my-idlers/node_modules/clean-css/lib/optimizer/level-2/restructure.js

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var canReorderSingle = require('./reorderable').canReorderSingle;
var extractProperties = require('./extract-properties');
var isMergeable = require('./is-mergeable');
var tidyRuleDuplicates = require('./tidy-rule-duplicates');
var Token = require('../../tokenizer/token');
var cloneArray = require('../../utils/clone-array');
var serializeBody = require('../../writer/one-time').body;
var serializeRules = require('../../writer/one-time').rules;
function naturalSorter(a, b) {
return a > b ? 1 : -1;
}
function cloneAndMergeSelectors(propertyA, propertyB) {
var cloned = cloneArray(propertyA);
cloned[5] = cloned[5].concat(propertyB[5]);
return cloned;
}
function restructure(tokens, context) {
var options = context.options;
var mergeablePseudoClasses = options.compatibility.selectors.mergeablePseudoClasses;
var mergeablePseudoElements = options.compatibility.selectors.mergeablePseudoElements;
var mergeLimit = options.compatibility.selectors.mergeLimit;
var multiplePseudoMerging = options.compatibility.selectors.multiplePseudoMerging;
var specificityCache = context.cache.specificity;
var movableTokens = {};
var movedProperties = [];
var multiPropertyMoveCache = {};
var movedToBeDropped = [];
var maxCombinationsLevel = 2;
var ID_JOIN_CHARACTER = '%';
function sendToMultiPropertyMoveCache(position, movedProperty, allFits) {
for (var i = allFits.length - 1; i >= 0; i--) {
var fit = allFits[i][0];
var id = addToCache(movedProperty, fit);
if (multiPropertyMoveCache[id].length > 1 && processMultiPropertyMove(position, multiPropertyMoveCache[id])) {
removeAllMatchingFromCache(id);
break;
}
}
}
function addToCache(movedProperty, fit) {
var id = cacheId(fit);
multiPropertyMoveCache[id] = multiPropertyMoveCache[id] || [];
multiPropertyMoveCache[id].push([movedProperty, fit]);
return id;
}
function removeAllMatchingFromCache(matchId) {
var matchSelectors = matchId.split(ID_JOIN_CHARACTER);
var forRemoval = [];
var i;
for (var id in multiPropertyMoveCache) {
var selectors = id.split(ID_JOIN_CHARACTER);
for (i = selectors.length - 1; i >= 0; i--) {
if (matchSelectors.indexOf(selectors[i]) > -1) {
forRemoval.push(id);
break;
}
}
}
for (i = forRemoval.length - 1; i >= 0; i--) {
delete multiPropertyMoveCache[forRemoval[i]];
}
}
function cacheId(cachedTokens) {
var id = [];
for (var i = 0, l = cachedTokens.length; i < l; i++) {
id.push(serializeRules(cachedTokens[i][1]));
}
return id.join(ID_JOIN_CHARACTER);
}
function tokensToMerge(sourceTokens) {
var uniqueTokensWithBody = [];
var mergeableTokens = [];
for (var i = sourceTokens.length - 1; i >= 0; i--) {
if (!isMergeable(serializeRules(sourceTokens[i][1]), mergeablePseudoClasses, mergeablePseudoElements, multiplePseudoMerging)) {
continue;
}
mergeableTokens.unshift(sourceTokens[i]);
if (sourceTokens[i][2].length > 0 && uniqueTokensWithBody.indexOf(sourceTokens[i]) == -1)
uniqueTokensWithBody.push(sourceTokens[i]);
}
return uniqueTokensWithBody.length > 1 ?
