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2020-11-01 22:46:04 +00:00

141 lines
3.9 KiB
JavaScript

// @ts-nocheck
'use strict';
const _ = require('lodash');
const findAtRuleContext = require('../../utils/findAtRuleContext');
const isCustomPropertySet = require('../../utils/isCustomPropertySet');
const isStandardSyntaxRule = require('../../utils/isStandardSyntaxRule');
const isStandardSyntaxSelector = require('../../utils/isStandardSyntaxSelector');
const keywordSets = require('../../reference/keywordSets');
const nodeContextLookup = require('../../utils/nodeContextLookup');
const optionsMatches = require('../../utils/optionsMatches');
const parseSelector = require('../../utils/parseSelector');
const report = require('../../utils/report');
const resolvedNestedSelector = require('postcss-resolve-nested-selector');
const ruleMessages = require('../../utils/ruleMessages');
const specificity = require('specificity');
const validateOptions = require('../../utils/validateOptions');
const ruleName = 'no-descending-specificity';
const messages = ruleMessages(ruleName, {
rejected: (b, a) => `Expected selector "${b}" to come before selector "${a}"`,
});
function rule(on, options) {
return (root, result) => {
const validOptions = validateOptions(
result,
ruleName,
{
actual: on,
},
{
optional: true,
actual: options,
possible: {
ignore: ['selectors-within-list'],
},
},
);
if (!validOptions) {
return;
}
const selectorContextLookup = nodeContextLookup();
root.walkRules((rule) => {
// Ignore custom property set `--foo: {};`
if (isCustomPropertySet(rule)) {
return;
}
// Ignore nested property `foo: {};`
if (!isStandardSyntaxRule(rule)) {
return;
}
// Ignores selectors within list of selectors
if (optionsMatches(options, 'ignore', 'selectors-within-list') && rule.selectors.length > 1) {
return;
}
const comparisonContext = selectorContextLookup.getContext(rule, findAtRuleContext(rule));
rule.selectors.forEach((selector) => {
const trimSelector = selector.trim();
// Ignore `.selector, { }`
if (trimSelector === '') {
return;
}
// The edge-case of duplicate selectors will act acceptably
const index = rule.selector.indexOf(trimSelector);
// Resolve any nested selectors before checking
resolvedNestedSelector(selector, rule).forEach((resolvedSelector) => {
parseSelector(resolvedSelector, result, rule, (s) => {
if (!isStandardSyntaxSelector(resolvedSelector)) {
return;
}
checkSelector(s, rule, index, comparisonContext);
});
});
});
});
function checkSelector(selectorNode, rule, sourceIndex, comparisonContext) {
const selector = selectorNode.toString();
const referenceSelectorNode = lastCompoundSelectorWithoutPseudoClasses(selectorNode);
const selectorSpecificity = specificity.calculate(selector)[0].specificityArray;
const entry = { selector, specificity: selectorSpecificity };
if (!comparisonContext.has(referenceSelectorNode)) {
comparisonContext.set(referenceSelectorNode, [entry]);
return;
}
const priorComparableSelectors = comparisonContext.get(referenceSelectorNode);
priorComparableSelectors.forEach((priorEntry) => {
if (specificity.compare(selectorSpecificity, priorEntry.specificity) === -1) {
report({
ruleName,
result,
node: rule,
message: messages.rejected(selector, priorEntry.selector),
index: sourceIndex,
});
}
});
priorComparableSelectors.push(entry);
}
};
}
function lastCompoundSelectorWithoutPseudoClasses(selectorNode) {
const nodesAfterLastCombinator = _.last(
selectorNode.nodes[0].split((node) => {
return node.type === 'combinator';
}),
);
const nodesWithoutPseudoClasses = nodesAfterLastCombinator
.filter((node) => {
return node.type !== 'pseudo' || keywordSets.pseudoElements.has(node.value.replace(/:/g, ''));
})
.join('');
return nodesWithoutPseudoClasses.toString();
}
rule.ruleName = ruleName;
rule.messages = messages;
module.exports = rule;