[RegExp] Match updated spec for `/\w/iu` and `/\W/iu`

[mathiasbynens]

Now that tc39/ecma262#525 has landed, \u017F (LATIN SMALL LETTER LONG S) and \u212A (KELVIN SIGN) are word characters for /iu patterns.

Expected vs. actual behavior:

/\w/iu.test('\u017F') // true
/\w/iu.test('\u212A') // true
/\W/iu.test('\u017F') // false, actual: true
/\W/iu.test('\u212A') // false, actual: true
/\W/iu.test('s')      // false
/\W/iu.test('S')      // false
/\W/iu.test('K')      // false
/\W/iu.test('k')      // false

See also

• V8: https://bugs.chromium.org/p/v8/issues/detail?id=5145
• JavaScriptCore: https://bugs.webkit.org/show_bug.cgi?id=159055
• SpiderMonkey: https://bugzilla.mozilla.org/show_bug.cgi?id=1281739
• regexpu-core: Match updated spec for /\w/iu and /\W/iu  mathiasbynens/regexpu-core#8

[dilijev]

Related to #517

[dilijev]

Just to clarify, I'm seeing in the following in ChakraCore for actual behavior.

/\w/iu.test('\u017F') // expected: true,  actual: false ***
/\w/iu.test('\u212A') // expected: true,  actual: false ***
/\W/iu.test('\u017F') // expected: false, actual: true
/\W/iu.test('\u212A') // expected: false, actual: true
/\W/iu.test('s')      // expected: false
/\W/iu.test('S')      // expected: false
/\W/iu.test('K')      // expected: false
/\W/iu.test('k')      // expected: false

Since sharp s and kelvin are word characters, \w should match those two characters (first two lines above).
Also since \W should be the inverse set of \w, \W does not match those characters. Correct?