diff --git a/tests/spec/s-json.js b/tests/spec/s-json.js
new file mode 100644
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--- /dev/null
+++ b/tests/spec/s-json.js
@@ -0,0 +1,544 @@
+/* global describe, it, expect,beforeEach */
+
+/* Ported from JSON 3 Unit Test Suite | https://bestiejs.github.io/json3 */
+describe('JSON', function () {
+  var parse = function (text, reviver) {
+    return function () {
+      return JSON.parse(text, reviver);
+    };
+  };
+  var stringify = function (value, replacer, space) {
+    return function () {
+      return JSON.stringify(value, replacer, space);
+    };
+  };
+  // Ensures that `JSON.parse` throws an exception when parsing the given
+  // `source` string.
+  beforeEach(function () {
+    this.addMatchers({
+      toError: function (expected, message) {
+        var pass = false;
+        var exception;
+        if (typeof this.actual !== 'function') {
+          throw new Error('Actual is not a function');
+        }
+        if (typeof expected !== 'function' || !(expected() instanceof Error)) {
+          throw new Error('Expected is not an Error constructor');
+        }
+        var msg = '';
+        if (typeof message === 'string') {
+          msg = message;
+        }
+        try {
+          this.actual();
+        } catch (e) {
+          exception = e;
+        }
+        if (exception) {
+          pass = exception instanceof expected;
+        }
+        if (!pass) {
+          this.message = function () {
+            return ['Expected' + (message ? ' "' + message + '"' : message) + ' to throw an instance of ' + expected() + ', but ' + (exception ? 'threw ' + exception : 'did not throw')];
+          };
+        }
+        return pass;
+      }
+    });
+  });
+  // Tests
+  // -----
+  it('`parse`: Empty Source Strings', function () {
+    expect(parse('')).toError(SyntaxError, 'Empty JSON source string');
+    expect(parse('\n\n\r\n')).toError(SyntaxError, 'Source string containing only line terminators');
+    expect(parse(' ')).toError(SyntaxError, 'Source string containing a single space character');
+    expect(parse(' ')).toError(SyntaxError, 'Source string containing multiple space characters');
+  });
+  it('`parse`: Whitespace', function () {
+    // The only valid JSON whitespace characters are tabs, spaces, and line
+    // terminators. All other Unicode category `Z` (`Zs`, `Zl`, and `Zp`)
+    // characters are invalid (note that the `Zs` category includes the
+    // space character).
+    var characters = [
+        '{\u00a0}',
+        '{\u1680}',
+        '{\u180e}',
+        '{\u2000}',
+        '{\u2001}',
+        '{\u2002}',
+        '{\u2003}',
+        '{\u2004}',
+        '{\u2005}',
+        '{\u2006}',
+        '{\u2007}',
+        '{\u2008}',
+        '{\u2009}',
+        '{\u200a}',
+        '{\u202f}',
+        '{\u205f}',
+        '{\u3000}',
+        '{\u2028}',
+        '{\u2029}'
+    ];
+    characters.forEach(function (value) {
+      expect(parse(value)).toError(SyntaxError, 'Source string containing an invalid Unicode whitespace character');
+    });
+    expect(parse('{\u000b}')).toError(SyntaxError, 'Source string containing a vertical tab');
+    expect(parse('{\u000c}')).toError(SyntaxError, 'Source string containing a form feed');
+    expect(parse('{\ufeff}')).toError(SyntaxError, 'Source string containing a byte-order mark');
+    expect(JSON.parse('{\r\n}')).toEqual({}, 'Source string containing a CRLF line ending');
+    expect(JSON.parse('{\n\n\r\n}')).toEqual({}, 'Source string containing multiple line terminators');
+    expect(JSON.parse('{\t}')).toEqual({}, 'Source string containing a tab character');
+    expect(JSON.parse('{ }')).toEqual({}, 'Source string containing a space character');
+  });
+  it('`parse`: Octal Values', function () {
+    // `08` and `018` are invalid octal values.
