fix: false positive in literal-compare-order rule (#601)

Author: bmish

lib/rules/literal-compare-order.js

@@ -115,13 +115,11 @@ module.exports = {
             }
 
             /* istanbul ignore else: correctly does nothing */
-            if (
-                !assertVar ||
-                utils.isComparativeAssertion(node.callee, assertVar)
-            ) {
-                const compareActualFirst =
-                    !assertVar ||
-                    utils.shouldCompareActualFirst(node.callee, assertVar);
+            if (utils.isComparativeAssertion(node.callee, assertVar)) {
+                const compareActualFirst = utils.shouldCompareActualFirst(
+                    node.callee,
+                    assertVar,
+                );
                 checkLiteralCompareOrder(node.arguments, compareActualFirst);
             }
         }
@@ -137,10 +135,7 @@ module.exports = {
                     });
                 } else if (testStack.length > 0) {
                     const assertVar = getAssertContext();
-                    if (
-                        !assertVar ||
-                        utils.isAssertion(node.callee, assertVar)
-                    ) {
+                    if (utils.isAssertion(node.callee, assertVar)) {
                         processAssertion(node, assertVar);
                     }
                 }

lib/utils.js

@@ -76,7 +76,7 @@ exports.getAssertionNames = getAssertionNames;
 
 /**
  * @param {import('estree').Node} calleeNode
- * @param {string} assertVar
+ * @param {string | null} assertVar
  * @returns {{allowedArities: number[], compareActualFirst?: boolean} | null}
  */
 function getAssertionMetadata(calleeNode, assertVar) {
@@ -345,7 +345,7 @@ exports.getAssertContextName = function (functionExpr) {
 
 /**
  * @param {import('estree').Node} calleeNode
- * @param {string} assertVar
+ * @param {string | null} assertVar
  * @returns {boolean}
  */
 exports.isAssertion = function (calleeNode, assertVar) {
@@ -368,7 +368,7 @@ exports.getAllowedArities = function (calleeNode, assertVar) {
 
 /**
  * @param {import('estree').Node} calleeNode
- * @param {string} assertVar
+ * @param {string | null} assertVar
  * @returns {boolean}
  */
 exports.isComparativeAssertion = function (calleeNode, assertVar) {
@@ -379,7 +379,7 @@ exports.isComparativeAssertion = function (calleeNode, assertVar) {
 
 /**
  * @param {import('estree').Node} calleeNode
- * @param {string} assertVar
+ * @param {string | null} assertVar
  * @returns {boolean}
  */
 exports.shouldCompareActualFirst = function (calleeNode, assertVar) {

tests/lib/rules/literal-compare-order.js

@@ -86,6 +86,8 @@ ruleTester.run("literal-compare-order", rule, {
 
         // avoid crash in BDD-style assertions
         "QUnit.test('Name', function() { expect(variable).to.equal('Literal'); });",
+
+        "QUnit.test('Name', function() { router.on('routerDidChange', () => {}); });",
     ],
     invalid: [
         // equal