207 lines
5.7 KiB
JavaScript
207 lines
5.7 KiB
JavaScript
/*
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
|
Author Tobias Koppers @sokra
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
const quoteMeta = str => {
|
|
return str.replace(/[-[\]\\/{}()*+?.^$|]/g, "\\$&");
|
|
};
|
|
|
|
const toSimpleString = str => {
|
|
if (`${+str}` === str) {
|
|
return str;
|
|
}
|
|
return JSON.stringify(str);
|
|
};
|
|
|
|
/**
|
|
* @param {Record<string|number, boolean>} map value map
|
|
* @returns {true|false|function(string): string} true/false, when unconditionally true/false, or a template function to determine the value at runtime
|
|
*/
|
|
const compileBooleanMatcher = map => {
|
|
const positiveItems = Object.keys(map).filter(i => map[i]);
|
|
const negativeItems = Object.keys(map).filter(i => !map[i]);
|
|
if (positiveItems.length === 0) return false;
|
|
if (negativeItems.length === 0) return true;
|
|
return compileBooleanMatcherFromLists(positiveItems, negativeItems);
|
|
};
|
|
|
|
/**
|
|
* @param {string[]} positiveItems positive items
|
|
* @param {string[]} negativeItems negative items
|
|
* @returns {function(string): string} a template function to determine the value at runtime
|
|
*/
|
|
const compileBooleanMatcherFromLists = (positiveItems, negativeItems) => {
|
|
if (positiveItems.length === 0) return () => "false";
|
|
if (negativeItems.length === 0) return () => "true";
|
|
if (positiveItems.length === 1)
|
|
return value => `${toSimpleString(positiveItems[0])} == ${value}`;
|
|
if (negativeItems.length === 1)
|
|
return value => `${toSimpleString(negativeItems[0])} != ${value}`;
|
|
const positiveRegexp = itemsToRegexp(positiveItems);
|
|
const negativeRegexp = itemsToRegexp(negativeItems);
|
|
if (positiveRegexp.length <= negativeRegexp.length) {
|
|
return value => `/^${positiveRegexp}$/.test(${value})`;
|
|
} else {
|
|
return value => `!/^${negativeRegexp}$/.test(${value})`;
|
|
}
|
|
};
|
|
|
|
const popCommonItems = (itemsSet, getKey, condition) => {
|
|
const map = new Map();
|
|
for (const item of itemsSet) {
|
|
const key = getKey(item);
|
|
if (key) {
|
|
let list = map.get(key);
|
|
if (list === undefined) {
|
|
list = [];
|
|
map.set(key, list);
|
|
}
|
|
list.push(item);
|
|
}
|
|
}
|
|
const result = [];
|
|
for (const list of map.values()) {
|
|
if (condition(list)) {
|
|
for (const item of list) {
|
|
itemsSet.delete(item);
|
|
}
|
|
result.push(list);
|
|
}
|
|
}
|
|
return result;
|
|
};
|
|
|
|
const getCommonPrefix = items => {
|
|
let prefix = items[0];
|
|
for (let i = 1; i < items.length; i++) {
|
|
const item = items[i];
|
|
for (let p = 0; p < prefix.length; p++) {
|
|
if (item[p] !== prefix[p]) {
|
|
prefix = prefix.slice(0, p);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return prefix;
|
|
};
|
|
|
|
const getCommonSuffix = items => {
|
|
let suffix = items[0];
|
|
for (let i = 1; i < items.length; i++) {
|
|
const item = items[i];
|
|
for (let p = item.length - 1, s = suffix.length - 1; s >= 0; p--, s--) {
|
|
if (item[p] !== suffix[s]) {
|
|
suffix = suffix.slice(s + 1);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return suffix;
|
|
};
|
|
|
|
const itemsToRegexp = itemsArr => {