+    var octal = ['00', '01', '02', '03', '04', '05', '06', '07', '010', '011', '08', '018'];
+    octal.forEach(function (value) {
+      expect(parse(value)).toError(SyntaxError, 'Octal literal');
+      expect(parse('-' + value)).toError(SyntaxError, 'Negative octal literal');
+      expect(parse('"\\' + value + '"')).toError(SyntaxError, 'Octal escape sequence in a string');
+      expect(parse('"\\x' + value + '"')).toError(SyntaxError, 'Hex escape sequence in a string');
+    });
+  });
+  it('`parse`: Numeric Literals', function () {
+    expect(JSON.parse('100')).toBe(100, 'Integer');
+    expect(JSON.parse('-100')).toBe(-100, 'Negative integer');
+    expect(JSON.parse('10.5')).toBe(10.5, 'Float');
+    expect(JSON.parse('-3.141')).toBe(-3.141, 'Negative float');
+    expect(JSON.parse('0.625')).toBe(0.625, 'Decimal');
+    expect(JSON.parse('-0.03125')).toBe(-0.03125, 'Negative decimal');
+    expect(JSON.parse('1e3')).toBe(1000, 'Exponential');
+    expect(JSON.parse('1e+2')).toBe(100, 'Positive exponential');
+    expect(JSON.parse('-1e-2')).toBe(-0.01, 'Negative exponential');
+    expect(JSON.parse('0.03125e+5')).toBe(3125, 'Decimalized exponential');
+    expect(JSON.parse('1E2')).toBe(100, 'Case-insensitive exponential delimiter');
+    expect(parse('+1')).toError(SyntaxError, 'Leading `+`');
+    expect(parse('1.')).toError(SyntaxError, 'Trailing decimal point');
+    expect(parse('.1')).toError(SyntaxError, 'Leading decimal point');
+    expect(parse('1e')).toError(SyntaxError, 'Missing exponent');
+    expect(parse('1e-')).toError(SyntaxError, 'Missing signed exponent');
+    expect(parse('--1')).toError(SyntaxError, 'Leading `--`');
+    expect(parse('1-+')).toError(SyntaxError, 'Trailing `-+`');
+    expect(parse('0xaf')).toError(SyntaxError, 'Hex literal');
+    // The native `JSON.parse` implementation in IE 9 allows this syntax, but
+    // the feature tests should detect the broken implementation.
+    expect(parse('- 5')).toError(SyntaxError, 'Invalid negative sign');
+  });
+  it('`parse`: String Literals', function () {
+    var expected = 48;
+    var controlCharacters = [
+      '\u0001',
+      '\u0002',
+      '\u0003',
+      '\u0004',
+      '\u0005',
+      '\u0006',
+      '\u0007',
+      '\b',
+      '\t',
+      '\n',
+      '\u000b',
+      '\f',
+      '\r',
+      '\u000e',
+      '\u000f',
+      '\u0010',
+      '\u0011',
+      '\u0012',
+      '\u0013',
+      '\u0014',
+      '\u0015',
+      '\u0016',
+      '\u0017',
+      '\u0018',
+      '\u0019',
+      '\u001a',
+      '\u001b',
+      '\u001c',
+      '\u001d',
+      '\u001e',
+      '\u001f'
+    ];
+    // Opera 7 discards null characters in strings.
+    if ('\0'.length) {
+      expected += 1;
+      controlCharacters.push('\u0000');
+    }
+    expect(JSON.parse('"value"')).toBe('value', 'Double-quoted string literal');
+    expect(JSON.parse('""')).toBe('', 'Empty string literal');
+    expect(JSON.parse('"\\u2028"')).toBe('\u2028', 'String containing an escaped Unicode line separator');
+    expect(JSON.parse('"\\u2029"')).toBe('\u2029', 'String containing an escaped Unicode paragraph separator');
+    // ExtendScript doesn't handle surrogate pairs correctly; attempting to
+    // parse `"\ud834\udf06"` will throw an uncatchable error (issue #29).
