113 lines
3 KiB
JavaScript
113 lines
3 KiB
JavaScript
'use strict';
|
|
|
|
const keywords = new Map();
|
|
const properties = new Map();
|
|
const HYPHENMINUS = 45; // '-'.charCodeAt()
|
|
|
|
const keyword = getKeywordDescriptor;
|
|
const property = getPropertyDescriptor;
|
|
const vendorPrefix = getVendorPrefix;
|
|
function isCustomProperty(str, offset) {
|
|
offset = offset || 0;
|
|
|
|
return str.length - offset >= 2 &&
|
|
str.charCodeAt(offset) === HYPHENMINUS &&
|
|
str.charCodeAt(offset + 1) === HYPHENMINUS;
|
|
}
|
|
|
|
function getVendorPrefix(str, offset) {
|
|
offset = offset || 0;
|
|
|
|
// verdor prefix should be at least 3 chars length
|
|
if (str.length - offset >= 3) {
|
|
// vendor prefix starts with hyper minus following non-hyper minus
|
|
if (str.charCodeAt(offset) === HYPHENMINUS &&
|
|
str.charCodeAt(offset + 1) !== HYPHENMINUS) {
|
|
// vendor prefix should contain a hyper minus at the ending
|
|
const secondDashIndex = str.indexOf('-', offset + 2);
|
|
|
|
if (secondDashIndex !== -1) {
|
|
return str.substring(offset, secondDashIndex + 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
return '';
|
|
}
|
|
|
|
function getKeywordDescriptor(keyword) {
|
|
if (keywords.has(keyword)) {
|
|
return keywords.get(keyword);
|
|
}
|
|
|
|
const name = keyword.toLowerCase();
|
|
let descriptor = keywords.get(name);
|
|
|
|
if (descriptor === undefined) {
|
|
const custom = isCustomProperty(name, 0);
|
|
const vendor = !custom ? getVendorPrefix(name, 0) : '';
|
|
descriptor = Object.freeze({
|
|
basename: name.substr(vendor.length),
|
|
name,
|
|
prefix: vendor,
|
|
vendor,
|
|
custom
|
|
});
|
|
}
|
|
|
|
keywords.set(keyword, descriptor);
|
|
|
|
return descriptor;
|
|
}
|
|
|
|
function getPropertyDescriptor(property) {
|
|
if (properties.has(property)) {
|
|
return properties.get(property);
|
|
}
|
|
|
|
let name = property;
|
|
let hack = property[0];
|
|
|
|
if (hack === '/') {
|
|
hack = property[1] === '/' ? '//' : '/';
|
|
} else if (hack !== '_' &&
|
|
hack !== '*' &&
|
|
hack !== '$' &&
|
|
hack !== '#' &&
|
|
hack !== '+' &&
|
|
hack !== '&') {
|
|
hack = '';
|
|
}
|
|
|
|
const custom = isCustomProperty(name, hack.length);
|
|
|
|
// re-use result when possible (the same as for lower case)
|
|
if (!custom) {
|
|
name = name.toLowerCase();
|
|
if (properties.has(name)) {
|
|
const descriptor = properties.get(name);
|
|
properties.set(property, descriptor);
|
|
return descriptor;
|
|
}
|
|
}
|
|
|
|
const vendor = !custom ? getVendorPrefix(name, hack.length) : '';
|
|
const prefix = name.substr(0, hack.length + vendor.length);
|
|
const descriptor = Object.freeze({
|
|
basename: name.substr(prefix.length),
|
|
name: name.substr(hack.length),
|
|
hack,
|
|
vendor,
|
|
prefix,
|
|
custom
|
|
});
|
|
|
|
properties.set(property, descriptor);
|
|
|
|
return descriptor;
|
|
}
|
|
|
|
exports.isCustomProperty = isCustomProperty;
|
|
exports.keyword = keyword;
|
|
exports.property = property;
|
|
exports.vendorPrefix = vendorPrefix;
|