/usr/lib/nodejs/less/extend-visitor.js is in node-less 1.4.2-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 | (function (tree) {
tree.extendFinderVisitor = function() {
this._visitor = new tree.visitor(this);
this.contexts = [];
this.allExtendsStack = [[]];
};
tree.extendFinderVisitor.prototype = {
run: function (root) {
root = this._visitor.visit(root);
root.allExtends = this.allExtendsStack[0];
return root;
},
visitRule: function (ruleNode, visitArgs) {
visitArgs.visitDeeper = false;
},
visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
visitArgs.visitDeeper = false;
},
visitRuleset: function (rulesetNode, visitArgs) {
if (rulesetNode.root) {
return;
}
var i, j, extend, allSelectorsExtendList = [], extendList;
// get &:extend(.a); rules which apply to all selectors in this ruleset
for(i = 0; i < rulesetNode.rules.length; i++) {
if (rulesetNode.rules[i] instanceof tree.Extend) {
allSelectorsExtendList.push(rulesetNode.rules[i]);
}
}
// now find every selector and apply the extends that apply to all extends
// and the ones which apply to an individual extend
for(i = 0; i < rulesetNode.paths.length; i++) {
var selectorPath = rulesetNode.paths[i],
selector = selectorPath[selectorPath.length-1];
extendList = selector.extendList.slice(0).concat(allSelectorsExtendList).map(function(allSelectorsExtend) {
return allSelectorsExtend.clone();
});
for(j = 0; j < extendList.length; j++) {
this.foundExtends = true;
extend = extendList[j];
extend.findSelfSelectors(selectorPath);
extend.ruleset = rulesetNode;
if (j === 0) { extend.firstExtendOnThisSelectorPath = true; }
this.allExtendsStack[this.allExtendsStack.length-1].push(extend);
}
}
this.contexts.push(rulesetNode.selectors);
},
visitRulesetOut: function (rulesetNode) {
if (!rulesetNode.root) {
this.contexts.length = this.contexts.length - 1;
}
},
visitMedia: function (mediaNode, visitArgs) {
mediaNode.allExtends = [];
this.allExtendsStack.push(mediaNode.allExtends);
},
visitMediaOut: function (mediaNode) {
this.allExtendsStack.length = this.allExtendsStack.length - 1;
},
visitDirective: function (directiveNode, visitArgs) {
directiveNode.allExtends = [];
this.allExtendsStack.push(directiveNode.allExtends);
},
visitDirectiveOut: function (directiveNode) {
this.allExtendsStack.length = this.allExtendsStack.length - 1;
}
};
tree.processExtendsVisitor = function() {
this._visitor = new tree.visitor(this);
};
tree.processExtendsVisitor.prototype = {
run: function(root) {
var extendFinder = new tree.extendFinderVisitor();
extendFinder.run(root);
if (!extendFinder.foundExtends) { return root; }
root.allExtends = root.allExtends.concat(this.doExtendChaining(root.allExtends, root.allExtends));
this.allExtendsStack = [root.allExtends];
return this._visitor.visit(root);
},
doExtendChaining: function (extendsList, extendsListTarget, iterationCount) {
//
// chaining is different from normal extension.. if we extend an extend then we are not just copying, altering and pasting
// the selector we would do normally, but we are also adding an extend with the same target selector
// this means this new extend can then go and alter other extends
//
// this method deals with all the chaining work - without it, extend is flat and doesn't work on other extend selectors
// this is also the most expensive.. and a match on one selector can cause an extension of a selector we had already processed if
// we look at each selector at a time, as is done in visitRuleset
var extendIndex, targetExtendIndex, matches, extendsToAdd = [], newSelector, extendVisitor = this, selectorPath, extend, targetExtend, newExtend;
iterationCount = iterationCount || 0;
//loop through comparing every extend with every target extend.
// a target extend is the one on the ruleset we are looking at copy/edit/pasting in place
// e.g. .a:extend(.b) {} and .b:extend(.c) {} then the first extend extends the second one
// and the second is the target.
// the seperation into two lists allows us to process a subset of chains with a bigger set, as is the
// case when processing media queries
for(extendIndex = 0; extendIndex < extendsList.length; extendIndex++){
for(targetExtendIndex = 0; targetExtendIndex < extendsListTarget.length; targetExtendIndex++){
extend = extendsList[extendIndex];
targetExtend = extendsListTarget[targetExtendIndex];
// look for circular references
if (this.inInheritanceChain(targetExtend, extend)) { continue; }
// find a match in the target extends self selector (the bit before :extend)
selectorPath = [targetExtend.selfSelectors[0]];
matches = extendVisitor.findMatch(extend, selectorPath);
if (matches.length) {
// we found a match, so for each self selector..