+    expect(JSON.parse('"\ud834\udf06"')).toBe('\ud834\udf06', 'String containing an unescaped Unicode surrogate pair');
+    expect(JSON.parse('"\\u0001"')).toBe('\u0001', 'String containing an escaped ASCII control character');
+    expect(JSON.parse('"\\b"')).toBe('\b', 'String containing an escaped backspace');
+    expect(JSON.parse('"\\f"')).toBe('\f', 'String containing an escaped form feed');
+    expect(JSON.parse('"\\n"')).toBe('\n', 'String containing an escaped line feed');
+    expect(JSON.parse('"\\r"')).toBe('\r', 'String containing an escaped carriage return');
+    expect(JSON.parse('"\\t"')).toBe('\t', 'String containing an escaped tab');
+    expect(JSON.parse('"hello\\/world"')).toBe('hello/world', 'String containing an escaped solidus');
+    expect(JSON.parse('"hello\\\\world"')).toBe('hello\\world', 'String containing an escaped reverse solidus');
+    expect(JSON.parse('"hello\\"world"')).toBe('hello"world', 'String containing an escaped double-quote character');
+    expect(parse('\'hello\'')).toError(SyntaxError, 'Single-quoted string literal');
+    expect(parse('"\\x61"')).toError(SyntaxError, 'String containing a hex escape sequence');
+    expect(parse('"hello \r\n world"')).toError(SyntaxError, 'String containing an unescaped CRLF line ending');
+    controlCharacters.forEach(function (value) {
+      expect(parse('"' + value + '"')).toError(SyntaxError, 'String containing an unescaped ASCII control character');
+    });
+  });
+  it('`parse`: Array Literals', function () {
+    expect(parse('[1, 2, 3,]')).toError(SyntaxError, 'Trailing comma in array literal');
+    expect(JSON.parse('[1, 2, [3, [4, 5]], 6, [true, false], [null], [[]]]')).toEqual([1, 2, [3, [4, 5]], 6, [true, false], [null], [[]]], 'Nested arrays');
+    expect(JSON.parse('[{}]')).toEqual([{}], 'Array containing empty object literal');
+    var expected = [
+      100,
+      true,
+      false,
+      null,
+      {
+        a: ['hello'],
+        b: ['world']
+      },
+      [0.01]
+    ];
+    expect(JSON.parse('[1e2, true, false, null, {"a": ["hello"], "b": ["world"]}, [1e-2]]')).toEqual(expected, 'Mixed array');
+  });
+  it('`parse`: Object Literals', function () {
+    expect(JSON.parse('{"hello": "world"}')).toEqual({ hello: 'world' }, 'Object literal containing one member');
+    expect(JSON.parse('{"hello": "world", "foo": ["bar", true], "fox": {"quick": true, "purple": false}}')).toEqual({
+      hello: 'world',
+      foo: ['bar', true],
+      fox: {
+        quick: true,
+        purple: false
+      }
+    }, 'Object literal containing multiple members');
+    expect(parse('{key: 1}')).toError(SyntaxError, 'Unquoted identifier used as a property name');
+    expect(parse('{false: 1}')).toError(SyntaxError, '`false` used as a property name');
+    expect(parse('{true: 1}')).toError(SyntaxError, '`true` used as a property name');
+    expect(parse('{null: 1}')).toError(SyntaxError, '`null` used as a property name');
+    expect(parse('{\'key\': 1}')).toError(SyntaxError, 'Single-quoted string used as a property name');
+    expect(parse('{1: 2, 3: 4}')).toError(SyntaxError, 'Number used as a property name');
+    expect(parse('{"hello": "world", "foo": "bar",}')).toError(SyntaxError, 'Trailing comma in object literal');
+  });
+  // JavaScript expressions should never be evaluated, as JSON 3 does not use
+  // `eval`.
+  it('`parse`: Invalid Expressions', function () {
+    var expressions = [
+      '1 + 1',
+      '1 * 2',
+      'var value = 123;',
+      '{});value = 123;({}',
+      'call()',
+      '1, 2, 3, "value"'
+    ];
+    expressions.forEach(function (expression) {
+      expect(parse(expression)).toError(SyntaxError, 'Source string containing a JavaScript expression');
+    });
+  });
+  it('`stringify` and `parse`: Optional Arguments', function () {
+    expect(JSON.parse('{"a": 1, "b": "10000"}', function (key, value) {
+      return typeof value === 'string' ? parseInt(value, 2) : value;
+    })).toEqual({
+      a: 1,
+      b: 16
+    }, 'Callback function provided');
+    expect(JSON.stringify({
+      foo: 123,
+      bar: 456
+    }, ['bar'], 2)).toBe('{\n  "bar": 456\n}', 'Object; optional `filter` and `whitespace` arguments');
+    // Test adapted from the Opera JSON test suite via Ken Snyder.
