feat: Add named-functions rule to recommended and recommended-typescript configs

Author: tomerh2001

README.md

@@ -20,6 +20,7 @@ This repository contains custom ESLint rules to enhance code quality and consist
 
 | Name                                                 | Description                                                                      | 💼                                  | 🔧 |
 | :--------------------------------------------------- | :------------------------------------------------------------------------------- | :---------------------------------- | :- |
+| [named-functions](docs/rules/named-functions.md)     | Enforce top-level functions to be named functions                                | ✅ ![badge-recommended-typescript][] | 🔧 |
 | [no-comments](docs/rules/no-comments.md)             | Disallow comments except for specified allowed patterns.                         | ✅ ![badge-recommended-typescript][] | 🔧 |
 | [no-default-export](docs/rules/no-default-export.md) | Convert unnamed default exports to named default exports based on the file name. | ✅ ![badge-recommended-typescript][] | 🔧 |
 | [no-destructuring](docs/rules/no-destructuring.md)   | Disallow destructuring that does not meet certain conditions                     | ✅ ![badge-recommended-typescript][] |    |

docs/rules/named-functions.md

@@ -0,0 +1,7 @@
+# Enforce top-level functions to be named functions (`th-rules/named-functions`)
+
+💼 This rule is enabled in the following configs: ✅ `recommended`, `recommended-typescript`.
+
+🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
+
+<!-- end auto-generated rule header -->

src/index.js

@@ -19,6 +19,7 @@ configs.recommended = {
 		'th-rules/no-destructuring': 'error',
 		'th-rules/no-default-export': 'error',
 		'th-rules/no-comments': 'error',
+		'th-rules/named-functions': 'error',
 		'unicorn/prefer-module': 'warn',
 		'unicorn/filename-case': 'off',
 		'unicorn/no-array-callback-reference': 'off',

src/rules/named-functions.js

@@ -0,0 +1,80 @@
+module.exports = {
+  meta: {
+    type: 'problem',
+    docs: {
+      description: 'Enforce top-level functions to be named functions',
+      url: 'https://github.com/tomerh2001/eslint-plugin-th-rules/blob/main/docs/rules/named-functions.md',
+    },
+    fixable: 'code',
+    schema: [],
+  },
+
+  create(context) {
+    function reportAndFix(node, name) {
+      context.report({
+        node,
+        message: 'Top-level functions must be named function declarations.',
+        fix(fixer) {
+          if (node.type === 'FunctionExpression' && node.parent.type === 'VariableDeclarator') {
+            // Convert to a function declaration
+            const sourceCode = context.getSourceCode();
+            const varName = node.parent.id.name;
+            const functionBody = sourceCode.getText(node.body);
+            const functionParams = sourceCode.getText(node.params);
+            const asyncKeyword = node.async ? 'async ' : '';
+            const generatorKeyword = node.generator ? '*' : '';
+
+            const functionDeclaration = `${asyncKeyword}function ${generatorKeyword}${varName}(${functionParams}) ${functionBody}`;
+            return fixer.replaceText(node.parent.parent, functionDeclaration);
+          }
+
+          if (node.type === 'FunctionExpression') {
+            // Convert to a function declaration
+            const sourceCode = context.getSourceCode();
+            const functionBody = sourceCode.getText(node.body);
+            const functionParams = sourceCode.getText(node.params);
+            const asyncKeyword = node.async ? 'async ' : '';
+            const generatorKeyword = node.generator ? '*' : '';
+
+            const functionDeclaration = `${asyncKeyword}function ${generatorKeyword}${name}(${functionParams}) ${functionBody}`;
+            return fixer.replaceText(node, functionDeclaration);
+          }
+
+          return null;
+        },
+      });
+    }
+
+    return {
+      Program(programNode) {
+        const topLevelNodes = programNode.body;
+
+        topLevelNodes.forEach((node) => {
+          if (node.type === 'FunctionDeclaration') {
+            // Skip if already a named function declaration
+            return;
+          }
+
+          if (
+            node.type === 'FunctionExpression' ||
+            (node.type === 'VariableDeclaration' && node.declarations[0].init?.type === 'FunctionExpression')
+          ) {
+            // Force it to be a named function declaration
+            if (node.type === 'VariableDeclaration') {
+              const varName = node.declarations[0].id.name;
+              reportAndFix(node.declarations[0].init, varName);
+            } else {
+              reportAndFix(node, 'Anonymous');
+            }
+          }
+
+          if (node.type === 'ExpressionStatement' && node.expression.type === 'ArrowFunctionExpression') {
+            // Convert arrow functions into named function declarations
+            const varName = node.expression.id ? node.expression.id.name : 'Anonymous';
+            reportAndFix(node.expression, varName);
+          }
+        });
+      },
+    };
+  },
+};