extend.selfSelectors.forEach(function(selfSelector) {
// process the extend as usual
newSelector = extendVisitor.extendSelector(matches, selectorPath, selfSelector);
// but now we create a new extend from it
newExtend = new(tree.Extend)(targetExtend.selector, targetExtend.option, 0);
newExtend.selfSelectors = newSelector;
// add the extend onto the list of extends for that selector
newSelector[newSelector.length-1].extendList = [newExtend];
// record that we need to add it.
extendsToAdd.push(newExtend);
newExtend.ruleset = targetExtend.ruleset;
//remember its parents for circular references
newExtend.parents = [targetExtend, extend];
// only process the selector once.. if we have :extend(.a,.b) then multiple
// extends will look at the same selector path, so when extending
// we know that any others will be duplicates in terms of what is added to the css
if (targetExtend.firstExtendOnThisSelectorPath) {
newExtend.firstExtendOnThisSelectorPath = true;
targetExtend.ruleset.paths.push(newSelector);
}
});
}
}
}
if (extendsToAdd.length) {
// try to detect circular references to stop a stack overflow.
// may no longer be needed.
this.extendChainCount++;
if (iterationCount > 100) {
var selectorOne = "{unable to calculate}";
var selectorTwo = "{unable to calculate}";
try
{
selectorOne = extendsToAdd[0].selfSelectors[0].toCSS();
selectorTwo = extendsToAdd[0].selector.toCSS();
}
catch(e) {}
throw {message: "extend circular reference detected. One of the circular extends is currently:"+selectorOne+":extend(" + selectorTwo+")"};
}
// now process the new extends on the existing rules so that we can handle a extending b extending c ectending d extending e...
return extendsToAdd.concat(extendVisitor.doExtendChaining(extendsToAdd, extendsListTarget, iterationCount+1));
} else {
return extendsToAdd;
}
},
inInheritanceChain: function (possibleParent, possibleChild) {
if (possibleParent === possibleChild) {
return true;
}
if (possibleChild.parents) {
if (this.inInheritanceChain(possibleParent, possibleChild.parents[0])) {
return true;
}
if (this.inInheritanceChain(possibleParent, possibleChild.parents[1])) {
return true;
}
}
return false;
},
visitRule: function (ruleNode, visitArgs) {
visitArgs.visitDeeper = false;
},
visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
visitArgs.visitDeeper = false;
},
visitSelector: function (selectorNode, visitArgs) {
visitArgs.visitDeeper = false;
},
visitRuleset: function (rulesetNode, visitArgs) {
if (rulesetNode.root) {
return;
}
var matches, pathIndex, extendIndex, allExtends = this.allExtendsStack[this.allExtendsStack.length-1], selectorsToAdd = [], extendVisitor = this, selectorPath;
// look at each selector path in the ruleset, find any extend matches and then copy, find and replace
for(extendIndex = 0; extendIndex < allExtends.length; extendIndex++) {
for(pathIndex = 0; pathIndex < rulesetNode.paths.length; pathIndex++) {
selectorPath = rulesetNode.paths[pathIndex];
// extending extends happens initially, before the main pass
if (selectorPath[selectorPath.length-1].extendList.length) { continue; }
matches = this.findMatch(allExtends[extendIndex], selectorPath);
if (matches.length) {
allExtends[extendIndex].selfSelectors.forEach(function(selfSelector) {
selectorsToAdd.push(extendVisitor.extendSelector(matches, selectorPath, selfSelector));
});
}
}
}
rulesetNode.paths = rulesetNode.paths.concat(selectorsToAdd);
},
findMatch: function (extend, haystackSelectorPath) {
//
// look through the haystack selector path to try and find the needle - extend.selector
// returns an array of selector matches that can then be replaced
//
var haystackSelectorIndex, hackstackSelector, hackstackElementIndex, haystackElement,
targetCombinator, i,
extendVisitor = this,
needleElements = extend.selector.elements,
potentialMatches = [], potentialMatch, matches = [];
// loop through the haystack elements
for(haystackSelectorIndex = 0; haystackSelectorIndex < haystackSelectorPath.length; haystackSelectorIndex++) {
hackstackSelector = haystackSelectorPath[haystackSelectorIndex];
for(hackstackElementIndex = 0; hackstackElementIndex < hackstackSelector.elements.length; hackstackElementIndex++) {
haystackElement = hackstackSelector.elements[hackstackElementIndex];
// if we allow elements before our match we can add a potential match every time. otherwise only at the first element.
