Extract rule: template-no-bare-yield

Author: NullVoxPopuli

README.md

@@ -189,14 +189,15 @@ rules in templates can be disabled with eslint directives with mustache or html
 
 ### Best Practices
 
-| Name                                                                                             | Description                                               | 💼 | 🔧 | 💡 |
-| :----------------------------------------------------------------------------------------------- | :-------------------------------------------------------- | :- | :- | :- |
-| [template-builtin-component-arguments](docs/rules/template-builtin-component-arguments.md)       | disallow setting certain attributes on builtin components |    |    |    |
-| [template-no-action-modifiers](docs/rules/template-no-action-modifiers.md)                       | disallow usage of {{action}} modifiers                    |    |    |    |
-| [template-no-arguments-for-html-elements](docs/rules/template-no-arguments-for-html-elements.md) | disallow @arguments on HTML elements                      |    |    |    |
-| [template-no-array-prototype-extensions](docs/rules/template-no-array-prototype-extensions.md)   | disallow usage of Ember Array prototype extensions        |    |    |    |
-| [template-no-debugger](docs/rules/template-no-debugger.md)                                       | disallow {{debugger}} in templates                        |    |    |    |
-| [template-no-log](docs/rules/template-no-log.md)                                                 | disallow {{log}} in templates                             |    |    |    |
+| Name                                                                                             | Description                                                            | 💼 | 🔧 | 💡 |
+| :----------------------------------------------------------------------------------------------- | :--------------------------------------------------------------------- | :- | :- | :- |
+| [template-builtin-component-arguments](docs/rules/template-builtin-component-arguments.md)       | disallow setting certain attributes on builtin components              |    |    |    |
+| [template-no-action-modifiers](docs/rules/template-no-action-modifiers.md)                       | disallow usage of {{action}} modifiers                                 |    |    |    |
+| [template-no-arguments-for-html-elements](docs/rules/template-no-arguments-for-html-elements.md) | disallow @arguments on HTML elements                                   |    |    |    |
+| [template-no-array-prototype-extensions](docs/rules/template-no-array-prototype-extensions.md)   | disallow usage of Ember Array prototype extensions                     |    |    |    |
+| [template-no-bare-yield](docs/rules/template-no-bare-yield.md)                                   | disallow {{yield}} without parameters outside of contextual components |    |    |    |
+| [template-no-debugger](docs/rules/template-no-debugger.md)                                       | disallow {{debugger}} in templates                                     |    |    |    |
+| [template-no-log](docs/rules/template-no-log.md)                                                 | disallow {{log}} in templates                                          |    |    |    |
 
 ### Components
 

docs/rules/template-no-bare-yield.md

@@ -0,0 +1,31 @@
+# ember/template-no-bare-yield
+
+<!-- end auto-generated rule header -->
+
+Disallow `{{yield}}` without parameters outside of contextual components.
+
+## Rule Details
+
+This rule enforces passing parameters to `{{yield}}` to make component APIs more explicit.
+
+## Examples
+
+Examples of **incorrect** code for this rule:
+
+```gjs
+<template>
+  {{yield}}
+</template>
+```
+
+Examples of **correct** code for this rule:
+
+```gjs
+<template>
+  {{yield this}}
+</template>
+
+<template>
+  {{yield @model}}
+</template>
+```

lib/rules/template-no-bare-yield.js

@@ -0,0 +1,32 @@
+/** @type {import('eslint').Rule.RuleModule} */
+module.exports = {
+  meta: {
+    type: 'problem',
+    docs: {
+      description: 'disallow {{yield}} without parameters outside of contextual components',
+      category: 'Best Practices',
+      url: 'https://github.com/ember-cli/eslint-plugin-ember/tree/master/docs/rules/template-no-bare-yield.md',
+      strictGjs: true,
+      strictGts: true,
+    },
+    schema: [],
+    messages: {
+      noBareYield: 'yield should have parameters or be used in contextual components only.',
+    },
+  },
+
+  create(context) {
+    return {
+      GlimmerMustacheStatement(node) {
+        if (node.path.type === 'GlimmerPathExpression' && node.path.original === 'yield') {
+          if (!node.params || node.params.length === 0) {
+            context.report({
+              node,
+              messageId: 'noBareYield',
+            });
+          }
+        }
+      },
+    };
+  },
+};

tests/lib/rules/template-no-bare-yield.js

@@ -0,0 +1,36 @@
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const rule = require('../../../lib/rules/template-no-bare-yield');
+const RuleTester = require('eslint').RuleTester;
+
+const ruleTester = new RuleTester({
+  parser: require.resolve('ember-eslint-parser'),
+  parserOptions: { ecmaVersion: 2022, sourceType: 'module' },
+});
+
+ruleTester.run('template-no-bare-yield', rule, {
+  valid: [
+    // yield with params inside a class
+    `import Component from '@glimmer/component';
+     class MyComponent extends Component {
+       <template>{{yield this}}</template>
+     }`,
+    // yield with params inside a function
+    `function myComponent() {
+       return <template>{{yield this}}</template>;
+     }`,
+    '<template>{{yield @model}}</template>',
+    '<template><div>Content</div></template>',
+    // yield this at module level is allowed by this rule (template-no-unavailable-this handles the `this` part)
+    '<template>{{yield this}}</template>',
+  ],
+  invalid: [
+    {
+      code: '<template>{{yield}}</template>',
+      output: null,
+      errors: [{ messageId: 'noBareYield' }],
+    },
+  ],
+});