empty array',
    false,
    false
  );
  t.deepEqualTest(
    false,
    [],
    'false and an empty array',
    false,
    false
  );
  t.end();
});

test('arrays initiated', function (t) {
  var a0 = [
    undefined,
    null,
    -1,
    0,
    1,
    false,
    true,
    undefined,
    '',
    'abc',
    null,
    undefined
  ];
  var a1 = [
    undefined,
    null,
    -1,
    0,
    1,
    false,
    true,
    undefined,
    '',
    'abc',
    null,
    undefined
  ];

  t.deepEqualTest(
    a0,
    a1,
    'arrays with equal contents are equal',
    true,
    true,
    true
  );
  t.end();
});

test('arrays assigned', function (t) {
  var a0 = [
    undefined,
    null,
    -1,
    0,
    1,
    false,
    true,
    undefined,
    '',
    'abc',
    null,
    undefined
  ];
  var a1 = [];

  a1[0] = undefined;
  a1[1] = null;
  a1[2] = -1;
  a1[3] = 0;
  a1[4] = 1;
  a1[5] = false;
  a1[6] = true;
  a1[7] = undefined;
  a1[8] = '';
  a1[9] = 'abc';
  a1[10] = null;
  a1[11] = undefined;
  a1.length = 12;

  t.deepEqualTest(a0, a1, 'a literal array and an assigned array', true, true);
  t.end();
});

test('arrays push', function (t) {
  var a0 = [
      undefined,
      null,
      -1,
      0,
      1,
      false,
      true,
      undefined,
      '',
      'abc',
      null,
      undefined
    ],
    a1 = [];

  a1.push(undefined);
  a1.push(null);
  a1.push(-1);
  a1.push(0);
  a1.push(1);
  a1.push(false);
  a1.push(true);
  a1.push(undefined);
  a1.push('');
  a1.push('abc');
  a1.push(null);
  a1.push(undefined);
  a1.length = 12;

  t.deepEqualTest(a0, a1, 'a literal array and a pushed array', true, true);
  t.end();
});

test('null == undefined', function (t) {
  t.deepEqualTest(null, undefined, 'null and undefined', true, false);
  t.deepEqualTest([null], [undefined], '[null] and [undefined]', true, false);

  t.end();
});

// node 14 changed `deepEqual` to make two NaNs loosely equal. TODO, semver-major: change deep-equal in the same way.
var isNode14 = isNode && process.env.ASSERT && semver.satisfies(process.version, '>= 14');
test('NaNs', function (t) {
  t.deepEqualTest(
    NaN,
    NaN,
    'two NaNs',
    isNode14,
    true
  );

  t.deepEqualTest(
    { a: NaN },
    { a: NaN },
    'two equiv objects with a NaN value',
    isNode14,
    true
  );

  t.deepEqualTest(NaN, 1, 'NaN and 1', false, false);

  t.end();
});

test('zeroes', function (t) {
  t.deepEqualTest(0, -0, '0 and -0', true, false);

  t.deepEqualTest({ a: 0 }, { a: -0 }, 'two objects with a same-keyed 0/-0 value', true, false);

  t.end();
});

test('Object.create', { skip: !Object.create }, function (t) {
  var a = { a: 'A' };
  var b = Object.create(a);
  b.b = 'B';
  var c = Object.create(a);
  c.b = 'C';

  t.deepEqualTest(
    b,
    c,
    'two objects with the same [[Prototype]] but a different own property',
    false,
    false
  );

  t.end();
});

test('Object.create(null)', { skip: !Object.create }, function (t) {
  t.deepEqualTest(
    Object.create(null),
    Object.create(null),
    'two empty null objects',
    true,
    true,
    true
  );

  t.deepEqualTest(
    Object.create(null, { a: { value: 'b' } }),
    Object.create(null, { a: { value: 'b' } }),
    'two null objects with the same property pair',
    true,
    true,
    true
  );

  t.end();
});

test('regexes vs dates', function (t) {
  var d = new Date(1387585278000);
  var r = /abc/;

  t.deepEqualTest(d, r, 'Date and RegExp', false, false);

  t.end();
});

test('regexen', function (t) {
  t.deepEqualTest(/abc/, /xyz/, 'two different regexes', false, false);
  t.deepEqualTest(/abc/, /abc/, 'two abc regexes', true, true, false);
  t.deepEqualTest(/xyz/, /xyz/, 'two xyz regexes', true, true, false);

  t.test('fake RegExp', { skip: !hasDunderProto }, function (st) {
    var a = /abc/g;
    var b = tag(Object.create(
      a.__proto__, // eslint-disable-line no-proto
      gOPDs(a)
    ), 'RegExp');

    st.deepEqualTest(a, b, 'regex and fake regex', false, false);

    st.end();
  });

  var a = /abc/gi;
  var b = /abc/gi;
  b.foo = true;
  t.deepEqualTest(
    a,
    b,
    'two identical regexes, one with an extra property',
    false,
    false
  );

