test-assert.js

// Copyright Joyent, Inc. and other Node contributors.
//
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// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

'use strict';

const { invalidArgTypeHelper, mustCall } = require('../common');
const assert = require('assert');
const { inspect } = require('util');
const { test } = require('node:test');
const vm = require('vm');

// Disable colored output to prevent color codes from breaking assertion
// message comparisons. This should only be an issue when process.stdout
// is a TTY.
if (process.stdout.isTTY) {
  process.env.NODE_DISABLE_COLORS = '1';
}

const strictEqualMessageStart = 'Expected values to be strictly equal:\n';
const start = 'Expected values to be strictly deep-equal:';
const actExp = '+ actual - expected';

/* eslint-disable no-restricted-syntax */
/* eslint-disable no-restricted-properties */

test('some basics', () => {
  assert.ok(assert.AssertionError.prototype instanceof Error,
            'assert.AssertionError instanceof Error');

  assert.throws(() => assert(false), assert.AssertionError, 'ok(false)');
  assert.throws(() => assert.ok(false), assert.AssertionError, 'ok(false)');
  assert(true);
  assert('test', 'ok(\'test\')');
  assert.ok(true);
  assert.ok('test');
  assert.throws(() => assert.equal(true, false),
                assert.AssertionError, 'equal(true, false)');
  assert.equal(null, null);
  assert.equal(undefined, undefined);
  assert.equal(null, undefined);
  assert.equal(true, true);
  assert.equal(2, '2');
  assert.notEqual(true, false);
  assert.notStrictEqual(2, '2');
});

test('Throw message if the message is instanceof Error', () => {
  let threw = false;
  try {
    assert.ok(false, new Error('ok(false)'));
  } catch (e) {
    threw = true;
    assert.ok(e instanceof Error);
  }
  assert.ok(threw, 'Error: ok(false)');
});

test('Errors created in different contexts are handled as any other custom error', () => {
  const context = vm.createContext();
  const error = vm.runInContext('new SyntaxError("custom error")', context);

  assert.throws(() => assert(false, error), {
    message: 'custom error',
    name: 'SyntaxError'
  });
});

test('assert.throws()', () => {
  assert.throws(() => assert.notEqual(true, true),
                assert.AssertionError, 'notEqual(true, true)');

  assert.throws(() => assert.strictEqual(2, '2'),
                assert.AssertionError, 'strictEqual(2, \'2\')');

  assert.throws(() => assert.strictEqual(null, undefined),
                assert.AssertionError, 'strictEqual(null, undefined)');

  assert.throws(
    () => assert.notStrictEqual(2, 2),
    {
      message: 'Expected "actual" to be strictly unequal to: 2',
      name: 'AssertionError'
    }
  );

  assert.throws(
    () => assert.notStrictEqual('a '.repeat(30), 'a '.repeat(30)),
    {
      message: 'Expected "actual" to be strictly unequal to:\n\n' +
              `'${'a '.repeat(30)}'`,
      name: 'AssertionError'
    }
  );

  assert.throws(
    () => assert.notEqual(1, 1),
    {
      message: '1 != 1',
      operator: '!='
    }
  );

  // Testing the throwing.
  function thrower(errorConstructor) {
    throw new errorConstructor({});
  }

  // The basic calls work.
  assert.throws(() => thrower(assert.AssertionError), assert.AssertionError, 'message');
  assert.throws(() => thrower(assert.AssertionError), assert.AssertionError);
  assert.throws(() => thrower(assert.AssertionError));

  // If not passing an error, catch all.
  assert.throws(() => thrower(TypeError));

  // When passing a type, only catch errors of the appropriate type.
  assert.throws(
    () => assert.throws(() => thrower(TypeError), assert.AssertionError),
    {
      generatedMessage: true,
      actual: new TypeError({}),
      expected: assert.AssertionError,
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      operator: 'throws',
      message: 'The error is expected to be an instance of "AssertionError". ' +
              'Received "TypeError"\n\nError message:\n\n[object Object]'
    }
  );

  // doesNotThrow should pass through all errors.
  {
    let threw = false;
    try {
      assert.doesNotThrow(() => thrower(TypeError), assert.AssertionError);
    } catch (e) {
      threw = true;
      assert.ok(e instanceof TypeError);
    }
    assert(threw, 'assert.doesNotThrow with an explicit error is eating extra errors');
  }

  // Key difference is that throwing our correct error makes an assertion error.
  {
    let threw = false;
    try {
      assert.doesNotThrow(() => thrower(TypeError), TypeError);
    } catch (e) {
      threw = true;
      assert.ok(e instanceof assert.AssertionError);
      assert.ok(!e.stack.includes('at Function.doesNotThrow'));
    }
    assert.ok(threw, 'assert.doesNotThrow is not catching type matching errors');
  }

  assert.throws(
    () => assert.doesNotThrow(() => thrower(Error), 'user message'),
    {
      name: 'AssertionError',
      code: 'ERR_ASSERTION',
      operator: 'doesNotThrow',
      message: 'Got unwanted exception: user message\n' +
              'Actual message: "[object Object]"'
    }
  );

  assert.throws(
    () => assert.doesNotThrow(() => thrower(Error)),
    {
      code: 'ERR_ASSERTION',
      message: 'Got unwanted exception.\nActual message: "[object Object]"'
    }
  );

  assert.throws(
    () => assert.doesNotThrow(() => thrower(Error), /\[[a-z]{6}\s[A-z]{6}\]/g, 'user message'),
    {
      name: 'AssertionError',
      code: 'ERR_ASSERTION',
      operator: 'doesNotThrow',
      message: 'Got unwanted exception: user message\n' +
              'Actual message: "[object Object]"'
    }
  );