+    // See http://testsuites.opera.com/JSON/correctness/scripts/045.js
+    // The regular expression is necessary because the ExtendScript engine
+    // only approximates pi to 14 decimal places (ES 3 and ES 5 approximate
+    // pi to 15 places).
+    expect(/^\{"PI":3\.\d{14,15}\}$/.test(JSON.stringify(Math, ['PI'])), 'List of non-enumerable property names specified as the `filter` argument').toBe(true);
+    expect(JSON.parse('[1, 2, 3]', function (key, value) {
+      if (typeof value === 'object' && value) {
+        return value;
+      }
+    }).length, 'Issue #10: `walk` should not use `splice` when removing an array element').toBe(3);
+  });
+  it('`stringify`', function () {
+    var expected = 30;
+    // Special values.
+    expect(JSON.stringify(null)).toBe('null', '`null` is represented literally');
+    expect(JSON.stringify(1 / 0)).toBe('null', '`Infinity` is serialized as `null`');
+    expect(JSON.stringify(0 / 0)).toBe('null', '`NaN` is serialized as `null`');
+    expect(JSON.stringify(-1 / 0)).toBe('null', '`-Infinity` is serialized as `null`');
+    expect(JSON.stringify(true)).toBe('true', 'Boolean primitives are represented literally');
+    expect(JSON.stringify(Object(false))).toBe('false', 'Boolean objects are represented literally');
+    expect(JSON.stringify(Object('\\"How\bquickly\tdaft\njumping\fzebras\rvex"'))).toBe('"\\\\\\"How\\bquickly\\tdaft\\njumping\\fzebras\\rvex\\""', 'All control characters in strings are escaped');
+    expect(JSON.stringify([Object(false), Object(1), Object('Kit')])).toBe('[false,1,"Kit"]', 'Arrays are serialized recursively');
+    expect(JSON.stringify([void 0])).toBe('[null]', '`[undefined]` is serialized as `[null]`');
+    // Property enumeration is implementation-dependent.
+    var value = {
+      jdalton: ['John-David', 29],
+      kitcambridge: ['Kit', 18],
+      mathias: ['Mathias', 23]
+    };
+    var jsonStr = '{"jdalton":["John-David",29],"kitcambridge":["Kit",18],"mathias":["Mathias",23]}';
+    expect(JSON.stringify(value)).toBe(jsonStr, 'Objects are serialized recursively');
+    expect(JSON.parse(jsonStr)).toEqual(value, 'Objects are deserialized recursively');
+    expect(JSON.parse(JSON.stringify(value))).toEqual(value, 'Objects are serialized/deserialized recursively');
+    // Complex cyclic structures.
+    value = {
+      foo: {
+        b: {
+          foo: {
+            c: {
+              foo: null
+            }
+          }
+        }
+      }
+    };
+    expect(JSON.stringify(value)).toBe('{"foo":{"b":{"foo":{"c":{"foo":null}}}}}', 'Nested objects containing identically-named properties should serialize correctly');
+    var S = [], N = {};
+    S.push(N, N);
+    expect(JSON.stringify(S)).toBe('[{},{}]', 'Objects containing duplicate references should not throw a `TypeError`');
+    value.foo.b.foo.c.foo = value;
+    expect(stringify(value)).toError(TypeError, 'Objects containing complex circular references should throw a `TypeError`');
+    // Sparse arrays.
+    value = [];
+    value[5] = 1;
+    expect(JSON.stringify(value)).toBe('[null,null,null,null,null,1]', 'Sparse arrays should serialize correctly');
+    // Dates.
+    expect(JSON.stringify(new Date(Date.UTC(1994, 6, 3)))).toBe('"1994-07-03T00:00:00.000Z"', 'Dates should be serialized according to the simplified date time string format');
+    expect(JSON.stringify(new Date(Date.UTC(1993, 5, 2, 2, 10, 28, 224)))).toBe('"1993-06-02T02:10:28.224Z"', 'The date time string should conform to the format outlined in the spec');
+    expect(JSON.stringify(new Date(-8.64e15))).toBe('"-271821-04-20T00:00:00.000Z"', 'The minimum valid date value should serialize correctly');
+    expect(JSON.stringify(new Date(8.64e15))).toBe('"+275760-09-13T00:00:00.000Z"', 'The maximum valid date value should serialize correctly');
+    expect(JSON.stringify(new Date(Date.UTC(10000, 0, 1)))).toBe('"+010000-01-01T00:00:00.000Z"', 'https://bugs.ecmascript.org/show_bug.cgi?id=119');
+    value = new Date();
+    value.toJSON = function () {
+      return 'date';
+    };
+    expect(JSON.stringify(value)).toBe('"date"');
+    // Tests based on research by @Yaffle. See kriskowal/es5-shim#111.
