| /** | |
|  * @fileoverview Rule to flag references to undeclared variables. | |
|  * @author Mark Macdonald | |
|  */ | |
| "use strict"; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Helpers | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** | |
|  * Checks if the given node is the argument of a typeof operator. | |
|  * @param {ASTNode} node The AST node being checked. | |
|  * @returns {boolean} Whether or not the node is the argument of a typeof operator. | |
|  */ | |
| function hasTypeOfOperator(node) { | |
|     const parent = node.parent; | |
| 
 | |
|     return parent.type === "UnaryExpression" && parent.operator === "typeof"; | |
| } | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Rule Definition | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** @type {import('../shared/types').Rule} */ | |
| module.exports = { | |
|     meta: { | |
|         type: "problem", | |
| 
 | |
|         docs: { | |
|             description: "Disallow the use of undeclared variables unless mentioned in `/*global */` comments", | |
|             recommended: true, | |
|             url: "https://eslint.org/docs/latest/rules/no-undef" | |
|         }, | |
| 
 | |
|         schema: [ | |
|             { | |
|                 type: "object", | |
|                 properties: { | |
|                     typeof: { | |
|                         type: "boolean", | |
|                         default: false | |
|                     } | |
|                 }, | |
|                 additionalProperties: false | |
|             } | |
|         ], | |
|         messages: { | |
|             undef: "'{{name}}' is not defined." | |
|         } | |
|     }, | |
| 
 | |
|     create(context) { | |
|         const options = context.options[0]; | |
|         const considerTypeOf = options && options.typeof === true || false; | |
|         const sourceCode = context.sourceCode; | |
| 
 | |
|         return { | |
|             "Program:exit"(node) { | |
|                 const globalScope = sourceCode.getScope(node); | |
| 
 | |
|                 globalScope.through.forEach(ref => { | |
|                     const identifier = ref.identifier; | |
| 
 | |
|                     if (!considerTypeOf && hasTypeOfOperator(identifier)) { | |
|                         return; | |
|                     } | |
| 
 | |
|                     context.report({ | |
|                         node: identifier, | |
|                         messageId: "undef", | |
|                         data: identifier | |
|                     }); | |
|                 }); | |
|             } | |
|         }; | |
|     } | |
| };
 |