Sharkey/src/mfm/syntax-highlight.ts
2018-12-21 11:28:30 +09:00

343 lines
5.8 KiB
TypeScript

import { capitalize, toUpperCase } from '../prelude/string';
function escape(text: string) {
return text
.replace(/>/g, '>')
.replace(/</g, '&lt;');
}
// 文字数が多い順にソートします
// そうしないと、「function」という文字列が与えられたときに「func」が先にマッチしてしまう可能性があるためです
const _keywords = [
'true',
'false',
'null',
'nil',
'undefined',
'void',
'var',
'const',
'let',
'mut',
'dim',
'if',
'then',
'else',
'switch',
'match',
'case',
'default',
'for',
'each',
'in',
'while',
'loop',
'continue',
'break',
'do',
'goto',
'next',
'end',
'sub',
'throw',
'try',
'catch',
'finally',
'enum',
'delegate',
'function',
'func',
'fun',
'fn',
'return',
'yield',
'async',
'await',
'require',
'include',
'import',
'imports',
'export',
'exports',
'from',
'as',
'using',
'use',
'internal',
'module',
'namespace',
'where',
'select',
'struct',
'union',
'new',
'delete',
'this',
'super',
'base',
'class',
'interface',
'abstract',
'static',
'public',
'private',
'protected',
'virtual',
'partial',
'override',
'extends',
'implements',
'constructor'
];
const keywords = _keywords
.concat(_keywords.map(capitalize))
.concat(_keywords.map(toUpperCase))
.sort((a, b) => b.length - a.length);
const symbols = [
'=',
'+',
'-',
'*',
'/',
'%',
'~',
'^',
'&',
'|',
'>',
'<',
'!',
'?'
];
type Token = {
html: string
next: number
};
type Element = (code: string, i: number, source: string) => (Token | null);
const elements: Element[] = [
// comment
code => {
if (code.substr(0, 2) != '//') return null;
const match = code.match(/^\/\/(.+?)(\n|$)/);
if (!match) return null;
const comment = match[0];
return {
html: `<span class="comment">${escape(comment)}</span>`,
next: comment.length
};
},
// block comment
code => {
const match = code.match(/^\/\*([\s\S]+?)\*\//);
if (!match) return null;
return {
html: `<span class="comment">${escape(match[0])}</span>`,
next: match[0].length
};
},
// string
code => {
if (!/^['"`]/.test(code)) return null;
const begin = code[0];
let str = begin;
let thisIsNotAString = false;
for (let i = 1; i < code.length; i++) {
const char = code[i];
if (char == '\\') {
str += char;
str += code[i + 1] || '';
i++;
continue;
} else if (char == begin) {
str += char;
break;
} else if (char == '\n' || i == (code.length - 1)) {
thisIsNotAString = true;
break;
} else {
str += char;
}
}
if (thisIsNotAString) {
return null;
} else {
return {
html: `<span class="string">${escape(str)}</span>`,
next: str.length
};
}
},
// regexp
code => {
if (code[0] != '/') return null;
let regexp = '';
let thisIsNotARegexp = false;
for (let i = 1; i < code.length; i++) {
const char = code[i];
if (char == '\\') {
regexp += char;
regexp += code[i + 1] || '';
i++;
continue;
} else if (char == '/') {
break;
} else if (char == '\n' || i == (code.length - 1)) {
thisIsNotARegexp = true;
break;
} else {
regexp += char;
}
}
if (thisIsNotARegexp) return null;
if (regexp == '') return null;
if (regexp.startsWith(' ') && regexp.endsWith(' ')) return null;
return {
html: `<span class="regexp">/${escape(regexp)}/</span>`,
next: regexp.length + 2
};
},
// label
code => {
if (code[0] != '@') return null;
const match = code.match(/^@([a-zA-Z_-]+?)\n/);
if (!match) return null;
const label = match[0];
return {
html: `<span class="label">${label}</span>`,
next: label.length
};
},
// number
(code, i, source) => {
const prev = source[i - 1];
if (prev && /[a-zA-Z]/.test(prev)) return null;
if (!/^[\-\+]?[0-9\.]+/.test(code)) return null;
const match = code.match(/^[\-\+]?[0-9\.]+/)[0];
if (match) {
return {
html: `<span class="number">${match}</span>`,
next: match.length
};
} else {
return null;
}
},
// nan
(code, i, source) => {
const prev = source[i - 1];
if (prev && /[a-zA-Z]/.test(prev)) return null;
if (code.substr(0, 3) == 'NaN') {
return {
html: `<span class="nan">NaN</span>`,
next: 3
};
} else {
return null;
}
},
// method
code => {
const match = code.match(/^([a-zA-Z_-]+?)\(/);
if (!match) return null;
if (match[1] == '-') return null;
return {
html: `<span class="method">${match[1]}</span>`,
next: match[1].length
};
},
// property
(code, i, source) => {
const prev = source[i - 1];
if (prev != '.') return null;
const match = code.match(/^[a-zA-Z0-9_-]+/);
if (!match) return null;
return {
html: `<span class="property">${match[0]}</span>`,
next: match[0].length
};
},
// keyword
(code, i, source) => {
const prev = source[i - 1];
if (prev && /[a-zA-Z]/.test(prev)) return null;
const match = keywords.filter(k => code.substr(0, k.length) == k)[0];
if (match) {
if (/^[a-zA-Z]/.test(code.substr(match.length))) return null;
return {
html: `<span class="keyword ${match}">${match}</span>`,
next: match.length
};
} else {
return null;
}
},
// symbol
code => {
const match = symbols.filter(s => code[0] == s)[0];
if (match) {
return {
html: `<span class="symbol">${match}</span>`,
next: 1
};
} else {
return null;
}
}
];
// TODO: specify lang
export default (source: string, lang?: string): string => {
let code = source;
let html = '';
let i = 0;
function push(token: Token) {
html += token.html;
code = code.substr(token.next);
i += token.next;
}
while (code != '') {
const parsed = elements.some(el => {
const e = el(code, i, source);
if (e) {
push(e);
return true;
} else {
return false;
}
});
if (!parsed) {
push({
html: escape(code[0]),
next: 1
});
}
}
return html;
};