  // Make sure that validating using constructor really works.
  {
    let threw = false;
    try {
      assert.throws(
        () => {
          throw ({}); // eslint-disable-line no-throw-literal
        },
        Array
      );
    } catch {
      threw = true;
    }
    assert.ok(threw, 'wrong constructor validation');
  }

  // Use a RegExp to validate the error message.
  {
    assert.throws(() => thrower(TypeError), /\[object Object\]/);

    const symbol = Symbol('foo');
    assert.throws(() => {
      throw symbol;
    }, /foo/);

    assert.throws(() => {
      assert.throws(() => {
        throw symbol;
      }, /abc/);
    }, {
      message: 'The input did not match the regular expression /abc/. ' +
              "Input:\n\n'Symbol(foo)'\n",
      code: 'ERR_ASSERTION',
      operator: 'throws',
      actual: symbol,
      expected: /abc/
    });
  }

  // Use a fn to validate the error object.
  assert.throws(() => thrower(TypeError), (err) => {
    if ((err instanceof TypeError) && /\[object Object\]/.test(err)) {
      return true;
    }
  });

  // https://github.com/nodejs/node/issues/3188
  {
    let actual;
    assert.throws(
      () => {
        const ES6Error = class extends Error {};
        const AnotherErrorType = class extends Error {};

        assert.throws(() => {
          actual = new AnotherErrorType('foo');
          throw actual;
        }, ES6Error);
      },
      (err) => {
        assert.strictEqual(
          err.message,
          'The error is expected to be an instance of "ES6Error". ' +
            'Received "AnotherErrorType"\n\nError message:\n\nfoo'
        );
        assert.strictEqual(err.actual, actual);
        return true;
      }
    );
  }

  assert.throws(
    () => assert.strictEqual(new Error('foo'), new Error('foobar')),
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'Expected "actual" to be reference-equal to "expected":\n' +
        '+ actual - expected\n' +
        '\n' +
        '+ [Error: foo]\n' +
        '- [Error: foobar]\n'
    }
  );
});

test('Check messages from assert.throws()', () => {
  const noop = () => {};
  assert.throws(
    () => { assert.throws((noop)); },
    {
      code: 'ERR_ASSERTION',
      message: 'Missing expected exception.',
      operator: 'throws',
      actual: undefined,
      expected: undefined
    });

  assert.throws(
    () => { assert.throws(noop, TypeError); },
    {
      code: 'ERR_ASSERTION',
      message: 'Missing expected exception (TypeError).',
      actual: undefined,
      expected: TypeError
    });

  assert.throws(
    () => { assert.throws(noop, 'fhqwhgads'); },
    {
      code: 'ERR_ASSERTION',
      message: 'Missing expected exception: fhqwhgads',
      actual: undefined,
      expected: undefined
    });

  assert.throws(
    () => { assert.throws(noop, TypeError, 'fhqwhgads'); },
    {
      code: 'ERR_ASSERTION',
      message: 'Missing expected exception (TypeError): fhqwhgads',
      actual: undefined,
      expected: TypeError
    });

  let threw = false;
  try {
    assert.throws(noop);
  } catch (e) {
    threw = true;
    assert.ok(e instanceof assert.AssertionError);
    assert.ok(!e.stack.includes('at Function.throws'));
  }
  assert.ok(threw);
});

test('Test assertion messages', () => {
  const circular = { y: 1 };
  circular.x = circular;

  function testAssertionMessage(actual, expected, msg) {
    assert.throws(
      () => assert.strictEqual(actual, ''),
      {
        generatedMessage: true,
        message: msg || `Expected values to be strictly equal:\n\n${expected} !== ''\n`
      }
    );
  }

  function testLongAssertionMessage(actual, expected) {
    testAssertionMessage(actual, expected, 'Expected values to be strictly equal:\n' +
          '+ actual - expected\n' +
          '\n' +
          `+ ${expected}\n` +
          "- ''\n");
  }

  function testShortAssertionMessage(actual, expected) {
    testAssertionMessage(actual, expected, strictEqualMessageStart + `\n${inspect(actual)} !== ''\n`);
  }

  testShortAssertionMessage(null, 'null');
  testShortAssertionMessage(true, 'true');
  testShortAssertionMessage(false, 'false');
  testShortAssertionMessage(100, '100');
  testShortAssertionMessage(NaN, 'NaN');
  testShortAssertionMessage(Infinity, 'Infinity');
  testShortAssertionMessage('a', '\'a\'');
  testShortAssertionMessage('foo', '\'foo\'');
  testShortAssertionMessage(0, '0');
  testShortAssertionMessage(Symbol(), 'Symbol()');
  testShortAssertionMessage(undefined, 'undefined');
  testShortAssertionMessage(-Infinity, '-Infinity');
  testShortAssertionMessage([], '[]');
  testShortAssertionMessage({}, '{}');
  testAssertionMessage(/a/, '/a/');
  testAssertionMessage(/abc/gim, '/abc/gim');
  testLongAssertionMessage(function f() {}, '[Function: f]');
  testLongAssertionMessage(function() {}, '[Function (anonymous)]');

  assert.throws(
    () => assert.strictEqual([1, 2, 3], ''),
    {
      message: 'Expected values to be strictly equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '+ [\n' +
        '+   1,\n' +
        '+   2,\n' +
        '+   3\n' +
        '+ ]\n' +
        "- ''\n",
      generatedMessage: true
    }
  );

  assert.throws(
    () => assert.strictEqual(circular, ''),
    {
      message: 'Expected values to be strictly equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '+ <ref *1> {\n' +
        '+   x: [Circular *1],\n' +
        '+   y: 1\n' +
        '+ }\n' +
        "- ''\n",
      generatedMessage: true
    }
  );

  assert.throws(
    () => assert.strictEqual({ a: undefined, b: null }, ''),
    {
      message: 'Expected values to be strictly equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '+ {\n' +
        '+   a: undefined,\n' +
        '+   b: null\n' +
        '+ }\n' +
        "- ''\n",
      generatedMessage: true
    }
  );

  assert.throws(
    () => assert.strictEqual({ a: NaN, b: Infinity, c: -Infinity }, ''),
    {
      message: 'Expected values to be strictly equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '+ {\n' +
        '+   a: NaN,\n' +
        '+   b: Infinity,\n' +
        '+   c: -Infinity\n' +
        '+ }\n' +
        "- ''\n",
      generatedMessage: true
    }
  );