mergeableTokens :
[];
}
function shortenIfPossible(position, movedProperty) {
var name = movedProperty[0];
var value = movedProperty[1];
var key = movedProperty[4];
var valueSize = name.length + value.length + 1;
var allSelectors = [];
var qualifiedTokens = [];
var mergeableTokens = tokensToMerge(movableTokens[key]);
if (mergeableTokens.length < 2)
return;
var allFits = findAllFits(mergeableTokens, valueSize, 1);
var bestFit = allFits[0];
if (bestFit[1] > 0)
return sendToMultiPropertyMoveCache(position, movedProperty, allFits);
for (var i = bestFit[0].length - 1; i >=0; i--) {
allSelectors = bestFit[0][i][1].concat(allSelectors);
qualifiedTokens.unshift(bestFit[0][i]);
}
allSelectors = tidyRuleDuplicates(allSelectors);
dropAsNewTokenAt(position, [movedProperty], allSelectors, qualifiedTokens);
}
function fitSorter(fit1, fit2) {
return fit1[1] > fit2[1] ? 1 : (fit1[1] == fit2[1] ? 0 : -1);
}
function findAllFits(mergeableTokens, propertySize, propertiesCount) {
var combinations = allCombinations(mergeableTokens, propertySize, propertiesCount, maxCombinationsLevel - 1);
return combinations.sort(fitSorter);
}
function allCombinations(tokensVariant, propertySize, propertiesCount, level) {
var differenceVariants = [[tokensVariant, sizeDifference(tokensVariant, propertySize, propertiesCount)]];
if (tokensVariant.length > 2 && level > 0) {
for (var i = tokensVariant.length - 1; i >= 0; i--) {
var subVariant = Array.prototype.slice.call(tokensVariant, 0);
subVariant.splice(i, 1);
differenceVariants = differenceVariants.concat(allCombinations(subVariant, propertySize, propertiesCount, level - 1));
}
}
return differenceVariants;
}
function sizeDifference(tokensVariant, propertySize, propertiesCount) {
var allSelectorsSize = 0;
for (var i = tokensVariant.length - 1; i >= 0; i--) {
allSelectorsSize += tokensVariant[i][2].length > propertiesCount ? serializeRules(tokensVariant[i][1]).length : -1;
}
return allSelectorsSize - (tokensVariant.length - 1) * propertySize + 1;
}
function dropAsNewTokenAt(position, properties, allSelectors, mergeableTokens) {
var i, j, k, m;
var allProperties = [];
for (i = mergeableTokens.length - 1; i >= 0; i--) {
var mergeableToken = mergeableTokens[i];
for (j = mergeableToken[2].length - 1; j >= 0; j--) {
var mergeableProperty = mergeableToken[2][j];
for (k = 0, m = properties.length; k < m; k++) {
var property = properties[k];
var mergeablePropertyName = mergeableProperty[1][1];
var propertyName = property[0];
var propertyBody = property[4];
if (mergeablePropertyName == propertyName && serializeBody([mergeableProperty]) == propertyBody) {
mergeableToken[2].splice(j, 1);
break;
}
}
}
}
for (i = properties.length - 1; i >= 0; i--) {
allProperties.unshift(properties[i][3]);
}
var newToken = [Token.RULE, allSelectors, allProperties];
tokens.splice(position, 0, newToken);
}
function dropPropertiesAt(position, movedProperty) {
var key = movedProperty[4];
var toMove = movableTokens[key];
if (toMove && toMove.length > 1) {
if (!shortenMultiMovesIfPossible(position, movedProperty))
shortenIfPossible(position, movedProperty);
}
}
function shortenMultiMovesIfPossible(position, movedProperty) {
var candidates = [];
var propertiesAndMergableTokens = [];
var key = movedProperty[4];
var j, k;
var mergeableTokens = tokensToMerge(movableTokens[key]);
if (mergeableTokens.length < 2)
return;
movableLoop:
for (var value in movableTokens) {
var tokensList = movableTokens[value];
for (j = mergeableTokens.length - 1; j >= 0; j--) {
if (tokensList.indexOf(mergeableTokens[j]) == -1)
continue movableLoop;
}
candidates.push(value);
}
if (candidates.length < 2)
return false;
for (j = candidates.length - 1; j >= 0; j--) {
for (k = movedProperties.length - 1; k >= 0; k--) {
if (movedProperties[k][4] == candidates[j]) {
propertiesAndMergableTokens.unshift([movedProperties[k], mergeableTokens]);
break;
}
}
}
return processMultiPropertyMove(position, propertiesAndMergableTokens);
}
function processMultiPropertyMove(position, propertiesAndMergableTokens) {
var valueSize = 0;
