Merge pull request #2444 from NullVoxPopuli/nvp/template-lint-extract-rule-template-no-input-placeholder

Extract rule: template-no-input-placeholder

Author: NullVoxPopuli

README.md

@@ -203,6 +203,7 @@ rules in templates can be disabled with eslint directives with mustache or html
 | [template-no-chained-this](docs/rules/template-no-chained-this.md)                                     | disallow redundant `this.this` in templates                     |    | 🔧 |    |
 | [template-no-debugger](docs/rules/template-no-debugger.md)                                             | disallow {{debugger}} in templates                              |    |    |    |
 | [template-no-element-event-actions](docs/rules/template-no-element-event-actions.md)                   | disallow element event actions (use {{on}} modifier instead)    |    |    |    |
+| [template-no-input-placeholder](docs/rules/template-no-input-placeholder.md)                           | disallow placeholder attribute on input elements                |    |    |    |
 | [template-no-input-tagname](docs/rules/template-no-input-tagname.md)                                   | disallow tagName attribute on {{input}} helper                  |    |    |    |
 | [template-no-log](docs/rules/template-no-log.md)                                                       | disallow {{log}} in templates                                   |    |    |    |
 

docs/rules/template-no-input-placeholder.md

@@ -0,0 +1,47 @@
+# ember/template-no-input-placeholder
+
+<!-- end auto-generated rule header -->
+
+Disallows `placeholder` attribute on input elements.
+
+## Rule Details
+
+The `placeholder` attribute should not be used as it has accessibility issues. Use proper labels instead.
+
+## Examples
+
+Examples of **incorrect** code for this rule:
+
+```gjs
+<template>
+  <input placeholder="Enter username" />
+</template>
+```
+
+```gjs
+<template>
+  <input type="text" placeholder="Username" />
+</template>
+```
+
+Examples of **correct** code for this rule:
+
+```gjs
+<template>
+  <label>
+    Username
+    <input type="text" />
+  </label>
+</template>
+```
+
+```gjs
+<template>
+  <input type="text" aria-label="Username" />
+</template>
+```
+
+## References
+
+- [eslint-plugin-ember template-no-input-placeholder](https://github.com/ember-cli/eslint-plugin-ember/blob/master/docs/rules/template-no-input-placeholder.md)
+- [Placeholders in Form Fields Are Harmful](https://www.nngroup.com/articles/form-design-placeholders/)

lib/rules/template-no-input-placeholder.js

@@ -0,0 +1,36 @@
+/** @type {import('eslint').Rule.RuleModule} */
+module.exports = {
+  meta: {
+    type: 'suggestion',
+    docs: {
+      description: 'disallow placeholder attribute on input elements',
+      category: 'Best Practices',
+      strictGjs: true,
+      strictGts: true,
+      url: 'https://github.com/ember-cli/eslint-plugin-ember/tree/master/docs/rules/template-no-input-placeholder.md',
+    },
+    fixable: null,
+    schema: [],
+    messages: {
+      noPlaceholder:
+        'Do not use placeholder attribute. Use a label instead for better accessibility.',
+    },
+  },
+
+  create(context) {
+    return {
+      GlimmerElementNode(node) {
+        if (node.tag === 'input' && node.attributes) {
+          for (const attr of node.attributes) {
+            if (attr.type === 'GlimmerAttrNode' && attr.name === 'placeholder') {
+              context.report({
+                node: attr,
+                messageId: 'noPlaceholder',
+              });
+            }
+          }
+        }
+      },
+    };
+  },
+};

tests/lib/rules/template-no-input-placeholder.js

@@ -0,0 +1,74 @@
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const rule = require('../../../lib/rules/template-no-input-placeholder');
+const RuleTester = require('eslint').RuleTester;
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+const ruleTester = new RuleTester({
+  parser: require.resolve('ember-eslint-parser'),
+  parserOptions: { ecmaVersion: 2022, sourceType: 'module' },
+});
+
+ruleTester.run('template-no-input-placeholder', rule, {
+  valid: [
+    `<template>
+      <label>
+        Username
+        <input type="text" />
+      </label>
+    </template>`,
+    `<template>
+      <input type="text" aria-label="Username" />
+    </template>`,
+    `<template>
+      <div></div>
+    </template>`,
+  ],
+
+  invalid: [
+    {
+      code: `<template>
+        <input placeholder="Enter username" />
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message:
+            'Do not use placeholder attribute. Use a label instead for better accessibility.',
+          type: 'GlimmerAttrNode',
+        },
+      ],
+    },
+    {
+      code: `<template>
+        <input type="text" placeholder="Username" />
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message:
+            'Do not use placeholder attribute. Use a label instead for better accessibility.',
+          type: 'GlimmerAttrNode',
+        },
+      ],
+    },
+    {
+      code: `<template>
+        <input type="email" placeholder="Email" />
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message:
+            'Do not use placeholder attribute. Use a label instead for better accessibility.',
+          type: 'GlimmerAttrNode',
+        },
+      ],
+    },
+  ],
+});