--- /dev/null
+"use strict";
+
+const isKeyframeSelector = require("../../utils/isKeyframeSelector");
+const isStandardSyntaxRule = require("../../utils/isStandardSyntaxRule");
+const isStandardSyntaxSelector = require("../../utils/isStandardSyntaxSelector");
+const isStandardSyntaxTypeSelector = require("../../utils/isStandardSyntaxTypeSelector");
+const parseSelector = require("../../utils/parseSelector");
+const report = require("../../utils/report");
+const ruleMessages = require("../../utils/ruleMessages");
+const validateOptions = require("../../utils/validateOptions");
+
+const ruleName = "selector-type-case";
+
+const messages = ruleMessages(ruleName, {
+ expected: (actual, expected) => `Expected "${actual}" to be "${expected}"`
+});
+
+const rule = function(expectation) {
+ return (root, result) => {
+ const validOptions = validateOptions(result, ruleName, {
+ actual: expectation,
+ possible: ["lower", "upper"]
+ });
+ if (!validOptions) {
+ return;
+ }
+
+ root.walkRules(rule => {
+ const selector = rule.selector,
+ selectors = rule.selectors;
+
+ if (!isStandardSyntaxRule(rule)) {
+ return;
+ }
+ if (!isStandardSyntaxSelector(selector)) {
+ return;
+ }
+ if (selectors.some(s => isKeyframeSelector(s))) {
+ return;
+ }
+
+ parseSelector(selector, result, rule, selectorAST => {
+ selectorAST.walkTags(tag => {
+ if (!isStandardSyntaxTypeSelector(tag)) {
+ return;
+ }
+
+ const sourceIndex = tag.sourceIndex,
+ value = tag.value;
+
+ const expectedValue =
+ expectation === "lower" ? value.toLowerCase() : value.toUpperCase();
+
+ if (value === expectedValue) {
+ return;
+ }
+
+ report({
+ message: messages.expected(value, expectedValue),
+ node: rule,
+ index: sourceIndex,
+ ruleName,
+ result
+ });
+ });
+ });
+ });
+ };
+};
+
+rule.ruleName = ruleName;
+rule.messages = messages;
+module.exports = rule;