  // https://github.com/nodejs/node-v0.x-archive/issues/5292
  assert.throws(
    () => assert.strictEqual(1, 2),
    {
      message: 'Expected values to be strictly equal:\n\n1 !== 2\n',
      generatedMessage: true
    }
  );

  assert.throws(
    () => assert.strictEqual(1, 2, 'oh no'),
    {
      message: 'oh no\n\n1 !== 2\n',
      generatedMessage: false
    }
  );
});

test('Custom errors', () => {
  let threw = false;
  const rangeError = new RangeError('my range');

  // Verify custom errors.
  try {
    assert.strictEqual(1, 2, rangeError);
  } catch (e) {
    assert.strictEqual(e, rangeError);
    threw = true;
    assert.ok(e instanceof RangeError, 'Incorrect error type thrown');
  }
  assert.ok(threw);
  threw = false;

  // Verify AssertionError is the result from doesNotThrow with custom Error.
  try {
    assert.doesNotThrow(() => {
      throw new TypeError('wrong type');
    }, TypeError, rangeError);
  } catch (e) {
    threw = true;
    assert.ok(e.message.includes(rangeError.message));
    assert.ok(e instanceof assert.AssertionError);
    assert.ok(!e.stack.includes('doesNotThrow'), e);
  }
  assert.ok(threw);
});

test('Verify that throws() and doesNotThrow() throw on non-functions', () => {
  [
    [assert.throws, 'string'],
    [assert.doesNotThrow, 'string'],
    [assert.throws, 1],
    [assert.doesNotThrow, 1],
    [assert.throws, true],
    [assert.doesNotThrow, true],
    [assert.throws, false],
    [assert.doesNotThrow, false],
    [assert.throws, []],
    [assert.doesNotThrow, []],
    [assert.throws, {}],
    [assert.doesNotThrow, {}],
    [assert.throws, /foo/],
    [assert.doesNotThrow, /foo/],
    [assert.throws, null],
    [assert.doesNotThrow, null],
    [assert.throws, undefined],
    [assert.doesNotThrow, undefined],
  ].forEach(([method, fn]) => {
    assert.throws(
      () => method(fn),
      {
        code: 'ERR_INVALID_ARG_TYPE',
        name: 'TypeError',
        message: 'The "fn" argument must be of type function.' +
                 invalidArgTypeHelper(fn)
      }
    );
  });
});

test('https://github.com/nodejs/node/issues/3275', () => {
  // eslint-disable-next-line no-throw-literal
  assert.throws(() => { throw 'error'; }, (err) => err === 'error');
  assert.throws(() => { throw new Error(); }, (err) => err instanceof Error);
});

test('Long values should be truncated for display', () => {
  assert.throws(() => {
    assert.strictEqual('A'.repeat(1000), '');
  }, (err) => {
    assert.strictEqual(err.code, 'ERR_ASSERTION');
    assert.strictEqual(err.message,
                       `${strictEqualMessageStart}+ actual - expected\n\n` +
                      `+ '${'A'.repeat(1000)}'\n- ''\n`);
    assert.strictEqual(err.actual.length, 1000);
    assert.ok(inspect(err).includes(`actual: '${'A'.repeat(488)}...'`));
    return true;
  });
});

test('Output that extends beyond 10 lines should also be truncated for display', () => {
  const multilineString = 'fhqwhgads\n'.repeat(15);
  assert.throws(() => {
    assert.strictEqual(multilineString, '');
  }, (err) => {
    assert.strictEqual(err.code, 'ERR_ASSERTION');
    assert.strictEqual(err.message.split('\n').length, 20);
    assert.strictEqual(err.actual.split('\n').length, 16);
    assert.ok(inspect(err).includes(
      "actual: 'fhqwhgads\\n' +\n" +
      "    'fhqwhgads\\n' +\n".repeat(9) +
      "    '...'"));
    return true;
  });
});

test('Bad args to AssertionError constructor should throw TypeError.', () => {
  const args = [1, true, false, '', null, Infinity, Symbol('test'), undefined];
  for (const input of args) {
    assert.throws(
      () => new assert.AssertionError(input),
      {
        code: 'ERR_INVALID_ARG_TYPE',
        name: 'TypeError',
        message: 'The "options" argument must be of type object.' +
                 invalidArgTypeHelper(input)
      });
  }
});

test('NaN is handled correctly', () => {
  assert.equal(NaN, NaN);
  assert.throws(
    () => assert.notEqual(NaN, NaN),
    assert.AssertionError
  );
});

test('Test strict assert', () => {
  // eslint-disable-next-line node-core/must-call-assert
  const { strict } = require('assert');

  strict.throws(() => strict.equal(1, true), strict.AssertionError);
  strict.notEqual(0, false);
  strict.throws(() => strict.deepEqual(1, true), strict.AssertionError);
  strict.notDeepEqual(0, false);
  strict.equal(strict.strict, strict.strict.strict);
  strict.equal(strict.equal, strict.strictEqual);
  strict.equal(strict.deepEqual, strict.deepStrictEqual);
  strict.equal(strict.notEqual, strict.notStrictEqual);
  strict.equal(strict.notDeepEqual, strict.notDeepStrictEqual);
  strict.equal(Object.keys(strict).length, Object.keys(assert).length);
  strict(7);
  strict.throws(
    () => strict(...[]),
    {
      message: 'No value argument passed to `assert.ok()`',
      name: 'AssertionError',
      generatedMessage: true
    }
  );
  strict.throws(
    mustCall(() => assert()),
    {
      message: 'No value argument passed to `assert.ok()`',
      name: 'AssertionError'
    }
  );

