var hasOwnProperty = Object.prototype.hasOwnProperty;
|
|
function isEqualSelectors(a, b) {
|
var cursor1 = a.head;
|
var cursor2 = b.head;
|
|
while (cursor1 !== null && cursor2 !== null && cursor1.data.id === cursor2.data.id) {
|
cursor1 = cursor1.next;
|
cursor2 = cursor2.next;
|
}
|
|
return cursor1 === null && cursor2 === null;
|
}
|
|
function isEqualDeclarations(a, b) {
|
var cursor1 = a.head;
|
var cursor2 = b.head;
|
|
while (cursor1 !== null && cursor2 !== null && cursor1.data.id === cursor2.data.id) {
|
cursor1 = cursor1.next;
|
cursor2 = cursor2.next;
|
}
|
|
return cursor1 === null && cursor2 === null;
|
}
|
|
function compareDeclarations(declarations1, declarations2) {
|
var result = {
|
eq: [],
|
ne1: [],
|
ne2: [],
|
ne2overrided: []
|
};
|
|
var fingerprints = Object.create(null);
|
var declarations2hash = Object.create(null);
|
|
for (var cursor = declarations2.head; cursor; cursor = cursor.next) {
|
declarations2hash[cursor.data.id] = true;
|
}
|
|
for (var cursor = declarations1.head; cursor; cursor = cursor.next) {
|
var data = cursor.data;
|
|
if (data.fingerprint) {
|
fingerprints[data.fingerprint] = data.important;
|
}
|
|
if (declarations2hash[data.id]) {
|
declarations2hash[data.id] = false;
|
result.eq.push(data);
|
} else {
|
result.ne1.push(data);
|
}
|
}
|
|
for (var cursor = declarations2.head; cursor; cursor = cursor.next) {
|
var data = cursor.data;
|
|
if (declarations2hash[data.id]) {
|
// when declarations1 has an overriding declaration, this is not a difference
|
// unless no !important is used on prev and !important is used on the following
|
if (!hasOwnProperty.call(fingerprints, data.fingerprint) ||
|
(!fingerprints[data.fingerprint] && data.important)) {
|
result.ne2.push(data);
|
}
|
|
result.ne2overrided.push(data);
|
}
|
}
|
|
return result;
|
}
|
|
function addSelectors(dest, source) {
|
source.each(function(sourceData) {
|
var newStr = sourceData.id;
|
var cursor = dest.head;
|
|
while (cursor) {
|
var nextStr = cursor.data.id;
|
|
if (nextStr === newStr) {
|
return;
|
}
|
|
if (nextStr > newStr) {
|
break;
|
}
|
|
cursor = cursor.next;
|
}
|
|
dest.insert(dest.createItem(sourceData), cursor);
|
});
|
|
return dest;
|
}
|
|
// check if simpleselectors has no equal specificity and element selector
|
function hasSimilarSelectors(selectors1, selectors2) {
|
var cursor1 = selectors1.head;
|
|
while (cursor1 !== null) {
|
var cursor2 = selectors2.head;
|
|
while (cursor2 !== null) {
|
if (cursor1.data.compareMarker === cursor2.data.compareMarker) {
|
return true;
|
}
|
|
cursor2 = cursor2.next;
|
}
|
|
cursor1 = cursor1.next;
|
}
|
|
return false;
|
}
|
|
// test node can't to be skipped
|
function unsafeToSkipNode(node) {
|
switch (node.type) {
|
case 'Rule':
|
// unsafe skip ruleset with selector similarities
|
return hasSimilarSelectors(node.prelude.children, this);
|
|
case 'Atrule':
|
// can skip at-rules with blocks
|
if (node.block) {
|
// unsafe skip at-rule if block contains something unsafe to skip
|
return node.block.children.some(unsafeToSkipNode, this);
|
}
|
break;
|
|
case 'Declaration':
|
return false;
|
}
|
|
// unsafe by default
|
return true;
|
}
|
|
module.exports = {
|
isEqualSelectors: isEqualSelectors,
|
isEqualDeclarations: isEqualDeclarations,
|
compareDeclarations: compareDeclarations,
|
addSelectors: addSelectors,
|
hasSimilarSelectors: hasSimilarSelectors,
|
unsafeToSkipNode: unsafeToSkipNode
|
};
|
