securityos/node_modules/regexp-tree/dist/optimizer/transforms/char-code-to-simple-char-tr...

84 lines
2.1 KiB
JavaScript

/**
* The MIT License (MIT)
* Copyright (c) 2017-present Dmitry Soshnikov <[email protected]>
*/
'use strict';
var UPPER_A_CP = 'A'.codePointAt(0);
var UPPER_Z_CP = 'Z'.codePointAt(0);
var LOWER_A_CP = 'a'.codePointAt(0);
var LOWER_Z_CP = 'z'.codePointAt(0);
var DIGIT_0_CP = '0'.codePointAt(0);
var DIGIT_9_CP = '9'.codePointAt(0);
/**
* A regexp-tree plugin to transform coded chars into simple chars.
*
* \u0061 -> a
*/
module.exports = {
Char: function Char(path) {
var node = path.node,
parent = path.parent;
if (isNaN(node.codePoint) || node.kind === 'simple') {
return;
}
if (parent.type === 'ClassRange') {
if (!isSimpleRange(parent)) {
return;
}
}
if (!isPrintableASCIIChar(node.codePoint)) {
return;
}
var symbol = String.fromCodePoint(node.codePoint);
var newChar = {
type: 'Char',
kind: 'simple',
value: symbol,
symbol: symbol,
codePoint: node.codePoint
};
if (needsEscape(symbol, parent.type)) {
newChar.escaped = true;
}
path.replace(newChar);
}
};
/**
* Checks if a range is included either in 0-9, a-z or A-Z
* @param classRange
* @returns {boolean}
*/
function isSimpleRange(classRange) {
var from = classRange.from,
to = classRange.to;
return from.codePoint >= DIGIT_0_CP && from.codePoint <= DIGIT_9_CP && to.codePoint >= DIGIT_0_CP && to.codePoint <= DIGIT_9_CP || from.codePoint >= UPPER_A_CP && from.codePoint <= UPPER_Z_CP && to.codePoint >= UPPER_A_CP && to.codePoint <= UPPER_Z_CP || from.codePoint >= LOWER_A_CP && from.codePoint <= LOWER_Z_CP && to.codePoint >= LOWER_A_CP && to.codePoint <= LOWER_Z_CP;
}
/**
* Checks if a code point in the range of printable ASCII chars
* (DEL char excluded)
* @param codePoint
* @returns {boolean}
*/
function isPrintableASCIIChar(codePoint) {
return codePoint >= 0x20 && codePoint <= 0x7e;
}
function needsEscape(symbol, parentType) {
if (parentType === 'ClassRange' || parentType === 'CharacterClass') {
return (/[\]\\^-]/.test(symbol)
);
}
return (/[*[()+?^$./\\|{}]/.test(symbol)
);
}