Update: no-constant-condition allows for narrower scope of varriable …

…arrays
eslint · Oct 7, 2019 · 5bc5562 · 5bc5562
1 parent b146b51
commit 5bc5562
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Showing 2 changed files with 6 additions and 5 deletions.
diff --git a/lib/rules/no-constant-condition.js b/lib/rules/no-constant-condition.js
@@ -91,10 +91,7 @@ module.exports = {
          */
         function isConstant(node, inBooleanPosition) {
 
-            /*
-             * Bug in espree (#425) causes [,] to return children of null
-             * so we need to check for existance until that is fixed
-             */
+            // node.elements can return null values in the case of sparse arrays ex. [,]
             if (!node) {
                 return true;
             }
@@ -106,7 +103,7 @@ module.exports = {
                     return true;
 
                 case "ArrayExpression": {
-                    if (inBooleanPosition) {
+                    if (!(node.parent.operator === "+")) {
                         return true;
                     }
                     return node.elements.every(element => isConstant(element, false));

diff --git a/tests/lib/rules/no-constant-condition.js b/tests/lib/rules/no-constant-condition.js
@@ -209,6 +209,10 @@ ruleTester.run("no-constant-condition", rule, {
         {
             code: "if(''+[]) {}",
             errors: [{ messageId: "unexpected", type: "BinaryExpression" }]
+        },
+        {
+            code: "if([a]==[a]) {}",
+            errors: [{ messageId: "unexpected", type: "BinaryExpression" }]
         }
     ]
 });