  // Test setting the limit to zero and that assert.strict works properly.
  const tmpLimit = Error.stackTraceLimit;
  Error.stackTraceLimit = 0;
  strict.throws(
    () => {
      strict.ok(
        typeof 123 === 'string'
      );
    },
    {
      code: 'ERR_ASSERTION',
      constructor: strict.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
               'strict.ok(\n'
    }
  );
  Error.stackTraceLimit = tmpLimit;

  // Test error diffs.
  let message = 'Expected values to be strictly deep-equal:\n' +
    '+ actual - expected\n' +
    '\n' +
    '  [\n' +
    '    [\n' +
    '      [\n' +
    '        1,\n' +
    '        2,\n' +
    '+       3\n' +
    "-       '3'\n" +
    '      ]\n' +
    '    ],\n' +
    '    4,\n' +
    '    5\n' +
    '  ]\n';
  strict.throws(
    () => strict.deepEqual([[[1, 2, 3]], 4, 5], [[[1, 2, '3']], 4, 5]),
    { message });

  message = 'Expected values to be strictly deep-equal:\n' +
    '+ actual - expected\n' +
    '... Skipped lines\n' +
    '\n' +
    '  [\n' +
    '    1,\n' +
    '    1,\n' +
    '    1,\n' +
    '    0,\n' +
    '...\n' +
    '    1,\n' +
    '+   1\n' +
    '  ]\n';
  strict.throws(
    () => strict.deepEqual(
      [1, 1, 1, 0, 1, 1, 1, 1],
      [1, 1, 1, 0, 1, 1, 1]),
    { message });

  message = 'Expected values to be strictly deep-equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '  [\n' +
        '    1,\n' +
        '    2,\n' +
        '    3,\n' +
        '    4,\n' +
        '    5,\n' +
        '+   6,\n' +
        '-   9,\n' +
        '    7\n' +
        '  ]\n';

  assert.throws(
    () => assert.deepStrictEqual([1, 2, 3, 4, 5, 6, 7], [1, 2, 3, 4, 5, 9, 7]),
    { message }
  );

  message = 'Expected values to be strictly deep-equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        '  [\n' +
        '    1,\n' +
        '    2,\n' +
        '    3,\n' +
        '    4,\n' +
        '    5,\n' +
        '    6,\n' +
        '+   7,\n' +
        '-   9,\n' +
        '    8\n' +
        '  ]\n';

  assert.throws(
    () => assert.deepStrictEqual([1, 2, 3, 4, 5, 6, 7, 8], [1, 2, 3, 4, 5, 6, 9, 8]),
    { message }
  );

  message = 'Expected values to be strictly deep-equal:\n' +
        '+ actual - expected\n' +
        '... Skipped lines\n' +
        '\n' +
        '  [\n' +
        '    1,\n' +
        '    2,\n' +
        '    3,\n' +
        '    4,\n' +
        '...\n' +
        '    7,\n' +
        '+   8,\n' +
        '-   0,\n' +
        '    9\n' +
        '  ]\n';

  assert.throws(
    () => assert.deepStrictEqual([1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 0, 9]),
    { message }
  );

  message = 'Expected values to be strictly deep-equal:\n' +
    '+ actual - expected\n' +
    '\n' +
    '  [\n' +
    '    1,\n' +
    '+   2,\n' +
    '    1,\n' +
    '    1,\n' +
    '-   1,\n' +
    '    0,\n' +
    '    1,\n' +
    '+   1\n' +
    '  ]\n';
  strict.throws(
    () => strict.deepEqual(
      [1, 2, 1, 1, 0, 1, 1],
      [1, 1, 1, 1, 0, 1]),
    { message });

  message = [
    start,
    actExp,
    '',
    '+ [',
    '+   1,',
    '+   2,',
    '+   1',
    '+ ]',
    '- undefined\n',
  ].join('\n');
  strict.throws(
    () => strict.deepEqual([1, 2, 1], undefined),
    { message });

  message = [
    start,
    actExp,
    '',
    '  [',
    '+   1,',
    '    2,',
    '    1',
    '  ]\n',
  ].join('\n');
  strict.throws(
    () => strict.deepEqual([1, 2, 1], [2, 1]),
    { message });

  message = 'Expected values to be strictly deep-equal:\n' +
  '+ actual - expected\n' +
      '\n' +
      '  [\n' +
      '+   1,\n'.repeat(10) +
      '+   3\n' +
      '-   2,\n'.repeat(11) +
      '-   4,\n' +
      '-   4,\n' +
      '-   4\n' +
      '  ]\n';
  strict.throws(
    () => strict.deepEqual([1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3], [2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4]),
    { message });

  const obj1 = {};
  const obj2 = { loop: 'forever' };
  obj2[inspect.custom] = () => '{}';
  // No infinite loop and no custom inspect.
  strict.throws(() => strict.deepEqual(obj1, obj2), {
    message: `${start}\n` +
    `${actExp}\n` +
    '\n' +
    '+ {}\n' +
    '- {\n' +
    '-   Symbol(nodejs.util.inspect.custom): [Function (anonymous)],\n' +
    "-   loop: 'forever'\n" +
    '- }\n'
  });