+    expect(JSON.stringify(new Date(-1))).toBe('"1969-12-31T23:59:59.999Z"', 'Millisecond values < 1000 should be serialized correctly');
+    expect(JSON.stringify(new Date(-621987552e5))).toBe('"-000001-01-01T00:00:00.000Z"', 'Years prior to 0 should be serialized as extended years');
+    expect(JSON.stringify(new Date(2534023008e5))).toBe('"+010000-01-01T00:00:00.000Z"', 'Years after 9999 should be serialized as extended years');
+    expect(JSON.stringify(new Date(-3509827334573292))).toBe('"-109252-01-01T10:37:06.708Z"', 'Issue #4: Opera > 9.64 should correctly serialize a date with a year of `-109252`');
+    // Opera 7 normalizes dates with invalid time values to represent the
+    // current date.
+    value = new Date('Kit');
+    if (!isFinite(value)) {
+      expected += 1;
+      expect(JSON.stringify(value)).toBe('null', 'Invalid dates should serialize as `null`');
+    }
+    // Additional arguments.
+    expect(JSON.stringify([1, 2, 3, [4, 5]], null, '  ')).toBe('[\n  1,\n  2,\n  3,\n  [\n    4,\n    5\n  ]\n]', 'Nested arrays; optional `whitespace` argument');
+    expect(JSON.stringify([], null, '  ')).toBe('[]', 'Empty array; optional string `whitespace` argument');
+    expect(JSON.stringify({}, null, 2)).toBe('{}', 'Empty object; optional numeric `whitespace` argument');
+    expect(JSON.stringify([1], null, 2)).toBe('[\n  1\n]', 'Single-element array; optional numeric `whitespace` argument');
+    expect(JSON.stringify({
+      foo: 123
+    }, null, '  ')).toBe('{\n  "foo": 123\n}', 'Single-member object; optional string `whitespace` argument');
+    expect(JSON.stringify({
+      foo: {
+        bar: [123]
+      }
+    }, null, 2)).toBe('{\n  "foo": {\n    "bar": [\n      123\n    ]\n  }\n}', 'Nested objects; optional numeric `whitespace` argument');
+  });
+
+  /*
+   * The following tests are adapted from the ECMAScript 5 Conformance Suite.
+   * Copyright 2009, Microsoft Corporation. Distributed under the New BSD License.
+   *
+   * Redistribution and use in source and binary forms, with or without
+   * modification, are permitted provided that the following conditions are met:
+   *
+   *   - Redistributions of source code must retain the above copyright notice,
+   *     this list of conditions and the following disclaimer.
+   *   - Redistributions in binary form must reproduce the above copyright notice,
+   *     this list of conditions and the following disclaimer in the documentation
+   *     and/or other materials provided with the distribution.
+   *   - Neither the name of Microsoft nor the names of its contributors may be
+   *     used to endorse or promote products derived from this software without
+   *     specific prior written permission.
+   *
+   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+   * POSSIBILITY OF SUCH DAMAGE.
+  */
+  it('ECMAScript 5 Conformance', function () {
+    var value = {
+      a1: {
+        b1: [1, 2, 3, 4],
+        b2: {
+          c1: 1,
+          c2: 2
+        }
+      },
+      a2: 'a2'
+    };
+    // Section 15.12.1.1: The JSON Grammar.
+    // ------------------------------------
+    // Tests 15.12.1.1-0-1 thru 15.12.1.1-0-8.
