1  /* eslint-disable yoda */
 2  'use strict';
 3  
 4  const isFullwidthCodePoint = codePoint => {
 5  	if (Number.isNaN(codePoint)) {
 6  		return false;
 7  	}
 8  
 9  	// Code points are derived from:
10  	// http://www.unix.org/Public/UNIDATA/EastAsianWidth.txt
11  	if (
12  		codePoint >= 0x1100 && (
13  			codePoint <= 0x115F || // Hangul Jamo
14  			codePoint === 0x2329 || // LEFT-POINTING ANGLE BRACKET
15  			codePoint === 0x232A || // RIGHT-POINTING ANGLE BRACKET
16  			// CJK Radicals Supplement .. Enclosed CJK Letters and Months
17  			(0x2E80 <= codePoint && codePoint <= 0x3247 && codePoint !== 0x303F) ||
18  			// Enclosed CJK Letters and Months .. CJK Unified Ideographs Extension A
19  			(0x3250 <= codePoint && codePoint <= 0x4DBF) ||
20  			// CJK Unified Ideographs .. Yi Radicals
21  			(0x4E00 <= codePoint && codePoint <= 0xA4C6) ||
22  			// Hangul Jamo Extended-A
23  			(0xA960 <= codePoint && codePoint <= 0xA97C) ||
24  			// Hangul Syllables
25  			(0xAC00 <= codePoint && codePoint <= 0xD7A3) ||
26  			// CJK Compatibility Ideographs
27  			(0xF900 <= codePoint && codePoint <= 0xFAFF) ||
28  			// Vertical Forms
29  			(0xFE10 <= codePoint && codePoint <= 0xFE19) ||
30  			// CJK Compatibility Forms .. Small Form Variants
31  			(0xFE30 <= codePoint && codePoint <= 0xFE6B) ||
32  			// Halfwidth and Fullwidth Forms
33  			(0xFF01 <= codePoint && codePoint <= 0xFF60) ||
34  			(0xFFE0 <= codePoint && codePoint <= 0xFFE6) ||
35  			// Kana Supplement
36  			(0x1B000 <= codePoint && codePoint <= 0x1B001) ||
37  			// Enclosed Ideographic Supplement
38  			(0x1F200 <= codePoint && codePoint <= 0x1F251) ||
39  			// CJK Unified Ideographs Extension B .. Tertiary Ideographic Plane
40  			(0x20000 <= codePoint && codePoint <= 0x3FFFD)
41  		)
42  	) {
43  		return true;
44  	}
45  
46  	return false;
47  };
48  
49  module.exports = isFullwidthCodePoint;
50  module.exports.default = isFullwidthCodePoint;