|
|
if (itemsArr.length === 1) {
|
|
return quoteMeta(itemsArr[0]);
|
|
}
|
|
const finishedItems = [];
|
|
|
|
// merge single char items: (a|b|c|d|ef) => ([abcd]|ef)
|
|
let countOfSingleCharItems = 0;
|
|
for (const item of itemsArr) {
|
|
if (item.length === 1) {
|
|
countOfSingleCharItems++;
|
|
}
|
|
}
|
|
// special case for only single char items
|
|
if (countOfSingleCharItems === itemsArr.length) {
|
|
return `[${quoteMeta(itemsArr.sort().join(""))}]`;
|
|
}
|
|
const items = new Set(itemsArr.sort());
|
|
if (countOfSingleCharItems > 2) {
|
|
let singleCharItems = "";
|
|
for (const item of items) {
|
|
if (item.length === 1) {
|
|
singleCharItems += item;
|
|
items.delete(item);
|
|
}
|
|
}
|
|
finishedItems.push(`[${quoteMeta(singleCharItems)}]`);
|
|
}
|
|
|
|
// special case for 2 items with common prefix/suffix
|
|
if (finishedItems.length === 0 && items.size === 2) {
|
|
const prefix = getCommonPrefix(itemsArr);
|
|
const suffix = getCommonSuffix(
|
|
itemsArr.map(item => item.slice(prefix.length))
|
|
);
|
|
if (prefix.length > 0 || suffix.length > 0) {
|
|
return `${quoteMeta(prefix)}${itemsToRegexp(
|
|
itemsArr.map(i => i.slice(prefix.length, -suffix.length || undefined))
|
|
)}${quoteMeta(suffix)}`;
|
|
}
|
|
}
|
|
|
|
// special case for 2 items with common suffix
|
|
if (finishedItems.length === 0 && items.size === 2) {
|
|
const it = items[Symbol.iterator]();
|
|
const a = it.next().value;
|
|
const b = it.next().value;
|
|
if (a.length > 0 && b.length > 0 && a.slice(-1) === b.slice(-1)) {
|
|
return `${itemsToRegexp([a.slice(0, -1), b.slice(0, -1)])}${quoteMeta(
|
|
a.slice(-1)
|
|
)}`;
|
|
}
|
|
}
|
|
|
|
// find common prefix: (a1|a2|a3|a4|b5) => (a(1|2|3|4)|b5)
|
|
const prefixed = popCommonItems(
|
|
items,
|
|
item => (item.length >= 1 ? item[0] : false),
|
|
list => {
|
|
if (list.length >= 3) return true;
|
|
if (list.length <= 1) return false;
|
|
return list[0][1] === list[1][1];
|
|
}
|
|
);
|
|
for (const prefixedItems of prefixed) {
|
|
const prefix = getCommonPrefix(prefixedItems);
|
|
finishedItems.push(
|
|
`${quoteMeta(prefix)}${itemsToRegexp(
|
|
prefixedItems.map(i => i.slice(prefix.length))
|
|
)}`
|
|
);
|
|
}
|
|
|
|
// find common suffix: (a1|b1|c1|d1|e2) => ((a|b|c|d)1|e2)
|
|
const suffixed = popCommonItems(
|
|
items,
|
|
item => (item.length >= 1 ? item.slice(-1) : false),
|
|
list => {
|
|
if (list.length >= 3) return true;
|
|
if (list.length <= 1) return false;
|
|
return list[0].slice(-2) === list[1].slice(-2);
|
|
}
|
|
);
|
|
for (const suffixedItems of suffixed) {
|
|
const suffix = getCommonSuffix(suffixedItems);
|
|
finishedItems.push(
|
|
`${itemsToRegexp(
|
|
suffixedItems.map(i => i.slice(0, -suffix.length))
|
|
)}${quoteMeta(suffix)}`
|
|
);
|
|
}
|
|
|
|
// TODO further optimize regexp, i. e.
|
|
// use ranges: (1|2|3|4|a) => [1-4a]
|
|
const conditional = finishedItems.concat(Array.from(items, quoteMeta));
|
|
if (conditional.length === 1) return conditional[0];
|
|
return `(${conditional.join("|")})`;
|
|
};
|
|
|
|
compileBooleanMatcher.fromLists = compileBooleanMatcherFromLists;
|
|
compileBooleanMatcher.itemsToRegexp = itemsToRegexp;
|
|
module.exports = compileBooleanMatcher;
|