+    expect(parse('12\t\r\n 34')).toError(SyntaxError, 'Valid whitespace characters may not separate two discrete tokens');
+    expect(parse('\u000b1234')).toError(SyntaxError, 'The vertical tab is not a valid whitespace character');
+    expect(parse('\u000c1234')).toError(SyntaxError, 'The form feed is not a valid whitespace character');
+    expect(parse('\u00a01234')).toError(SyntaxError, 'The non-breaking space is not a valid whitespace character');
+    expect(parse('\u200b1234')).toError(SyntaxError, 'The zero-width space is not a valid whitespace character');
+    expect(parse('\ufeff1234')).toError(SyntaxError, 'The byte order mark (zero-width non-breaking space) is not a valid whitespace character');
+    expect(parse('\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u30001234')).toError(SyntaxError, 'Other Unicode category `Z` characters are not valid whitespace characters');
+    expect(parse('\u2028\u20291234')).toError(SyntaxError, 'The line (U+2028) and paragraph (U+2029) separators are not valid whitespace characters');
+    // Test 15.12.1.1-0-9.
+    expect(JSON.parse('\t\r \n{\t\r \n"property"\t\r \n:\t\r \n{\t\r \n}\t\r \n,\t\r \n"prop2"\t\r \n:\t\r \n[\t\r \ntrue\t\r \n,\t\r \nnull\t\r \n,123.456\t\r \n]\t\r \n}\t\r \n')).toEqual({
+      property: {},
+      prop2: [true, null, 123.456]
+    }, 'Valid whitespace characters may precede and follow all tokens');
+    // Tests 15.12.1.1-g1-1 thru 15.12.1.1-g1-4.
+    expect(JSON.parse('\t1234')).toBe(1234, 'Leading tab characters should be ignored');
+    expect(parse('12\t34')).toError(SyntaxError, 'A tab character may not separate two disparate tokens');
+    expect(JSON.parse('\r1234')).toBe(1234, 'Leading carriage returns should be ignored');
+    expect(parse('12\r34')).toError(SyntaxError, 'A carriage return may not separate two disparate tokens');
+    expect(JSON.parse('\n1234')).toBe(1234, 'Leading line feeds should be ignored');
+    expect(parse('12\n34')).toError(SyntaxError, 'A line feed may not separate two disparate tokens');
+    expect(JSON.parse(' 1234')).toBe(1234, 'Leading space characters should be ignored');
+    expect(parse('12 34')).toError(SyntaxError, 'A space character may not separate two disparate tokens');
+    // Tests 15.12.1.1-g2-1 thru 15.12.1.1-g2-5.
+    expect(JSON.parse('"abc"')).toBe('abc', 'Strings must be enclosed in double quotes');
+    expect(parse('\'abc\'')).toError(SyntaxError, 'Single-quoted strings are not permitted');
+    // Note: the original test 15.12.1.1-g2-3 (`"\u0022abc\u0022"`) is incorrect,
+    // as the JavaScript interpreter will always convert `\u0022` to `"`.
+    expect(parse('\\u0022abc\\u0022')).toError(SyntaxError, 'Unicode-escaped double quote delimiters are not permitted');
+    expect(parse('"abc\'')).toError(SyntaxError, 'Strings must terminate with a double quote character');
+    expect(JSON.parse('""')).toBe('', 'Strings may be empty');
+    // Tests 15.12.1.1-g4-1 thru 15.12.1.1-g4-4.
+    expect(parse('"\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007"')).toError(SyntaxError, 'Unescaped control characters in the range [U+0000, U+0007] are not permitted within strings');
+    expect(parse('"\u0008\u0009\u000a\u000b\u000c\u000d\u000e\u000f"')).toError(SyntaxError, 'Unescaped control characters in the range [U+0008, U+000F] are not permitted within strings');
+    expect(parse('"\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017"')).toError(SyntaxError, 'Unescaped control characters in the range [U+0010, U+0017] are not permitted within strings');
+    expect(parse('"\u0018\u0019\u001a\u001b\u001c\u001d\u001e\u001f"')).toError(SyntaxError, 'Unescaped control characters in the range [U+0018, U+001F] are not permitted within strings');
+    // Tests 15.12.1.1-g5-1 thru 15.12.1.1-g5-3.
+    expect(JSON.parse('"\\u0058"')).toBe('X', 'Unicode escape sequences are permitted within strings');
+    expect(parse('"\\u005"')).toError(SyntaxError, 'Unicode escape sequences may not comprise fewer than four hexdigits');
+    expect(parse('"\\u0X50"')).toError(SyntaxError, 'Unicode escape sequences may not contain non-hex characters');
+    // Tests 15.12.1.1-g6-1 thru 15.12.1.1-g6-7.
