xterm
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text/typescript
/**
* Copyright (c) 2016 The xterm.js authors. All rights reserved.
* @license MIT
*/
export const wcwidth = (function(opts: {nul: number, control: number}): (ucs: number) => number {
// extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
// combining characters
const COMBINING_BMP = [
[], [0x0483, 0x0486], [0x0488, 0x0489],
[], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
[], [0x05C7, 0x05C7], [0x0600, 0x0603],
[], [0x064B, 0x065E], [0x0670, 0x0670],
[], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
[], [0x0711, 0x0711], [0x0730, 0x074A],
[], [0x07EB, 0x07F3], [0x0901, 0x0902],
[], [0x0941, 0x0948], [0x094D, 0x094D],
[], [0x0962, 0x0963], [0x0981, 0x0981],
[], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
[], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
[], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
[], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
[], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
[], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
[], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
[], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
[], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
[], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
[], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
[], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
[], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
[], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
[], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
[], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
[], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
[], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
[], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
[], [0x1036, 0x1037], [0x1039, 0x1039],
[], [0x1160, 0x11FF], [0x135F, 0x135F],
[], [0x1732, 0x1734], [0x1752, 0x1753],
[], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
[], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
[], [0x18A9, 0x18A9], [0x1920, 0x1922],
[], [0x1932, 0x1932], [0x1939, 0x193B],
[], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
[], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
[], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
[], [0x202A, 0x202E], [0x2060, 0x2063],
[], [0x20D0, 0x20EF], [0x302A, 0x302F],
[], [0xA806, 0xA806], [0xA80B, 0xA80B],
[], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
[], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB],
];
const COMBINING_HIGH = [
[], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
[], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
[], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
[], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
[]
];
// binary search
function bisearch(ucs: number, data: number[][]): boolean {
let min = 0;
let max = data.length - 1;
let mid;
if (ucs < data[0][0] || ucs > data[max][1])
return false;
while (max >= min) {
mid = (min + max) >> 1;
if (ucs > data[mid][1])
min = mid + 1;
else if (ucs < data[mid][0])
max = mid - 1;
else
return true;
}
return false;
}
function wcwidthBMP(ucs: number): number {
// test for 8-bit control characters
if (ucs === 0)
return opts.nul;
if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
return opts.control;
// binary search in table of non-spacing characters
if (bisearch(ucs, COMBINING_BMP))
return 0;
// if we arrive here, ucs is not a combining or C0/C1 control character
if (isWideBMP(ucs)) {
return 2;
}
return 1;
}
function isWideBMP(ucs: number): boolean {
return (
ucs >= 0x1100 && (
ucs <= 0x115f || // Hangul Jamo init. consonants
ucs === 0x2329 ||
ucs === 0x232a ||
(ucs >= 0x2e80 && ucs <= 0xa4cf && ucs !== 0x303f) || // CJK..Yi
(ucs >= 0xac00 && ucs <= 0xd7a3) || // Hangul Syllables
(ucs >= 0xf900 && ucs <= 0xfaff) || // CJK Compat Ideographs
(ucs >= 0xfe10 && ucs <= 0xfe19) || // Vertical forms
(ucs >= 0xfe30 && ucs <= 0xfe6f) || // CJK Compat Forms
(ucs >= 0xff00 && ucs <= 0xff60) || // Fullwidth Forms
(ucs >= 0xffe0 && ucs <= 0xffe6)));
}
function wcwidthHigh(ucs: number): 0 | 1 | 2 {
if (bisearch(ucs, COMBINING_HIGH))
return 0;
if ((ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd)) {
return 2;
}
return 1;
}
const control = opts.control | 0;
let table: number[] | Uint32Array = null;
function init_table(): number[] | Uint32Array {
// lookup table for BMP
const CODEPOINTS = 65536; // BMP holds 65536 codepoints
const BITWIDTH = 2; // a codepoint can have a width of 0, 1 or 2
const ITEMSIZE = 32; // using uint32_t
const CONTAINERSIZE = CODEPOINTS * BITWIDTH / ITEMSIZE;
const CODEPOINTS_PER_ITEM = ITEMSIZE / BITWIDTH;
table = (typeof Uint32Array === 'undefined')
? new Array(CONTAINERSIZE)
: new Uint32Array(CONTAINERSIZE);
for (let i = 0; i < CONTAINERSIZE; ++i) {
let num = 0;
let pos = CODEPOINTS_PER_ITEM;
while (pos--)
num = (num << 2) | wcwidthBMP(CODEPOINTS_PER_ITEM * i + pos);
table[i] = num;
}
return table;
}
// get width from lookup table
// position in container : num / CODEPOINTS_PER_ITEM
// ==> n = table[Math.floor(num / 16)]
// ==> n = table[num >> 4]
// 16 codepoints per number: FFEEDDCCBBAA99887766554433221100
// position in number : (num % CODEPOINTS_PER_ITEM) * BITWIDTH
// ==> m = (n % 16) * 2
// ==> m = (num & 15) << 1
// right shift to position m
// ==> n = n >> m e.g. m=12 000000000000FFEEDDCCBBAA99887766
// we are only interested in 2 LSBs, cut off higher bits
// ==> n = n & 3 e.g. 000000000000000000000000000000XX
return function (num: number): number {
num = num | 0; // get asm.js like optimization under V8
if (num < 32)
return control | 0;
if (num < 127)
return 1;
let t = table || init_table();
if (num < 65536)
return t[num >> 4] >> ((num & 15) << 1) & 3;
// do a full search for high codepoints
return wcwidthHigh(num);
};
})({nul: 0, control: 0}); // configurable options