  // notDeepEqual tests
  strict.throws(
    () => strict.notDeepEqual([1], [1]),
    {
      message: 'Expected "actual" not to be strictly deep-equal to:\n\n' +
               '[\n  1\n]\n'
    }
  );

  message = 'Expected "actual" not to be strictly deep-equal to:' +
            `\n\n[${'\n  1,'.repeat(45)}\n...\n`;
  const data = Array(51).fill(1);
  strict.throws(
    () => strict.notDeepEqual(data, data),
    { message });

});

test('Additional asserts', () => {
  assert.throws(
    () => assert.ok(null),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      generatedMessage: true,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert.ok(null)\n'
    }
  );
  assert.throws(
    () => {
      // This test case checks if `try` left brace without a line break
      // before the assertion causes any wrong assertion message.
      // Therefore, don't reformat the following code.
      // Refs: https://github.com/nodejs/node/issues/30872
      try { assert.ok(0);   // eslint-disable-line no-useless-catch, @stylistic/js/brace-style
      } catch (err) {
        throw err;
      }
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      generatedMessage: true,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert.ok(0)\n'
    }
  );
  assert.throws(
    () => {
      try {
        throw new Error();
      // This test case checks if `catch` left brace without a line break
      // before the assertion causes any wrong assertion message.
      // Therefore, don't reformat the following code.
      // Refs: https://github.com/nodejs/node/issues/30872
      } catch (err) { assert.ok(0); }     // eslint-disable-line no-unused-vars
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      generatedMessage: true,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert.ok(0)\n'
    }
  );
  assert.throws(
    () => {
      // This test case checks if `function` left brace without a line break
      // before the assertion causes any wrong assertion message.
      // Therefore, don't reformat the following code.
      // Refs: https://github.com/nodejs/node/issues/30872
      function test() { assert.ok(0);     // eslint-disable-line @stylistic/js/brace-style
      }
      test();
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      generatedMessage: true,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert.ok(0)\n'
    }
  );
  assert.throws(
    () => assert(typeof 123n === 'string'),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      generatedMessage: true,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              "assert(typeof 123n === 'string')\n"
    }
  );

  assert.throws(
    () => assert(false, Symbol('foo')),
    {
      code: 'ERR_INVALID_ARG_TYPE',
      constructor: TypeError,
      message: /"message" argument.+Symbol\(foo\)/
    }
  );

  assert.throws(
    () => {
      assert.strictEqual((() => 'string')(), 123 instanceof
            Buffer);
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'Expected values to be strictly equal:\n\n\'string\' !== false\n'
    }
  );

  assert.throws(
    () => {
      assert.strictEqual((() => 'string')(), 123 instanceof
            Buffer);
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'Expected values to be strictly equal:\n\n\'string\' !== false\n'
    }
  );

  /* eslint-disable @stylistic/js/indent */
  assert.throws(() => {
  assert.strictEqual((
    () => 'string')(), 123 instanceof
  Buffer);
  }, {
    code: 'ERR_ASSERTION',
    constructor: assert.AssertionError,
    message: 'Expected values to be strictly equal:\n\n\'string\' !== false\n'
    }
  );
  /* eslint-enable @stylistic/js/indent */

  assert.throws(
    () => {
      assert(true); assert(null, undefined);
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert(null, undefined)\n'
    }
  );

  assert.throws(
    () => {
      assert
      .ok(null, undefined);
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'ok(null, undefined)\n'
    }
  );

  assert.throws(
    // eslint-disable-next-line dot-notation, @stylistic/js/quotes
    () => assert['ok']["apply"](null, [0]),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert[\'ok\']["apply"](null, [0])\n'
    }
  );

  assert.throws(
    () => {
      const wrapper = (fn, value) => fn(value);
      wrapper(assert, false);
    },
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  fn(value)\n'
    }
  );

  assert.throws(
    () => assert.ok.call(null, 0),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  ' +
              'assert.ok.call(null, 0)\n',
      generatedMessage: true
    }
  );

  assert.throws(
    () => assert.ok.call(null, 0, 'test'),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'test',
      generatedMessage: false
    }
  );

  // Works in eval. Source code in eval can be shown.
  assert.throws(
    () => new Function('assert', 'assert(1 === 2);')(assert),
    {
      code: 'ERR_ASSERTION',
      constructor: assert.AssertionError,
      message: 'The expression evaluated to a falsy value:\n\n  assert(1 === 2)\n'
    }
  );
  assert.throws(
    () => eval('console.log("FOO");\nassert.ok(1 === 2);'),
    {
      code: 'ERR_ASSERTION',
      message: 'The expression evaluated to a falsy value:\n\n  assert.ok(1 === 2)\n'
    }
  );

  assert.throws(
    () => assert.throws(() => {}, 'Error message', 'message'),
    {
      code: 'ERR_INVALID_ARG_TYPE',
      name: 'TypeError',
      message: 'The "error" argument must be of type function or ' +
              'an instance of Error, RegExp, or Object. Received type string ' +
              "('Error message')"
    }
  );

  const inputs = [1, false, Symbol()];
  for (const input of inputs) {
    assert.throws(
      () => assert.throws(() => {}, input),
      {
        code: 'ERR_INVALID_ARG_TYPE',
        message: 'The "error" argument must be of type function or ' +
                'an instance of Error, RegExp, or Object.' +
                invalidArgTypeHelper(input)
      }
    );
  }
});

test('Throws accepts objects', () => {
  assert.throws(() => {
    // eslint-disable-next-line no-constant-binary-expression
    assert.ok((() => Boolean('
' === false))());
  }, {
    message: 'The expression evaluated to a falsy value:\n\n' +
             "  assert.ok((() => Boolean('\\u0001' === false))())\n"
  });

  const errFn = () => {
    const err = new TypeError('Wrong value');
    err.code = 404;
    throw err;
  };
  const errObj = {
    name: 'TypeError',
    message: 'Wrong value'
  };
  assert.throws(errFn, errObj);

  errObj.code = 404;
  assert.throws(errFn, errObj);