+    expect(JSON.parse('"\\/"')).toBe('/', 'Escaped solidus');
+    expect(JSON.parse('"\\\\"')).toBe('\\', 'Escaped reverse solidus');
+    expect(JSON.parse('"\\b"')).toBe('\b', 'Escaped backspace');
+    expect(JSON.parse('"\\f"')).toBe('\f', 'Escaped form feed');
+    expect(JSON.parse('"\\n"')).toBe('\n', 'Escaped line feed');
+    expect(JSON.parse('"\\r"')).toBe('\r', 'Escaped carriage return');
+    expect(JSON.parse('"\\t"')).toBe('\t', 'Escaped tab');
+
+    // Section 15.12.3: `JSON.stringify()`.
+    // ------------------------------------
+    // Test 15.12.3-11-1 thru 5.12.3-11-15.
+    expect(JSON.stringify(void 0)).toBe(void 0, '`JSON.stringify(undefined)` should return `undefined`');
+    expect(JSON.stringify(void 0, function () {
+      return 'replacement';
+    })).toBe('"replacement"', 'The `JSON.stringify` callback function can be called on a top-level `undefined` value');
+    expect(JSON.stringify('a string')).toBe('"a string"', '`JSON.stringify` should serialize top-level string primitives');
+    expect(JSON.stringify(123)).toBe('123', '`JSON.stringify` should serialize top-level number primitives');
+    expect(JSON.stringify(true)).toBe('true', '`JSON.stringify` should serialize top-level Boolean primitives');
+    expect(JSON.stringify(null)).toBe('null', '`JSON.stringify` should serialize top-level `null` values');
+    expect(JSON.stringify(Object(42))).toBe('42', '`JSON.stringify` should serialize top-level number objects');
+    expect(JSON.stringify(Object('wrapped'))).toBe('"wrapped"', '`JSON.stringify` should serialize top-level string objects');
+    expect(JSON.stringify(Object(false))).toBe('false', '`JSON.stringify` should serialize top-level Boolean objects');
+    expect(JSON.stringify(42, function () {
+      return void 0;
+    })).toBe(void 0, 'The `JSON.stringify` callback function may return `undefined` when called on a top-level number primitive');
+    expect(JSON.stringify({
+      prop: 1
+    }, function () {
+      return void 0;
+    })).toBe(void 0, 'The `JSON.stringify` callback function may return `undefined` when called on a top-level object');
+    expect(JSON.stringify(42, function (key, value) {
+      return value === 42 ? [4, 2] : value;
+    })).toBe('[4,2]', 'The `JSON.stringify` callback function may return an array when called on a top-level number primitive');
+    expect(JSON.stringify(42, function (key, value) {
+      return value === 42 ? {
+        forty: 2
+      } : value;
+    })).toBe('{"forty":2}', 'The `JSON.stringify` callback function may return an object literal when called on a top-level number primitive');
+    expect(JSON.stringify(function () {})).toBe(void 0, '`JSON.stringify` should return `undefined` when called on a top-level function');
+    expect(JSON.stringify(function () {}, function () {
+      return 99;
+    })).toBe('99', 'The `JSON.stringify` callback function may return a number primitive when called on a top-level function');
+    // Test 15.12.3-4-1.
+    expect(JSON.stringify([42], {})).toBe('[42]', '`JSON.stringify` should ignore `filter` arguments that are not functions or arrays');
+    // Test 15.12.3-5-a-i-1 and 15.12.3-5-b-i-1.
+    expect(JSON.stringify(value, null, 5)).toBe(JSON.stringify(value, null, Object(5)), 'Optional `width` argument: Number object and primitive width values should produce identical results');
+    expect(JSON.stringify(value, null, 'xxx')).toBe(JSON.stringify(value, null, Object('xxx')), 'Optional `width` argument: String object and primitive width values should produce identical results');
+    // Test 15.12.3-6-a-1 and 15.12.3-6-a-2.
+    expect(JSON.stringify(value, null, 100)).toBe(JSON.stringify(value, null, 10), 'Optional `width` argument: The maximum numeric width value should be 10');
+    expect(JSON.stringify(value, null, 5.99999)).toBe(JSON.stringify(value, null, 5), 'Optional `width` argument: Numeric values should be converted to integers');
+    // Test 15.12.3-6-b-1 and 15.12.3-6-b-4.
