| /** |
| * @fileoverview require default case in switch statements |
| * @author Aliaksei Shytkin |
| */ |
| "use strict"; |
| |
| const DEFAULT_COMMENT_PATTERN = /^no default$/iu; |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| type: "suggestion", |
| |
| docs: { |
| description: "require `default` cases in `switch` statements", |
| category: "Best Practices", |
| recommended: false, |
| url: "https://eslint.org/docs/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.getSourceCode(); |
| |
| //-------------------------------------------------------------------------- |
| // Helpers |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * Shortcut to get last element of array |
| * @param {*[]} collection Array |
| * @returns {*} 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" }); |
| } |
| } |
| } |
| }; |
| } |
| }; |