  t.end();
});

test('object literals', function (t) {
  t.deepEqualTest(
    { prototype: 2 },
    { prototype: '2' },
    'two loosely equal, strictly inequal prototype properties',
    true,
    false
  );

  t.end();
});

test('arrays and objects', function (t) {
  t.deepEqualTest([], {}, 'empty array and empty object', false, false);
  t.deepEqualTest([], { length: 0 }, 'empty array and empty arraylike object', false, false);
  t.deepEqualTest([1], { 0: 1 }, 'array and similar object', false, false);

  t.end();
});

test('functions', function (t) {
  function f() {}

  t.deepEqualTest(f, f, 'a function and itself', true, true, true);
  t.deepEqualTest([f], [f], 'a function and itself in an array', true, true, true);

  t.deepEqualTest(function () {}, function () {}, 'two distinct functions', false, false, true);
  t.deepEqualTest([function () {}], [function () {}], 'two distinct functions in an array', false, false, true);

  t.deepEqualTest(f, {}, 'function and object', false, false, true);
  t.deepEqualTest([f], [{}], 'function and object in an array', false, false, true);

  t.end();
});

test('Errors', function (t) {
  t.deepEqualTest(new Error('xyz'), new Error('xyz'), 'two errors of the same type with the same message', true, true, false);
  t.deepEqualTest(new Error('xyz'), new TypeError('xyz'), 'two errors of different types with the same message', false, false);
  t.deepEqualTest(new Error('xyz'), new Error('zyx'), 'two errors of the same type with a different message', false, false);

  t.test('errorlike', { skip: !Object.defineProperty }, function (st) {
    var err = new Error('foo');
    // TODO: add `__proto__` when brand check is available
    var errorlike = tag({ message: err.message, stack: err.stack, name: err.name, constructor: err.constructor }, 'Error');
    Object.defineProperty(errorlike, 'message', { enumerable: false });
    Object.defineProperty(errorlike, 'stack', { enumerable: false });
    Object.defineProperty(errorlike, 'name', { enumerable: false });
    Object.defineProperty(errorlike, 'constructor', { enumerable: false });
    st.notOk(errorlike instanceof Error);
    st.ok(err instanceof Error);
    st.deepEqualTest(
      err,
      errorlike,
      'error, and errorlike object',
      false,
      false
    );

    st.end();
  });

  t.deepEqualTest(
    new Error('a'),
    assign(new Error('a'), { code: 10 }),
    'two otherwise equal errors with different own properties',
    false,
    false
  );

  t.test('fake error', { skip: !process.env.ASSERT || !hasDunderProto }, function (st) {
    var a = tag({
      __proto__: null
    }, 'Error');
    var b = new RangeError('abc');
    b.__proto__ = null; // eslint-disable-line no-proto

    st.deepEqualTest(
      a,
      b,
      'null object faking as an Error, RangeError with null proto',
      false,
      false
    );
    st.end();
  });

  t.end();
});

test('object and null', function (t) {
  t.deepEqualTest(
    {},
    null,
    'null and an object',
    false,
    false
  );

  t.end();
});

test('errors', function (t) {

  t.end();
});

test('error = Object', function (t) {
  t.deepEqualTest(
    new Error('a'),
    { message: 'a' },
    false,
    false
  );

  t.end();
});

test('[[Prototypes]]', function (t) {
  function C() {}
  var instance = new C();
  delete instance.constructor;

  t.deepEqualTest({}, instance, 'two identical objects with different [[Prototypes]]', true, false);

  t.test('Dates with different prototypes', { skip: !hasDunderProto }, function (st) {
    var d1 = new Date(0);
    var d2 = new Date(0);

    st.deepEqualTest(d1, d2, 'two dates with the same timestamp', true, true);

    var newProto = {
      __proto__: Date.prototype
    };
    d2.__proto__ = newProto; // eslint-disable-line no-proto
    st.ok(d2 instanceof Date, 'd2 is still a Date instance after tweaking [[Prototype]]');

    st.deepEqualTest(d1, d2, 'two dates with the same timestamp and different [[Prototype]]', true, false);

    st.end();
  });

  t.end();
});

test('toStringTag', { skip: !hasSymbols || !Symbol.toStringTag }, function (t) {
  var o1 = {};
  t.equal(Object.prototype.toString.call(o1), '[object Object]', 'o1: Symbol.toStringTag works');

  var o2 = {};
  t.equal(Object.prototype.toString.call(o2), '[object Object]', 'o2: original Symbol.toStringTag works');

  t.deepEqualTest(o1, o2, 'two normal empty objects', true, true);

  o2[Symbol.toStringTag] = 'jifasnif';
  t.equal(Object.prototype.toString.call(o2), '[object jifasnif]', 'o2: modified Symbol.toStringTag works');

  t.deepEqualTest(o1, o2, 'two normal empty objects with different toStringTags', false, false);

