Fix: skip argument validation when builtin names are shadowed by JS imports

In gjs/gts files, when a developer imports a custom component with a name
that matches an Ember built-in (Input, Textarea, LinkTo), the rule would
incorrectly flag unknown arguments. This checks scope analysis to determine
if the tag name resolves to a JS-scope variable with a definition (e.g. an
import binding), and skips validation in that case.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Author: NullVoxPopuli

lib/rules/template-no-unknown-arguments-for-builtin-components.js

@@ -364,6 +364,8 @@ module.exports = {
   },
 
   create(context) {
+    const sourceCode = context.sourceCode;
+
     return {
       GlimmerElementNode(node) {
         if (!node.tag || !node.attributes) {
@@ -375,6 +377,22 @@ module.exports = {
           return;
         }
 
+        // In gjs/gts, if the tag name resolves to a JS-scope variable with a
+        // definition (e.g. an import or local variable), then it shadows the
+        // Ember built-in component — skip validation.
+        if (node.parent && node.parts && node.parts[0]) {
+          const scope = sourceCode.getScope(node.parent);
+          const isShadowed = scope.references.some(
+            (ref) =>
+              ref.identifier === node.parts[0] &&
+              ref.resolved &&
+              ref.resolved.defs.length > 0
+          );
+          if (isShadowed) {
+            return;
+          }
+        }
+
         const seen = [];
         const warns = [];
 

tests/lib/rules/template-no-unknown-arguments-for-builtin-components.js

@@ -39,6 +39,38 @@ ruleTester.run('template-no-unknown-arguments-for-builtin-components', rule, {
     '<template><LinkTo @query={{hash foo=bar}} /></template>',
     '<template><LinkTo @model={{this.model}} /></template>',
     '<template><LinkTo @models={{array comment.photo comment}} /></template>',
+
+    // Custom component imported with the same name as a built-in — should NOT be flagged
+    {
+      filename: 'my-component.gjs',
+      code: `
+        import Input from './my-custom-input';
+        <template><Input @unknownArg="x" /></template>
+      `,
+    },
+    {
+      filename: 'my-component.gjs',
+      code: `
+        import Textarea from './my-custom-textarea';
+        <template><Textarea @customProp={{this.val}} /></template>
+      `,
+    },
+    {
+      filename: 'my-component.gjs',
+      code: `
+        import LinkTo from './my-custom-link';
+        <template><LinkTo @anythingGoes="yes" /></template>
+      `,
+    },
+    {
+      filename: 'my-component.gjs',
+      code: `
+        import Input from './my-custom-input';
+        export default class MyComponent {
+          <template><Input @customArg="value" @anotherArg={{this.foo}} /></template>
+        }
+      `,
+    },
   ],
 
   invalid: [