var properties = [];
var property;
for (var i = propertiesAndMergableTokens.length - 1; i >= 0; i--) {
property = propertiesAndMergableTokens[i][0];
var fullValue = property[4];
valueSize += fullValue.length + (i > 0 ? 1 : 0);
properties.push(property);
}
var mergeableTokens = propertiesAndMergableTokens[0][1];
var bestFit = findAllFits(mergeableTokens, valueSize, properties.length)[0];
if (bestFit[1] > 0)
return false;
var allSelectors = [];
var qualifiedTokens = [];
for (i = bestFit[0].length - 1; i >= 0; i--) {
allSelectors = bestFit[0][i][1].concat(allSelectors);
qualifiedTokens.unshift(bestFit[0][i]);
}
allSelectors = tidyRuleDuplicates(allSelectors);
dropAsNewTokenAt(position, properties, allSelectors, qualifiedTokens);
for (i = properties.length - 1; i >= 0; i--) {
property = properties[i];
var index = movedProperties.indexOf(property);
delete movableTokens[property[4]];
if (index > -1 && movedToBeDropped.indexOf(index) == -1)
movedToBeDropped.push(index);
}
return true;
}
function boundToAnotherPropertyInCurrrentToken(property, movedProperty, token) {
var propertyName = property[0];
var movedPropertyName = movedProperty[0];
if (propertyName != movedPropertyName)
return false;
var key = movedProperty[4];
var toMove = movableTokens[key];
return toMove && toMove.indexOf(token) > -1;
}
for (var i = tokens.length - 1; i >= 0; i--) {
var token = tokens[i];
var isRule;
var j, k, m;
var samePropertyAt;
if (token[0] == Token.RULE) {
isRule = true;
} else if (token[0] == Token.NESTED_BLOCK) {
isRule = false;
} else {
continue;
}
// We cache movedProperties.length as it may change in the loop
var movedCount = movedProperties.length;
var properties = extractProperties(token);
movedToBeDropped = [];
var unmovableInCurrentToken = [];
for (j = properties.length - 1; j >= 0; j--) {
for (k = j - 1; k >= 0; k--) {
if (!canReorderSingle(properties[j], properties[k], specificityCache)) {
unmovableInCurrentToken.push(j);
break;
}
}
}
for (j = properties.length - 1; j >= 0; j--) {
var property = properties[j];
var movedSameProperty = false;
for (k = 0; k < movedCount; k++) {
var movedProperty = movedProperties[k];
if (movedToBeDropped.indexOf(k) == -1 && (!canReorderSingle(property, movedProperty, specificityCache) && !boundToAnotherPropertyInCurrrentToken(property, movedProperty, token) ||
movableTokens[movedProperty[4]] && movableTokens[movedProperty[4]].length === mergeLimit)) {
dropPropertiesAt(i + 1, movedProperty);
if (movedToBeDropped.indexOf(k) == -1) {
movedToBeDropped.push(k);
delete movableTokens[movedProperty[4]];
}
}
if (!movedSameProperty) {
movedSameProperty = property[0] == movedProperty[0] && property[1] == movedProperty[1];
if (movedSameProperty) {
samePropertyAt = k;
}
}
}
if (!isRule || unmovableInCurrentToken.indexOf(j) > -1)
continue;
var key = property[4];
if (movedSameProperty && movedProperties[samePropertyAt][5].length + property[5].length > mergeLimit) {
dropPropertiesAt(i + 1, movedProperties[samePropertyAt]);
movedProperties.splice(samePropertyAt, 1);
movableTokens[key] = [token];
movedSameProperty = false;
} else {
movableTokens[key] = movableTokens[key] || [];
movableTokens[key].push(token);
}
if (movedSameProperty) {
movedProperties[samePropertyAt] = cloneAndMergeSelectors(movedProperties[samePropertyAt], property);
} else {
movedProperties.push(property);
}
}
movedToBeDropped = movedToBeDropped.sort(naturalSorter);
for (j = 0, m = movedToBeDropped.length; j < m; j++) {
var dropAt = movedToBeDropped[j] - j;
movedProperties.splice(dropAt, 1);
}
}
var position = tokens[0] && tokens[0][0] == Token.AT_RULE && tokens[0][1].indexOf('@charset') === 0 ? 1 : 0;
for (; position < tokens.length - 1; position++) {
var isImportRule = tokens[position][0] === Token.AT_RULE && tokens[position][1].indexOf('@import') === 0;
var isComment = tokens[position][0] === Token.COMMENT;
if (!(isImportRule || isComment))
break;
}
for (i = 0; i < movedProperties.length; i++) {
dropPropertiesAt(position, movedProperties[i]);
}
}
module.exports = restructure;