--- /dev/null
+"use strict";
+
+const _ = require("lodash");
+const isStandardSyntaxRule = require("../../utils/isStandardSyntaxRule");
+const isStandardSyntaxSelector = require("../../utils/isStandardSyntaxSelector");
+const report = require("../../utils/report");
+const ruleMessages = require("../../utils/ruleMessages");
+const validateOptions = require("../../utils/validateOptions");
+
+const ruleName = "selector-nested-pattern";
+
+const messages = ruleMessages(ruleName, {
+ expected: selector =>
+ `Expected nested selector "${selector}" to match specified pattern`
+});
+
+const rule = function(pattern) {
+ return (root, result) => {
+ const validOptions = validateOptions(result, ruleName, {
+ actual: pattern,
+ possible: [_.isRegExp, _.isString]
+ });
+ if (!validOptions) {
+ return;
+ }
+
+ const normalizedPattern = _.isString(pattern)
+ ? new RegExp(pattern)
+ : pattern;
+
+ root.walkRules(rule => {
+ if (rule.parent.type !== "rule") {
+ return;
+ }
+ if (!isStandardSyntaxRule(rule)) {
+ return;
+ }
+
+ const selector = rule.selector;
+
+ if (!isStandardSyntaxSelector(selector)) {
+ return;
+ }
+
+ if (normalizedPattern.test(selector)) {
+ return;
+ }
+
+ report({
+ result,
+ ruleName,
+ message: messages.expected(selector),
+ node: rule
+ });
+ });
+ };
+};
+
+rule.ruleName = ruleName;
+rule.messages = messages;
+module.exports = rule;