Urara-Blog/node_modules/.pnpm-store/v3/files/81/4149acb14681b1420914bbb8621cc075f6c488cb2873e10f6bcf73881ca06ef45483188d029fa5473e95e1202fa338b41befad7b83fb10404c8f1f30851f4f
2022-08-14 01:14:53 +08:00

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Text

'use strict';
const { list } = require('postcss');
const { unit } = require('postcss-value-parser');
const stylehacks = require('stylehacks');
const canMerge = require('../canMerge.js');
const getDecls = require('../getDecls.js');
const getValue = require('../getValue.js');
const mergeRules = require('../mergeRules.js');
const insertCloned = require('../insertCloned.js');
const isCustomProp = require('../isCustomProp.js');
const canExplode = require('../canExplode.js');
const properties = ['column-width', 'column-count'];
const auto = 'auto';
const inherit = 'inherit';
/**
* Normalize a columns shorthand definition. Both of the longhand
* properties' initial values are 'auto', and as per the spec,
* omitted values are set to their initial values. Thus, we can
* remove any 'auto' definition when there are two values.
*
* Specification link: https://www.w3.org/TR/css3-multicol/
*
* @param {[string, string]} values
* @return {string}
*/
function normalize(values) {
if (values[0].toLowerCase() === auto) {
return values[1];
}
if (values[1].toLowerCase() === auto) {
return values[0];
}
if (
values[0].toLowerCase() === inherit &&
values[1].toLowerCase() === inherit
) {
return inherit;
}
return values.join(' ');
}
/**
* @param {import('postcss').Rule} rule
* @return {void}
*/
function explode(rule) {
rule.walkDecls(/^columns$/i, (decl) => {
if (!canExplode(decl)) {
return;
}
if (stylehacks.detect(decl)) {
return;
}
let values = list.space(decl.value);
if (values.length === 1) {
values.push(auto);
}
values.forEach((value, i) => {
let prop = properties[1];
const dimension = unit(value);
if (value.toLowerCase() === auto) {
prop = properties[i];
} else if (dimension && dimension.unit !== '') {
prop = properties[0];
}
insertCloned(/** @type {import('postcss').Rule} */ (decl.parent), decl, {
prop,
value,
});
});
decl.remove();
});
}
/**
* @param {import('postcss').Rule} rule
* @return {void}
*/
function cleanup(rule) {
let decls = getDecls(rule, ['columns'].concat(properties));
while (decls.length) {
const lastNode = decls[decls.length - 1];
// remove properties of lower precedence
const lesser = decls.filter(
(node) =>
!stylehacks.detect(lastNode) &&
!stylehacks.detect(node) &&
node !== lastNode &&
node.important === lastNode.important &&
lastNode.prop === 'columns' &&
node.prop !== lastNode.prop
);
for (const node of lesser) {
node.remove();
}
decls = decls.filter((node) => !lesser.includes(node));
// get duplicate properties
let duplicates = decls.filter(
(node) =>
!stylehacks.detect(lastNode) &&
!stylehacks.detect(node) &&
node !== lastNode &&
node.important === lastNode.important &&
node.prop === lastNode.prop &&
!(!isCustomProp(node) && isCustomProp(lastNode))
);
for (const node of duplicates) {
node.remove();
}
decls = decls.filter(
(node) => node !== lastNode && !duplicates.includes(node)
);
}
}
/**
* @param {import('postcss').Rule} rule
* @return {void}
*/
function merge(rule) {
mergeRules(rule, properties, (rules, lastNode) => {
if (canMerge(rules) && !rules.some(stylehacks.detect)) {
insertCloned(
/** @type {import('postcss').Rule} */ (lastNode.parent),
lastNode,
{
prop: 'columns',
value: normalize(/** @type [string, string] */ (rules.map(getValue))),
}
);
for (const node of rules) {
node.remove();
}
return true;
}
return false;
});
cleanup(rule);
}
module.exports = {
explode,
merge,
};