  // Fail in case a expected property is undefined and not existent on the
  // error.
  errObj.foo = undefined;
  assert.throws(
    () => assert.throws(errFn, errObj),
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: `${start}\n${actExp}\n\n` +
               '  Comparison {\n' +
               '    code: 404,\n' +
               '-   foo: undefined,\n' +
               "    message: 'Wrong value',\n" +
               "    name: 'TypeError'\n" +
               '  }\n'
    }
  );

  // Show multiple wrong properties at the same time.
  errObj.code = '404';
  assert.throws(
    () => assert.throws(errFn, errObj),
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: `${start}\n${actExp}\n\n` +
               '  Comparison {\n' +
               '+   code: 404,\n' +
               "-   code: '404',\n" +
               '-   foo: undefined,\n' +
               "    message: 'Wrong value',\n" +
               "    name: 'TypeError'\n" +
               '  }\n'
    }
  );

  assert.throws(
    () => assert.throws(() => { throw new Error(); }, { foo: 'bar' }, 'foobar'),
    {
      constructor: assert.AssertionError,
      code: 'ERR_ASSERTION',
      message: 'foobar'
    }
  );

  assert.throws(
    () => assert.doesNotThrow(() => { throw new Error(); }, { foo: 'bar' }),
    {
      name: 'TypeError',
      code: 'ERR_INVALID_ARG_TYPE',
      message: 'The "expected" argument must be of type function or an ' +
               'instance of RegExp. Received an instance of Object'
    }
  );

  assert.throws(() => { throw new Error('e'); }, new Error('e'));
  assert.throws(
    () => assert.throws(() => { throw new TypeError('e'); }, new Error('e')),
    {
      name: 'AssertionError',
      code: 'ERR_ASSERTION',
      message: `${start}\n${actExp}\n\n` +
               '  Comparison {\n' +
               "    message: 'e',\n" +
               "+   name: 'TypeError'\n" +
               "-   name: 'Error'\n" +
               '  }\n'
    }
  );
  assert.throws(
    () => assert.throws(() => { throw new Error('foo'); }, new Error('')),
    {
      name: 'AssertionError',
      code: 'ERR_ASSERTION',
      generatedMessage: true,
      message: `${start}\n${actExp}\n\n` +
               '  Comparison {\n' +
               "+   message: 'foo',\n" +
               "-   message: '',\n" +
               "    name: 'Error'\n" +
               '  }\n'
    }
  );

  // eslint-disable-next-line no-throw-literal
  assert.throws(() => { throw undefined; }, /undefined/);
  assert.throws(
    // eslint-disable-next-line no-throw-literal
    () => assert.doesNotThrow(() => { throw undefined; }),
    {
      name: 'AssertionError',
      code: 'ERR_ASSERTION',
      message: 'Got unwanted exception.\nActual message: "undefined"'
    }
  );
});

test('Additional assert', () => {
  assert.throws(
    () => assert.throws(() => { throw new Error(); }, {}),
    {
      message: "The argument 'error' may not be an empty object. Received {}",
      code: 'ERR_INVALID_ARG_VALUE'
    }
  );

  assert.throws(
    () => assert.throws(
      // eslint-disable-next-line no-throw-literal
      () => { throw 'foo'; },
      'foo'
    ),
    {
      code: 'ERR_AMBIGUOUS_ARGUMENT',
      message: 'The "error/message" argument is ambiguous. ' +
              'The error "foo" is identical to the message.'
    }
  );

  assert.throws(
    () => assert.throws(
      () => { throw new TypeError('foo'); },
      'foo'
    ),
    {
      code: 'ERR_AMBIGUOUS_ARGUMENT',
      message: 'The "error/message" argument is ambiguous. ' +
              'The error message "foo" is identical to the message.'
    }
  );

  // Should not throw.
  assert.throws(() => { throw null; }, 'foo');  // eslint-disable-line no-throw-literal

  assert.throws(
    () => assert.strictEqual([], []),
    {
      message: 'Values have same structure but are not reference-equal:\n\n[]\n'
    }
  );

  {
    const args = (function() { return arguments; })('a');
    assert.throws(
      () => assert.strictEqual(args, { 0: 'a' }),
      {
        message: 'Expected "actual" to be reference-equal to "expected":\n' +
                '+ actual - expected\n\n' +
                "+ [Arguments] {\n- {\n    '0': 'a'\n  }\n"
      }
    );
  }

  assert.throws(
    () => { throw new TypeError('foobar'); },
    {
      message: /foo/,
      name: /^TypeError$/
    }
  );

  assert.throws(
    () => assert.throws(
      () => { throw new TypeError('foobar'); },
      {
        message: /fooa/,
        name: /^TypeError$/
      }
    ),
    {
      message: `${start}\n${actExp}\n\n` +
              '  Comparison {\n' +
              "+   message: 'foobar',\n" +
              '-   message: /fooa/,\n' +
              "    name: 'TypeError'\n" +
              '  }\n'
    }
  );

  {
    let actual = null;
    const expected = { message: 'foo' };
    assert.throws(
      () => assert.throws(
        () => { throw actual; },
        expected
      ),
      {
        operator: 'throws',
        actual,
        expected,
        generatedMessage: true,
        message: `${start}\n${actExp}\n\n` +
                '+ null\n' +
                '- {\n' +
                "-   message: 'foo'\n" +
                '- }\n'
      }
    );

    actual = 'foobar';
    const message = 'message';
    assert.throws(
      () => assert.throws(
        () => { throw actual; },
        { message: 'foobar' },
        message
      ),
      {
        actual,
        message: "message\n+ actual - expected\n\n+ 'foobar'\n- {\n-   message: 'foobar'\n- }\n",
        operator: 'throws',
        generatedMessage: false
      }
    );
  }