if (extend.allowBefore || (haystackSelectorIndex == 0 && hackstackElementIndex == 0)) {
potentialMatches.push({pathIndex: haystackSelectorIndex, index: hackstackElementIndex, matched: 0, initialCombinator: haystackElement.combinator});
}
for(i = 0; i < potentialMatches.length; i++) {
potentialMatch = potentialMatches[i];
// selectors add " " onto the first element. When we use & it joins the selectors together, but if we don't
// then each selector in haystackSelectorPath has a space before it added in the toCSS phase. so we need to work out
// what the resulting combinator will be
targetCombinator = haystackElement.combinator.value;
if (targetCombinator == '' && hackstackElementIndex === 0) {
targetCombinator = ' ';
}
// if we don't match, null our match to indicate failure
if (!extendVisitor.isElementValuesEqual(needleElements[potentialMatch.matched].value, haystackElement.value) ||
(potentialMatch.matched > 0 && needleElements[potentialMatch.matched].combinator.value !== targetCombinator)) {
potentialMatch = null;
} else {
potentialMatch.matched++;
}
// if we are still valid and have finished, test whether we have elements after and whether these are allowed
if (potentialMatch) {
potentialMatch.finished = potentialMatch.matched === needleElements.length;
if (potentialMatch.finished &&
(!extend.allowAfter && (hackstackElementIndex+1 < hackstackSelector.elements.length || haystackSelectorIndex+1 < haystackSelectorPath.length))) {
potentialMatch = null;
}
}
// if null we remove, if not, we are still valid, so either push as a valid match or continue
if (potentialMatch) {
if (potentialMatch.finished) {
potentialMatch.length = needleElements.length;
potentialMatch.endPathIndex = haystackSelectorIndex;
potentialMatch.endPathElementIndex = hackstackElementIndex + 1; // index after end of match
potentialMatches.length = 0; // we don't allow matches to overlap, so start matching again
matches.push(potentialMatch);
}
} else {
potentialMatches.splice(i, 1);
i--;
}
}
}
}
return matches;
},
isElementValuesEqual: function(elementValue1, elementValue2) {
if (typeof elementValue1 === "string" || typeof elementValue2 === "string") {
return elementValue1 === elementValue2;
}
if (elementValue1 instanceof tree.Attribute) {
if (elementValue1.op !== elementValue2.op || elementValue1.key !== elementValue2.key) {
return false;
}
if (!elementValue1.value || !elementValue2.value) {
if (elementValue1.value || elementValue2.value) {
return false;
}
return true;
}
elementValue1 = elementValue1.value.value || elementValue1.value;
elementValue2 = elementValue2.value.value || elementValue2.value;
return elementValue1 === elementValue2;
}
return false;
},
extendSelector:function (matches, selectorPath, replacementSelector) {
//for a set of matches, replace each match with the replacement selector
var currentSelectorPathIndex = 0,
currentSelectorPathElementIndex = 0,
path = [],
matchIndex,
selector,
firstElement,
match;
for (matchIndex = 0; matchIndex < matches.length; matchIndex++) {
match = matches[matchIndex];
selector = selectorPath[match.pathIndex];
firstElement = new tree.Element(
match.initialCombinator,
replacementSelector.elements[0].value,
replacementSelector.elements[0].index
);
if (match.pathIndex > currentSelectorPathIndex && currentSelectorPathElementIndex > 0) {
path[path.length - 1].elements = path[path.length - 1].elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
currentSelectorPathElementIndex = 0;
currentSelectorPathIndex++;
}
path = path.concat(selectorPath.slice(currentSelectorPathIndex, match.pathIndex));
path.push(new tree.Selector(
selector.elements
.slice(currentSelectorPathElementIndex, match.index)
.concat([firstElement])
.concat(replacementSelector.elements.slice(1))
));
currentSelectorPathIndex = match.endPathIndex;
currentSelectorPathElementIndex = match.endPathElementIndex;
if (currentSelectorPathElementIndex >= selector.elements.length) {
currentSelectorPathElementIndex = 0;
currentSelectorPathIndex++;
}
}
if (currentSelectorPathIndex < selectorPath.length && currentSelectorPathElementIndex > 0) {
path[path.length - 1].elements = path[path.length - 1].elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
currentSelectorPathElementIndex = 0;
currentSelectorPathIndex++;
}
path = path.concat(selectorPath.slice(currentSelectorPathIndex, selectorPath.length));
return path;
},
visitRulesetOut: function (rulesetNode) {
},
visitMedia: function (mediaNode, visitArgs) {
var newAllExtends = mediaNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length-1]);
newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, mediaNode.allExtends));
this.allExtendsStack.push(newAllExtends);
},
visitMediaOut: function (mediaNode) {
this.allExtendsStack.length = this.allExtendsStack.length - 1;
},
visitDirective: function (directiveNode, visitArgs) {
var newAllExtends = directiveNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length-1]);
newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, directiveNode.allExtends));
this.allExtendsStack.push(newAllExtends);
},
visitDirectiveOut: function (directiveNode) {
this.allExtendsStack.length = this.allExtendsStack.length - 1;
}
};
})(require('./tree'));
|