  t.end();
});

test('boxed primitives', function (t) {
  t.deepEqualTest(Object(false), false, 'boxed and primitive `false`', false, false);
  t.deepEqualTest(Object(true), true, 'boxed and primitive `true`', false, false);
  t.deepEqualTest(Object(3), 3, 'boxed and primitive `3`', false, false);
  t.deepEqualTest(Object(NaN), NaN, 'boxed and primitive `NaN`', false, false);
  t.deepEqualTest(Object(''), '', 'boxed and primitive `""`', false, false);
  t.deepEqualTest(Object('str'), 'str', 'boxed and primitive `"str"`', false, false);

  t.test('symbol', { skip: !hasSymbols }, function (st) {
    var s = Symbol('');
    st.deepEqualTest(Object(s), s, 'boxed and primitive `Symbol()`', false, false);
    st.end();
  });

  t.test('bigint', { skip: typeof BigInt !== 'function' }, function (st) {
    var hhgtg = BigInt(42);
    st.deepEqualTest(Object(hhgtg), hhgtg, 'boxed and primitive `BigInt(42)`', false, false);
    st.end();
  });

  t.test('`valueOf` is called for boxed primitives', function (st) {
    var a = Object(5);
    a.valueOf = function () { throw new Error('failed'); };
    var b = Object(5);
    b.valueOf = function () { throw new Error('failed'); };

    st.deepEqualTest(a, b, 'two boxed numbers with a thrower valueOf', false, false);

    st.end();
  });

  t.end();
});

test('getters', { skip: !Object.defineProperty }, function (t) {
  var a = {};
  Object.defineProperty(a, 'a', { enumerable: true, get: function () { return 5; } });
  var b = {};
  Object.defineProperty(b, 'a', { enumerable: true, get: function () { return 6; } });

  t.deepEqualTest(a, b, 'two objects with the same getter but producing different values', false, false);

  t.end();
});

var isBrokenNode = isNode && process.env.ASSERT && semver.satisfies(process.version, '<= 13.3.0');
test('fake arrays: extra keys will be tested', { skip: !hasDunderProto || isBrokenNode }, function (t) {
  var a = tag({
    __proto__: Array.prototype,
    0: 1,
    1: 1,
    2: 'broken',
    length: 2
  }, 'Array');
  if (Object.defineProperty) {
    Object.defineProperty(a, 'length', {
      enumerable: false
    });
  }

  t.deepEqualTest(a, [1, 1], 'fake and real array with same contents and [[Prototype]]', false, false);

  var b = tag(/abc/, 'Array');
  b.__proto__ = Array.prototype; // eslint-disable-line no-proto
  b.length = 3;
  if (Object.defineProperty) {
    Object.defineProperty(b, 'length', {
      enumerable: false
    });
  }
  t.deepEqualTest(b, ['a', 'b', 'c'], 'regex faking as array, and array', false, false);

  t.end();
});

test('circular references', function (t) {
  var b = {};
  b.b = b;

  var c = {};
  c.b = c;

  t.deepEqualTest(
    b,
    c,
    'two self-referencing objects',
    true,
    true
  );

  var d = {};
  d.a = 1;
  d.b = d;

  var e = {};
  e.a = 1;
  e.b = e.a;

  t.deepEqualTest(
    d,
    e,
    'two deeply self-referencing objects',
    false,
    false
  );

  t.end();
});

// io.js v2 is the only version where `console.log(b)` below is catchable
var isNodeWhereBufferBreaks = isNode && semver.satisfies(process.version, '< 3');
var isNode06 = isNode && semver.satisfies(process.version, '<= 0.6'); // segfaults in node 0.6, it seems

test('TypedArrays', { skip: !hasTypedArrays }, function (t) {
  t.test('Buffer faked as Uint8Array', { skip: typeof Buffer !== 'function' || !Object.create || !hasDunderProto || isNode06 }, function (st) {
    var a = safeBuffer('test');
    var b = tag(Object.create(
      a.__proto__, // eslint-disable-line no-proto
      assign(gOPDs(a), {
        length: {
          enumerable: false,
          value: 4
        }
      })
    ), 'Uint8Array');

    st.deepEqualTest(
      a,
      b,
      'Buffer and Uint8Array',
      isNodeWhereBufferBreaks,
      isNodeWhereBufferBreaks
    );

    st.end();
  });

  t.test('one TypedArray faking as another', { skip: !hasDunderProto }, function (st) {
    /* globals Uint8Array, Int8Array */
    var a = new Uint8Array(10);
    var b = tag(new Int8Array(10), 'Uint8Array');
    b.__proto__ = Uint8Array.prototype; // eslint-disable-line no-proto

    st.deepEqualTest(
      a,
      b,
      'Uint8Array, and Int8Array pretending to be a Uint8Array',
      false,
      false
    );

    st.end();
  });

  t.end();
});