fix(template-require-mandatory-role-attributes): skip {{input}} semantic-role exemption in strict mode (Copilot review)

In classic Handlebars (.hbs), `{{input}}` globally resolves to Ember's
built-in input helper, which renders a native `<input>` — so the
semantic-role exemption (e.g., `role="switch"` on `{{input
type="checkbox"}}` is satisfied by the native `checked` property) is
correct.

In strict-mode GJS/GTS there is no lowercase `input` export from
`@ember/component` (only the PascalCase `<Input>` component), so
`{{input}}` in strict mode is always a user-bound identifier. We can't
prove it renders a native `<input>`, so applying the exemption risks
silently skipping required-ARIA checks on arbitrary components. Detect
strict mode by filename (matching the convention already established by
template-builtin-component-arguments) and return null for `{{input}}`
there; the regular required-ARIA flow then reports missing attributes.

Author: johanrd

lib/rules/template-require-mandatory-role-attributes.js

@@ -53,22 +53,30 @@ function getStaticAttrValue(node, name) {
   return undefined;
 }
 
-function getTagName(node) {
+// In classic Handlebars (.hbs) `{{input}}` globally resolves to Ember's
+// built-in input helper, which renders a native <input>. In strict-mode
+// GJS/GTS there is no corresponding lowercase `input` export from
+// `@ember/component` (only the PascalCase `<Input>` component), so
+// `{{input}}` in strict mode is always a user-bound identifier and cannot
+// be assumed to render a native <input>. Treating it as native there
+// would silently skip required-ARIA checks on arbitrary components.
+function isClassicHbsFilename(context) {
+  const filename = context.filename || context.getFilename?.() || '';
+  return !filename.endsWith('.gjs') && !filename.endsWith('.gts');
+}
+
+function getTagName(node, context) {
   if (node?.type === 'GlimmerElementNode') {
     // HTML tag names are case-insensitive; normalize so <INPUT>/<Input> match
     // the lowercase keys in AX_CONCEPTS_BY_TAG and the semantic-role maps.
     return node.tag?.toLowerCase();
   }
   if (node?.type === 'GlimmerMustacheStatement' && node.path?.original === 'input') {
-    // The classic `{{input}}` helper renders a native <input>.
-    //
-    // Caveat: in strict GJS/GTS mode, `{{input}}` is whatever was imported
-    // under the name `input` — it could be the classic helper (still renders
-    // native <input>) or some user-defined component. We assume the classic
-    // helper; the false-positive rate in practice is low because strict-mode
-    // authors rarely use `{{input}}` at all (idiomatic is <input> or
-    // <Input>), and when they do, it's almost always the imported built-in.
-    return 'input';
+    if (!context || isClassicHbsFilename(context)) {
+      return 'input';
+    }
+    // Strict-mode {{input}} — not the classic helper, can't claim native.
+    return null;
   }
   return null;
 }
@@ -111,8 +119,8 @@ function buildAxConceptsByTag() {
   return index;
 }
 
-function isSemanticRoleElement(node, role) {
-  const tag = getTagName(node);
+function isSemanticRoleElement(node, role, context) {
+  const tag = getTagName(node, context);
   if (!tag || typeof role !== 'string') {
     return false;
   }
@@ -153,14 +161,14 @@ function isSemanticRoleElement(node, role) {
 // type=checkbox role=switch>), the element is exempt: return { role, missing: null }.
 //
 // Diverges from jsx-a11y, which validates every recognised token.
-function getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node) {
+function getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node, context) {
   for (const role of roleTokens) {
     const roleDefinition = roles.get(role);
     if (!roleDefinition || roleDefinition.abstract) {
       continue;
     }
     // Semantic-role elements expose required ARIA state natively — skip.
-    if (isSemanticRoleElement(node, role)) {
+    if (isSemanticRoleElement(node, role, context)) {
       return { role, missing: null };
     }
     const requiredAttributes = Object.keys(roleDefinition.requiredProps);
@@ -227,7 +235,7 @@ module.exports = {
           .filter((attribute) => attribute.name?.startsWith('aria-'))
           .map((attribute) => attribute.name);
 
-        const result = getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node);
+        const result = getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node, context);
 
         if (result?.missing) {
           reportMissingAttributes(node, result.role, result.missing);
@@ -245,7 +253,7 @@ module.exports = {
           .filter((pair) => pair.key.startsWith('aria-'))
           .map((pair) => pair.key);
 
-        const result = getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node);
+        const result = getMissingRequiredAttributes(roleTokens, foundAriaAttributes, node, context);
 
         if (result?.missing) {
           reportMissingAttributes(node, result.role, result.missing);

tests/lib/rules/template-require-mandatory-role-attributes.js

@@ -193,6 +193,30 @@ ruleTester.run('template-require-mandatory-role-attributes', rule, {
         },
       ],
     },
+    // Strict-mode {{input}} is a scope binding, not Ember's classic helper
+    // (which doesn't exist as a strict-mode export from @ember/component).
+    // The semantic-role exemption must NOT apply — we can't prove the
+    // imported identifier renders a native <input>. Flag the missing ARIA.
+    {
+      code: '<template>{{input type="checkbox" role="switch"}}</template>',
+      filename: 'component.gjs',
+      output: null,
+      errors: [
+        {
+          message: 'The attribute aria-checked is required by the role switch',
+        },
+      ],
+    },
+    {
+      code: '<template>{{input type="range" role="slider"}}</template>',
+      filename: 'component.gts',
+      output: null,
+      errors: [
+        {
+          message: 'The attribute aria-valuenow is required by the role slider',
+        },
+      ],
+    },
   ],
 });