+    expect(JSON.stringify(value, null, 0.999999)).toBe(JSON.stringify(value), 'Optional `width` argument: Numeric width values between 0 and 1 should be ignored');
+    expect(JSON.stringify(value, null, 0)).toBe(JSON.stringify(value), 'Optional `width` argument: Zero should be ignored');
+    expect(JSON.stringify(value, null, -5)).toBe(JSON.stringify(value), 'Optional `width` argument: Negative numeric values should be ignored');
+    expect(JSON.stringify(value, null, 5)).toBe(JSON.stringify(value, null, '     '), 'Optional `width` argument: Numeric width values in the range [1, 10] should produce identical results to that of string values containing `width` spaces');
+    // Test 15.12.3-7-a-1.
+    expect(JSON.stringify(value, null, '0123456789xxxxxxxxx')).toBe(JSON.stringify(value, null, '0123456789'), 'Optional `width` argument: String width values longer than 10 characters should be truncated');
+    // Test 15.12.3-8-a-1 thru 15.12.3-8-a-5.
+    expect(JSON.stringify(value, null, '')).toBe(JSON.stringify(value), 'Empty string `width` arguments should be ignored');
+    expect(JSON.stringify(value, null, true)).toBe(JSON.stringify(value), 'Boolean primitive `width` arguments should be ignored');
+    expect(JSON.stringify(value, null, null)).toBe(JSON.stringify(value), '`null` `width` arguments should be ignored');
+    expect(JSON.stringify(value, null, Object(false))).toBe(JSON.stringify(value), 'Boolean object `width` arguments should be ignored');
+    expect(JSON.stringify(value, null, value)).toBe(JSON.stringify(value), 'Object literal `width` arguments should be ignored');
+    // Test 15.12.3@2-2-b-i-1.
+    expect(JSON.stringify([
+      {
+        prop: 42,
+        toJSON: function () {
+          return 'fortytwo objects';
+        }
+      }
+    ])).toBe('["fortytwo objects"]', 'An object literal with a custom `toJSON` method nested within an array may return a string primitive for serialization');
+    // Test 15.12.3@2-2-b-i-2.
+    expect(JSON.stringify([
+      {
+        prop: 42,
+        toJSON: function () {
+          return Object(42);
+        }
+      }
+    ])).toBe('[42]', 'An object literal with a custom `toJSON` method nested within an array may return a number object for serialization');
+    // Test 15.12.3@2-2-b-i-3.
+    expect(JSON.stringify([
+      {
+        prop: 42,
+        toJSON: function () {
+          return Object(true);
+        }
+      }
+    ])).toBe('[true]', 'An object literal with a custom `toJSON` method nested within an array may return a Boolean object for serialization');
+    // Test 15.12.3@2-3-a-1.
+    expect(JSON.stringify([42], function (key, value) {
+      return value === 42 ? Object('fortytwo') : value;
+    })).toBe('["fortytwo"]', 'The `JSON.stringify` callback function may return a string object when called on an array');
+    // Test 15.12.3@2-3-a-2.
+    expect(JSON.stringify([42], function (key, value) {
+      return value === 42 ? Object(84) : value;
+    })).toBe('[84]', 'The `JSON.stringify` callback function may return a number object when called on an array');
+    // Test 15.12.3@2-3-a-3.
+    expect(JSON.stringify([42], function (key, value) {
+      return value === 42 ? Object(false) : value;
+    })).toBe('[false]', 'The `JSON.stringify` callback function may return a Boolean object when called on an array');
+    // Test 15.12.3@4-1-2. 15.12.3@4-1-1 only tests whether an exception is
+    // thrown; the type of the exception is not checked.
+    value = {};
+    value.prop = value;
+    expect(stringify(value)).toError(TypeError, 'An object containing a circular reference should throw a `TypeError`');
+    // Test 15.12.3@4-1-3, modified to ensure that a `TypeError` is thrown.
+    value = {
+      p1: {
+        p2: {}
+      }
+    };
+    value.p1.p2.prop = value;
+    expect(stringify(value)).toError(TypeError, 'A nested cyclic structure should throw a `TypeError`');
+  });
+});