From c340132e56c3007c5e80db14644e437f4f3e9aa0 Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Tue, 10 Mar 2026 18:23:32 -0400
Subject: [PATCH 1/2] Extract rule: template-deprecated-render-helper

---
 README.md                                     |  1 +
 .../template-deprecated-render-helper.md      | 25 ++++++
 .../template-deprecated-render-helper.js      | 49 +++++++++++
 .../template-deprecated-render-helper.js      | 85 +++++++++++++++++++
 4 files changed, 160 insertions(+)
 create mode 100644 docs/rules/template-deprecated-render-helper.md
 create mode 100644 lib/rules/template-deprecated-render-helper.js
 create mode 100644 tests/lib/rules/template-deprecated-render-helper.js

diff --git a/README.md b/README.md
index d63131fbd2..2abdf640df 100644
--- a/README.md
+++ b/README.md
@@ -292,6 +292,7 @@ rules in templates can be disabled with eslint directives with mustache or html
 | [no-old-shims](docs/rules/no-old-shims.md)                                                       | disallow usage of old shims for modules                   | ✅  | 🔧 |    |
 | [no-string-prototype-extensions](docs/rules/no-string-prototype-extensions.md)                   | disallow usage of `String` prototype extensions           | ✅  |    |    |
 | [template-deprecated-inline-view-helper](docs/rules/template-deprecated-inline-view-helper.md)   | disallow inline {{view}} helper                           |    | 🔧 |    |
+| [template-deprecated-render-helper](docs/rules/template-deprecated-render-helper.md)             | disallow {{render}} helper                                |    |    |    |
 | [template-no-action](docs/rules/template-no-action.md)                                           | disallow {{action}} helper                                |    |    |    |
 | [template-no-attrs-in-components](docs/rules/template-no-attrs-in-components.md)                 | disallow attrs in component templates                     |    |    |    |
 | [template-no-link-to-positional-params](docs/rules/template-no-link-to-positional-params.md)     | disallow positional params in LinkTo component            |    |    |    |
diff --git a/docs/rules/template-deprecated-render-helper.md b/docs/rules/template-deprecated-render-helper.md
new file mode 100644
index 0000000000..c0fb7dbcc8
--- /dev/null
+++ b/docs/rules/template-deprecated-render-helper.md
@@ -0,0 +1,25 @@
+# ember/template-deprecated-render-helper
+
+> **HBS Only**: This rule applies to classic `.hbs` template files only (loose mode). It is not relevant for `gjs`/`gts` files (strict mode), where these patterns cannot occur.
+
+<!-- end auto-generated rule header -->
+
+Disallows the {{render}} helper which is deprecated.
+
+## Examples
+
+Incorrect:
+
+```hbs
+{{render 'user'}}
+```
+
+Correct:
+
+```hbs
+<User />
+```
+
+## References
+
+- [eslint-plugin-ember template-deprecated-render-helper](https://github.com/ember-cli/eslint-plugin-ember/blob/master/docs/rules/template-deprecated-render-helper.md)
diff --git a/lib/rules/template-deprecated-render-helper.js b/lib/rules/template-deprecated-render-helper.js
new file mode 100644
index 0000000000..6874ae80b9
--- /dev/null
+++ b/lib/rules/template-deprecated-render-helper.js
@@ -0,0 +1,49 @@
+/** @type {import('eslint').Rule.RuleModule} */
+module.exports = {
+  meta: {
+    type: 'suggestion',
+    docs: {
+      description: 'disallow {{render}} helper',
+      category: 'Deprecations',
+      url: 'https://github.com/ember-cli/eslint-plugin-ember/tree/master/docs/rules/template-deprecated-render-helper.md',
+      templateMode: 'loose',
+    },
+    fixable: null,
+    schema: [],
+    messages: {
+      deprecated:
+        'The render helper is deprecated in favor of using components. See https://emberjs.com/deprecations/v2.x/#toc_code-render-code-helper',
+    },
+    originallyFrom: {
+      name: 'ember-template-lint',
+      rule: 'lib/rules/deprecated-render-helper.js',
+      docs: 'docs/rule/deprecated-render-helper.md',
+      tests: 'test/unit/rules/deprecated-render-helper-test.js',
+    },
+  },
+
+  create(context) {
+    function checkForRender(node) {
+      if (
+        node.path &&
+        node.path.type === 'GlimmerPathExpression' &&
+        node.path.original === 'render'
+      ) {
+        context.report({
+          node,
+          messageId: 'deprecated',
+        });
+      }
+    }
+
+    return {
+      GlimmerMustacheStatement(node) {
+        checkForRender(node);
+      },
+
+      GlimmerBlockStatement(node) {
+        checkForRender(node);
+      },
+    };
+  },
+};
diff --git a/tests/lib/rules/template-deprecated-render-helper.js b/tests/lib/rules/template-deprecated-render-helper.js
new file mode 100644
index 0000000000..8bbec129d0
--- /dev/null
+++ b/tests/lib/rules/template-deprecated-render-helper.js
@@ -0,0 +1,85 @@
+const rule = require('../../../lib/rules/template-deprecated-render-helper');
+const RuleTester = require('eslint').RuleTester;
+
+const ruleTester = new RuleTester({
+  parser: require.resolve('ember-eslint-parser'),
+  parserOptions: { ecmaVersion: 2022, sourceType: 'module' },
+});
+
+ruleTester.run('template-deprecated-render-helper', rule, {
+  valid: [
+    '<template><MyComponent /></template>',
+    '<template>{{this.render}}</template>',
+    '<template>{{valid-compoennt}}</template>',
+    '<template>{{input placeholder=(t "email") value=email}}</template>',
+    '<template>{{title "CrossCheck Web" prepent=true separator=" | "}}</template>',
+    '<template>{{hockey-player teamName="Boston Bruins"}}</template>',
+    '<template>{{false}}</template>',
+    '<template>{{"foo"}}</template>',
+    '<template>{{42}}</template>',
+    '<template>{{null}}</template>',
+    '<template>{{undefined}}</template>',
+  ],
+  invalid: [
+    {
+      code: '<template>{{render "user"}}</template>',
+      output: null,
+      errors: [{ messageId: 'deprecated' }],
+    },
+
+    {
+      code: "<template>{{render 'ken-griffey'}}</template>",
+      output: null,
+      errors: [{ messageId: 'deprecated' }],
+    },
+    {
+      code: "<template>{{render 'baseball-player' pitcher}}</template>",
+      output: null,
+      errors: [{ messageId: 'deprecated' }],
+    },
+  ],
+});
+
+const hbsRuleTester = new RuleTester({
+  parser: require.resolve('ember-eslint-parser/hbs'),
+  parserOptions: {
+    ecmaVersion: 2022,
+    sourceType: 'module',
+  },
+});
+
+hbsRuleTester.run('template-deprecated-render-helper', rule, {
+  valid: [
+    '{{valid-compoennt}}',
+    '{{input placeholder=(t "email") value=email}}',
+    '{{title "CrossCheck Web" prepent=true separator=" | "}}',
+    '{{hockey-player teamName="Boston Bruins"}}',
+    '{{false}}',
+    '{{"foo"}}',
+    '{{42}}',
+    '{{null}}',
+    '{{undefined}}',
+  ],
+  invalid: [
+    {
+      code: "{{render 'ken-griffey'}}",
+      output: null,
+      errors: [
+        {
+          message:
+            'The render helper is deprecated in favor of using components. See https://emberjs.com/deprecations/v2.x/#toc_code-render-code-helper',
+        },
+      ],
+    },
+    {
+      code: "{{render 'baseball-player' pitcher}}",
+      output: null,
+      errors: [
+        {
+          message:
+            'The render helper is deprecated in favor of using components. See https://emberjs.com/deprecations/v2.x/#toc_code-render-code-helper',
+        },
+      ],
+    },
+  ],
+});