  // Indicate where the strings diverge.
  assert.throws(
    () => assert.strictEqual('test test', 'test foobar'),
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'Expected values to be strictly equal:\n' +
        '+ actual - expected\n' +
        '\n' +
        "+ 'test test'\n" +
        "- 'test foobar'\n" +
        '        ^\n',
    }
  );

  // Check for reference-equal objects in `notStrictEqual()`
  assert.throws(
    () => {
      const obj = {};
      assert.notStrictEqual(obj, obj);
    },
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'Expected "actual" not to be reference-equal to "expected": {}'
    }
  );

  assert.throws(
    () => {
      const obj = { a: true };
      assert.notStrictEqual(obj, obj);
    },
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'Expected "actual" not to be reference-equal to "expected":\n\n' +
              '{\n  a: true\n}\n'
    }
  );

  assert.throws(
    () => {
      assert.deepStrictEqual({ a: true }, { a: false }, 'custom message');
    },
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'custom message\n+ actual - expected\n\n  {\n+   a: true\n-   a: false\n  }\n'
    }
  );

  assert.throws(
    () => {
      assert.partialDeepStrictEqual({ a: true }, { a: false }, 'custom message');
    },
    {
      code: 'ERR_ASSERTION',
      name: 'AssertionError',
      message: 'custom message\n+ actual - expected\n\n  {\n+   a: true\n-   a: false\n  }\n'
    }
  );

  {
    let threw = false;
    try {
      assert.deepStrictEqual(Array(100).fill(1), 'foobar');
    } catch (err) {
      threw = true;
      assert.match(inspect(err), /actual: \[Array],\n {2}expected: 'foobar',/);
    }
    assert(threw);
  }

  assert.throws(
    () => assert.equal(1),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.deepEqual(/a/),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.notEqual(null),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.notDeepEqual('test'),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.strictEqual({}),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.deepStrictEqual(Symbol()),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.notStrictEqual(5n),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.notDeepStrictEqual(undefined),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.strictEqual(),
    { code: 'ERR_MISSING_ARGS' }
  );

  assert.throws(
    () => assert.deepStrictEqual(),
    { code: 'ERR_MISSING_ARGS' }
  );

  // Verify that `stackStartFunction` works as alternative to `stackStartFn`.
  {
    (function hidden() {
      const err = new assert.AssertionError({
        actual: 'foo',
        operator: 'strictEqual',
        stackStartFunction: hidden
      });
      const err2 = new assert.AssertionError({
        actual: 'foo',
        operator: 'strictEqual',
        stackStartFn: hidden
      });
      assert(!err.stack.includes('hidden'));
      assert(!err2.stack.includes('hidden'));
    })();
  }

  assert.throws(
    () => assert.throws(() => { throw Symbol('foo'); }, RangeError),
    {
      message: 'The error is expected to be an instance of "RangeError". ' +
              'Received "Symbol(foo)"'
    }
  );

  assert.throws(
    // eslint-disable-next-line no-throw-literal
    () => assert.throws(() => { throw [1, 2]; }, RangeError),
    {
      message: 'The error is expected to be an instance of "RangeError". ' +
              'Received "[Array]"'
    }
  );

  {
    const err = new TypeError('foo');
    const validate = (() => () => ({ a: true, b: [ 1, 2, 3 ] }))();
    assert.throws(
      () => assert.throws(() => { throw err; }, validate),
      {
        message: 'The validation function is expected to ' +
                `return "true". Received ${inspect(validate())}\n\nCaught ` +
                `error:\n\n${err}`,
        code: 'ERR_ASSERTION',
        actual: err,
        expected: validate,
        name: 'AssertionError',
        operator: 'throws',
      }
    );
  }

  assert.throws(
    () => {
      const script = new vm.Script('new RangeError("foobar");');
      const context = vm.createContext();
      const err = script.runInContext(context);
      assert.throws(() => { throw err; }, RangeError);
    },
    {
      message: 'The error is expected to be an instance of "RangeError". ' +
              'Received an error with identical name but a different ' +
              'prototype.\n\nError message:\n\nfoobar'
    }
  );

  // Multiple assert.match() tests.
  {
    assert.throws(
      () => assert.match(/abc/, 'string'),
      {
        code: 'ERR_INVALID_ARG_TYPE',
        message: 'The "regexp" argument must be an instance of RegExp. ' +
                "Received type string ('string')"
      }
    );
    assert.throws(
      () => assert.match('string', /abc/),
      {
        actual: 'string',
        expected: /abc/,
        operator: 'match',
        message: 'The input did not match the regular expression /abc/. ' +
                "Input:\n\n'string'\n",
        generatedMessage: true
      }
    );
    assert.throws(
      () => assert.match('string', /abc/, 'foobar'),
      {
        actual: 'string',
        expected: /abc/,
        operator: 'match',
        message: 'foobar',
        generatedMessage: false
      }
    );
    const errorMessage = new RangeError('foobar');
    assert.throws(
      () => assert.match('string', /abc/, errorMessage),
      errorMessage
    );
    assert.throws(
      () => assert.match({ abc: 123 }, /abc/),
      {
        actual: { abc: 123 },
        expected: /abc/,
        operator: 'match',
        message: 'The "string" argument must be of type string. ' +
                'Received type object ({ abc: 123 })',
        generatedMessage: true
      }
    );
    assert.match('I will pass', /pass$/);
  }

