| /** | |
|  * @fileoverview require default case in switch statements | |
|  * @author Aliaksei Shytkin | |
|  */ | |
| "use strict"; | |
| 
 | |
| const DEFAULT_COMMENT_PATTERN = /^no default$/iu; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Rule Definition | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** @type {import('../shared/types').Rule} */ | |
| module.exports = { | |
|     meta: { | |
|         type: "suggestion", | |
| 
 | |
|         docs: { | |
|             description: "Require `default` cases in `switch` statements", | |
|             recommended: false, | |
|             url: "https://eslint.org/docs/latest/rules/default-case" | |
|         }, | |
| 
 | |
|         schema: [{ | |
|             type: "object", | |
|             properties: { | |
|                 commentPattern: { | |
|                     type: "string" | |
|                 } | |
|             }, | |
|             additionalProperties: false | |
|         }], | |
| 
 | |
|         messages: { | |
|             missingDefaultCase: "Expected a default case." | |
|         } | |
|     }, | |
| 
 | |
|     create(context) { | |
|         const options = context.options[0] || {}; | |
|         const commentPattern = options.commentPattern | |
|             ? new RegExp(options.commentPattern, "u") | |
|             : DEFAULT_COMMENT_PATTERN; | |
| 
 | |
|         const sourceCode = context.sourceCode; | |
| 
 | |
|         //-------------------------------------------------------------------------- | |
|         // Helpers | |
|         //-------------------------------------------------------------------------- | |
|  | |
|         /** | |
|          * Shortcut to get last element of array | |
|          * @param {*[]} collection Array | |
|          * @returns {any} Last element | |
|          */ | |
|         function last(collection) { | |
|             return collection[collection.length - 1]; | |
|         } | |
| 
 | |
|         //-------------------------------------------------------------------------- | |
|         // Public | |
|         //-------------------------------------------------------------------------- | |
|  | |
|         return { | |
| 
 | |
|             SwitchStatement(node) { | |
| 
 | |
|                 if (!node.cases.length) { | |
| 
 | |
|                     /* | |
|                      * skip check of empty switch because there is no easy way | |
|                      * to extract comments inside it now | |
|                      */ | |
|                     return; | |
|                 } | |
| 
 | |
|                 const hasDefault = node.cases.some(v => v.test === null); | |
| 
 | |
|                 if (!hasDefault) { | |
| 
 | |
|                     let comment; | |
| 
 | |
|                     const lastCase = last(node.cases); | |
|                     const comments = sourceCode.getCommentsAfter(lastCase); | |
| 
 | |
|                     if (comments.length) { | |
|                         comment = last(comments); | |
|                     } | |
| 
 | |
|                     if (!comment || !commentPattern.test(comment.value.trim())) { | |
|                         context.report({ node, messageId: "missingDefaultCase" }); | |
|                     } | |
|                 } | |
|             } | |
|         }; | |
|     } | |
| };
 |