From 38db42b9520016e0d0693ba01a9e7a20f891e0a7 Mon Sep 17 00:00:00 2001
From: NullVoxPopuli <199018+NullVoxPopuli@users.noreply.github.com>
Date: Fri, 13 Mar 2026 13:34:15 -0400
Subject: [PATCH 2/2] Update with fixer

---
 README.md                                     |  2 +-
 .../template-deprecated-render-helper.md      |  2 ++
 .../template-deprecated-render-helper.js      | 26 ++++++++++++++++++-
 .../template-deprecated-render-helper.js      | 25 +++++-------------
 4 files changed, 35 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index 2abdf640df..b695f7a52e 100644
--- a/README.md
+++ b/README.md
@@ -292,7 +292,7 @@ rules in templates can be disabled with eslint directives with mustache or html
 | [no-old-shims](docs/rules/no-old-shims.md)                                                       | disallow usage of old shims for modules                   | ✅  | 🔧 |    |
 | [no-string-prototype-extensions](docs/rules/no-string-prototype-extensions.md)                   | disallow usage of `String` prototype extensions           | ✅  |    |    |
 | [template-deprecated-inline-view-helper](docs/rules/template-deprecated-inline-view-helper.md)   | disallow inline {{view}} helper                           |    | 🔧 |    |
-| [template-deprecated-render-helper](docs/rules/template-deprecated-render-helper.md)             | disallow {{render}} helper                                |    |    |    |
+| [template-deprecated-render-helper](docs/rules/template-deprecated-render-helper.md)             | disallow {{render}} helper                                |    | 🔧 |    |
 | [template-no-action](docs/rules/template-no-action.md)                                           | disallow {{action}} helper                                |    |    |    |
 | [template-no-attrs-in-components](docs/rules/template-no-attrs-in-components.md)                 | disallow attrs in component templates                     |    |    |    |
 | [template-no-link-to-positional-params](docs/rules/template-no-link-to-positional-params.md)     | disallow positional params in LinkTo component            |    |    |    |
diff --git a/docs/rules/template-deprecated-render-helper.md b/docs/rules/template-deprecated-render-helper.md
index c0fb7dbcc8..b4ea69d017 100644
--- a/docs/rules/template-deprecated-render-helper.md
+++ b/docs/rules/template-deprecated-render-helper.md
@@ -1,5 +1,7 @@
 # ember/template-deprecated-render-helper
 
+🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
+
 > **HBS Only**: This rule applies to classic `.hbs` template files only (loose mode). It is not relevant for `gjs`/`gts` files (strict mode), where these patterns cannot occur.
 
 <!-- end auto-generated rule header -->
diff --git a/lib/rules/template-deprecated-render-helper.js b/lib/rules/template-deprecated-render-helper.js
index 6874ae80b9..2bd35690d2 100644
--- a/lib/rules/template-deprecated-render-helper.js
+++ b/lib/rules/template-deprecated-render-helper.js
@@ -8,7 +8,7 @@ module.exports = {
       url: 'https://github.com/ember-cli/eslint-plugin-ember/tree/master/docs/rules/template-deprecated-render-helper.md',
       templateMode: 'loose',
     },
-    fixable: null,
+    fixable: 'code',
     schema: [],
     messages: {
       deprecated:
@@ -23,6 +23,29 @@ module.exports = {
   },
 
   create(context) {
+    const sourceCode = context.sourceCode;
+
+    function buildFix(node) {
+      const first = node.params[0];
+      if (!first || first.type !== 'GlimmerStringLiteral') {
+        return null;
+      }
+      const templateName = first.value;
+
+      if (node.params.length === 1) {
+        // {{render 'name'}} → {{name}}
+        return (fixer) => fixer.replaceText(node, `{{${templateName}}}`);
+      }
+
+      if (node.params.length === 2) {
+        // {{render 'name' model}} → {{name model=model}}
+        const model = sourceCode.getText(node.params[1]);
+        return (fixer) => fixer.replaceText(node, `{{${templateName} model=${model}}}`);
+      }
+
+      return null;
+    }
+
     function checkForRender(node) {
       if (
         node.path &&
@@ -32,6 +55,7 @@ module.exports = {
         context.report({
           node,
           messageId: 'deprecated',
+          fix: buildFix(node),
         });
       }
     }
diff --git a/tests/lib/rules/template-deprecated-render-helper.js b/tests/lib/rules/template-deprecated-render-helper.js
index 8bbec129d0..135f63a2b3 100644
--- a/tests/lib/rules/template-deprecated-render-helper.js
+++ b/tests/lib/rules/template-deprecated-render-helper.js
@@ -23,18 +23,17 @@ ruleTester.run('template-deprecated-render-helper', rule, {
   invalid: [
     {
       code: '<template>{{render "user"}}</template>',
-      output: null,
+      output: '<template>{{user}}</template>',
       errors: [{ messageId: 'deprecated' }],
     },
-
     {
       code: "<template>{{render 'ken-griffey'}}</template>",
-      output: null,
+      output: '<template>{{ken-griffey}}</template>',
       errors: [{ messageId: 'deprecated' }],
     },
     {
       code: "<template>{{render 'baseball-player' pitcher}}</template>",
-      output: null,
+      output: '<template>{{baseball-player model=pitcher}}</template>',
       errors: [{ messageId: 'deprecated' }],
     },
   ],
@@ -63,23 +62,13 @@ hbsRuleTester.run('template-deprecated-render-helper', rule, {
   invalid: [
     {
       code: "{{render 'ken-griffey'}}",
-      output: null,
-      errors: [
-        {
-          message:
-            'The render helper is deprecated in favor of using components. See https://emberjs.com/deprecations/v2.x/#toc_code-render-code-helper',
-        },
-      ],
+      output: '{{ken-griffey}}',
+      errors: [{ messageId: 'deprecated' }],
     },
     {
       code: "{{render 'baseball-player' pitcher}}",
-      output: null,
-      errors: [
-        {
-          message:
-            'The render helper is deprecated in favor of using components. See https://emberjs.com/deprecations/v2.x/#toc_code-render-code-helper',
-        },
-      ],
+      output: '{{baseball-player model=pitcher}}',
+      errors: [{ messageId: 'deprecated' }],
     },
   ],
 });