  // Multiple assert.doesNotMatch() tests.
  {
    assert.throws(
      () => assert.doesNotMatch(/abc/, 'string'),
      {
        code: 'ERR_INVALID_ARG_TYPE',
        message: 'The "regexp" argument must be an instance of RegExp. ' +
                "Received type string ('string')"
      }
    );
    assert.throws(
      () => assert.doesNotMatch('string', /string/),
      {
        actual: 'string',
        expected: /string/,
        operator: 'doesNotMatch',
        message: 'The input was expected to not match the regular expression ' +
                "/string/. Input:\n\n'string'\n",
        generatedMessage: true
      }
    );
    assert.throws(
      () => assert.doesNotMatch('string', /string/, 'foobar'),
      {
        actual: 'string',
        expected: /string/,
        operator: 'doesNotMatch',
        message: 'foobar',
        generatedMessage: false
      }
    );
    const errorMessage = new RangeError('foobar');
    assert.throws(
      () => assert.doesNotMatch('string', /string/, errorMessage),
      errorMessage
    );
    assert.throws(
      () => assert.doesNotMatch({ abc: 123 }, /abc/),
      {
        actual: { abc: 123 },
        expected: /abc/,
        operator: 'doesNotMatch',
        message: 'The "string" argument must be of type string. ' +
                'Received type object ({ abc: 123 })',
        generatedMessage: true
      }
    );
    assert.doesNotMatch('I will pass', /different$/);
  }
});

test('assert/strict exists', () => {
  // eslint-disable-next-line node-core/must-call-assert
  assert.strictEqual(require('assert/strict'), assert.strict);
});

test('assert.strict.partialDeepEqual is an alias for partialDeepStrictEqual', () => {
  assert.strictEqual(
    assert.strict.partialDeepEqual,
    assert.strict.partialDeepStrictEqual
  );
});

test('Printf-like format strings as error message', () => {
  assert.throws(
    () => assert.equal(1, 2, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.strictEqual(1, 2, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.notEqual(1, 1, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.notStrictEqual(1, 1, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.deepEqual(1, 2, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.notDeepEqual(1, 1, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.deepStrictEqual(1, 2, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.notDeepStrictEqual(1, 1, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.partialDeepStrictEqual(1, 2, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.match('foo', /bar/, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );

  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, 'The answer to all questions is %i', 42),
    /The answer to all questions is 42/
  );
});

test('Functions as error message', () => {
  function errorMessage(actual, expected) {
    return `Nice message including ${actual} and ${expected}`;
  }
  assert.throws(
    () => assert.equal(1, 2, errorMessage),
    { message: 'Nice message including 1 and 2' }
  );

  assert.throws(
    () => assert.strictEqual(1, 2, errorMessage),
    // TODO(BridgeAR): Align input arguments with generated message for all
    // methods.
    // TODO(BridgeAR): Check how to handle this for custom messages. Do
    // we need this? Should it be skipped for methods like these?
    { message: 'Nice message including 1 and 2\n\n1 !== 2\n' }
  );

  assert.throws(
    () => assert.notEqual(1, 1, errorMessage),
    { message: 'Nice message including 1 and 1' }
  );

  assert.throws(
    () => assert.notStrictEqual(1, 1, errorMessage),
    { message: 'Nice message including 1 and 1' }
  );

  assert.throws(
    () => assert.deepEqual(1, 2, errorMessage),
    { message: 'Nice message including 1 and 2' }
  );

  assert.throws(
    () => assert.notDeepEqual(1, 1, errorMessage),
    { message: 'Nice message including 1 and 1' }
  );

  assert.throws(
    () => assert.deepStrictEqual(1, 2, errorMessage),
    { message: 'Nice message including 1 and 2\n\n1 !== 2\n' }
  );

  assert.throws(
    () => assert.notDeepStrictEqual(1, 1, errorMessage),
    { message: 'Nice message including 1 and 1' }
  );

  assert.throws(
    () => assert.partialDeepStrictEqual(1, 2, errorMessage),
    { message: 'Nice message including 1 and 2\n\n1 !== 2\n' }
  );

  assert.throws(
    () => assert.match('foo', /bar/, errorMessage),
    { message: 'Nice message including foo and /bar/' }
  );

  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, errorMessage),
    { message: 'Nice message including foo and /foo/' }
  );
});

test('Ambiguous error messages fail', () => {
  function errorMessage(actual, expected) {
    return `Nice message including ${actual} and ${expected}`;
  }

  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, errorMessage, 'foobar'),
    {
      code: 'ERR_AMBIGUOUS_ARGUMENT',
      message: /errorMessage/
    }
  );

  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, new Error('baz'), 'foobar'),
    {
      code: 'ERR_AMBIGUOUS_ARGUMENT',
      message: /baz/
    }
  );
});

test('Faulty message functions', () => {
  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, (a, b) => 123),
    {
      code: 'ERR_ASSERTION',
      message: "'foo' doesNotMatch /foo/"
    }
  );

  assert.throws(
    () => assert.match('foo', /123/, (a, b) => { new Error('baz'); }),
    {
      code: 'ERR_ASSERTION',
      message: "'foo' match /123/"
    }
  );
});

test('Functions as error message', () => {
  function errorMessage(actual, expected) {
    return `Nice message including ${actual} and ${expected}`;
  }

  assert.throws(
    () => assert.equal('foo', 'bar', errorMessage),
    {
      code: 'ERR_ASSERTION',
      message: /Nice message including foo and bar/
    }
  );

  assert.throws(
    () => assert.doesNotMatch('foo', /foo/, errorMessage),
    {
      code: 'ERR_ASSERTION',
      message: /Nice message including foo and \/foo\//
    }
  );
});

/* eslint-enable no-restricted-syntax */
/* eslint-enable no-restricted-properties */