Merge pull request #2381 from ember-cli/copilot/split-lint-rule-example

Port template-no-log rule from PR #2371

Author: NullVoxPopuli

README.md

@@ -174,6 +174,12 @@ rules in templates can be disabled with eslint directives with mustache or html
 🔧 Automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/user-guide/command-line-interface#--fix).\
 💡 Manually fixable by [editor suggestions](https://eslint.org/docs/latest/use/core-concepts#rule-suggestions).
 
+### Best Practices
+
+| Name                                             | Description                   | 💼 | 🔧 | 💡 |
+| :----------------------------------------------- | :---------------------------- | :- | :- | :- |
+| [template-no-log](docs/rules/template-no-log.md) | disallow {{log}} in templates |    |    |    |
+
 ### Components
 
 | Name                                                                       | Description                                                                                                                          | 💼 | 🔧 | 💡 |

docs/rules/template-no-log.md

@@ -0,0 +1,58 @@
+# ember/template-no-log
+
+<!-- end auto-generated rule header -->
+
+Disallows usage of `{{log}}` in templates.
+
+The `{{log}}` helper is useful for debugging but should not be present in production code. Use proper logging libraries or console statements in JavaScript code instead.
+
+## Rule Details
+
+This rule disallows the use of `{{log}}` statements in templates.
+
+## Examples
+
+Examples of **incorrect** code for this rule:
+
+```gjs
+<template>
+  {{log "debug message"}}
+  <div>Content</div>
+</template>
+```
+
+```gjs
+<template>
+  {{#if condition}}
+    {{log this.value}}
+  {{/if}}
+</template>
+```
+
+Examples of **correct** code for this rule:
+
+```gjs
+<template>
+  <div>Content</div>
+</template>
+```
+
+```gjs
+<template>
+  {{this.log}}
+</template>
+```
+
+```gjs
+<template>
+  {{logger "info"}}
+</template>
+```
+
+## Related Rules
+
+- [no-console](https://eslint.org/docs/rules/no-console) from ESLint
+
+## References
+
+- [ember-template-lint no-log](https://github.com/ember-template-lint/ember-template-lint/blob/master/docs/rule/no-log.md)

lib/rules/template-no-log.js

@@ -0,0 +1,37 @@
+/** @type {import('eslint').Rule.RuleModule} */
+module.exports = {
+  meta: {
+    type: 'problem',
+    docs: {
+      description: 'disallow {{log}} in templates',
+      category: 'Best Practices',
+      url: 'https://github.com/ember-cli/eslint-plugin-ember/tree/master/docs/rules/template-no-log.md',
+    },
+    fixable: null,
+    schema: [],
+    messages: {
+      unexpected: 'Unexpected log statement in template.',
+    },
+  },
+
+  create(context) {
+    function checkForLog(node) {
+      if (node.path && node.path.type === 'GlimmerPathExpression' && node.path.original === 'log') {
+        context.report({
+          node,
+          messageId: 'unexpected',
+        });
+      }
+    }
+
+    return {
+      GlimmerMustacheStatement(node) {
+        checkForLog(node);
+      },
+
+      GlimmerBlockStatement(node) {
+        checkForLog(node);
+      },
+    };
+  },
+};

scripts/update-rules.js

@@ -42,7 +42,8 @@ function generate(filename, filter) {
  * In order to update its content based on rules'
  * definitions, execute "npm run update"
  */
-module.exports = ${JSON.stringify(recommendedRules, null, 2)}`;
+module.exports = ${JSON.stringify(recommendedRules, null, 2)};
+`;
 
   fs.writeFileSync(recommendedRulesFile, recommendedRulesContent);
 }

tests/lib/rules/template-no-log.js

@@ -0,0 +1,75 @@
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const rule = require('../../../lib/rules/template-no-log');
+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-log', rule, {
+  valid: [
+    `<template>
+      <div>Hello World</div>
+    </template>`,
+    `<template>
+      {{this.log}}
+    </template>`,
+    `<template>
+      {{logger}}
+    </template>`,
+    `<template>
+      <div data-test-log={{true}}></div>
+    </template>`,
+  ],
+
+  invalid: [
+    {
+      code: `<template>
+        {{log "debug message"}}
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message: 'Unexpected log statement in template.',
+          type: 'GlimmerMustacheStatement',
+        },
+      ],
+    },
+    {
+      code: `<template>
+        {{#if condition}}
+          {{log this.value}}
+        {{/if}}
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message: 'Unexpected log statement in template.',
+          type: 'GlimmerMustacheStatement',
+        },
+      ],
+    },
+    {
+      code: `<template>
+        {{#log "test"}}
+          content
+        {{/log}}
+      </template>`,
+      output: null,
+      errors: [
+        {
+          message: 'Unexpected log statement in template.',
+          type: 'GlimmerBlockStatement',
+        },
+      ],
+    },
+  ],
+});