fix: do not report on shadowed constructors in no-new-wrappers (#17447

) * fix: do not report on shadowed constructors in `no-new-wrappers` * unit tests for undefined constructors
eslint · Aug 9, 2023 · 631648e · 631648e
1 parent 757bfe1
commit 631648e
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Showing 2 changed files with 67 additions and 8 deletions.
diff --git a/lib/rules/no-new-wrappers.js b/lib/rules/no-new-wrappers.js
@@ -5,6 +5,12 @@
 
 "use strict";
 
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const { getVariableByName } = require("./utils/ast-utils");
+
 //------------------------------------------------------------------------------
 // Rule Definition
 //------------------------------------------------------------------------------
@@ -28,18 +34,24 @@ module.exports = {
     },
 
     create(context) {
+        const { sourceCode } = context;
 
         return {
 
             NewExpression(node) {
                 const wrapperObjects = ["String", "Number", "Boolean"];
-
-                if (wrapperObjects.includes(node.callee.name)) {
-                    context.report({
-                        node,
-                        messageId: "noConstructor",
-                        data: { fn: node.callee.name }
-                    });
+                const { name } = node.callee;
+
+                if (wrapperObjects.includes(name)) {
+                    const variable = getVariableByName(sourceCode.getScope(node), name);
+
+                    if (variable && variable.identifiers.length === 0) {
+                        context.report({
+                            node,
+                            messageId: "noConstructor",
+                            data: { fn: name }
+                        });
+                    }
                 }
             }
         };

diff --git a/tests/lib/rules/no-new-wrappers.js b/tests/lib/rules/no-new-wrappers.js
@@ -21,7 +21,36 @@ const ruleTester = new RuleTester();
 ruleTester.run("no-new-wrappers", rule, {
     valid: [
         "var a = new Object();",
-        "var a = String('test'), b = String.fromCharCode(32);"
+        "var a = String('test'), b = String.fromCharCode(32);",
+        `
+        function test(Number) {
+            return new Number;
+        }
+        `,
+        {
+            code: `
+            import String from "./string";
+            const str = new String(42);
+            `,
+            parserOptions: { ecmaVersion: 6, sourceType: "module" }
+        },
+        `
+        if (foo) {
+            result = new Boolean(bar);
+        } else {
+            var Boolean = CustomBoolean;
+        }
+        `,
+        {
+            code: "new String()",
+            globals: {
+                String: "off"
+            }
+        },
+        `
+        /* global Boolean:off */
+        assert(new Boolean);
+        `
     ],
     invalid: [
         {
@@ -53,6 +82,24 @@ ruleTester.run("no-new-wrappers", rule, {
                 },
                 type: "NewExpression"
             }]
+        },
+        {
+            code: `
+            const a = new String('bar');
+            {
+                const String = CustomString;
+                const b = new String('foo');
+            }
+            `,
+            parserOptions: { ecmaVersion: 6 },
+            errors: [{
+                messageId: "noConstructor",
+                data: {
+                    fn: "String"
+                },
+                type: "NewExpression",
+                line: 2
+            }]
         }
     ]
 });