.config/coc/extensions/node_modules/coc-prettier/node_modules/eslint/lib/rules/default-case.js

   1 /**
   2  * @fileoverview require default case in switch statements
   3  * @author Aliaksei Shytkin
   4  */
   5 "use strict";
   6
   7 const DEFAULT_COMMENT_PATTERN = /^no default$/iu;
   8
   9 //------------------------------------------------------------------------------
  10 // Rule Definition
  11 //------------------------------------------------------------------------------
  12
  13 module.exports = {
  14     meta: {
  15         type: "suggestion",
  16
  17         docs: {
  18             description: "require `default` cases in `switch` statements",
  19             category: "Best Practices",
  20             recommended: false,
  21             url: "https://eslint.org/docs/rules/default-case"
  22         },
  23
  24         schema: [{
  25             type: "object",
  26             properties: {
  27                 commentPattern: {
  28                     type: "string"
  29                 }
  30             },
  31             additionalProperties: false
  32         }],
  33
  34         messages: {
  35             missingDefaultCase: "Expected a default case."
  36         }
  37     },
  38
  39     create(context) {
  40         const options = context.options[0] || {};
  41         const commentPattern = options.commentPattern
  42             ? new RegExp(options.commentPattern, "u")
  43             : DEFAULT_COMMENT_PATTERN;
  44
  45         const sourceCode = context.getSourceCode();
  46
  47         //--------------------------------------------------------------------------
  48         // Helpers
  49         //--------------------------------------------------------------------------
  50
  51         /**
  52          * Shortcut to get last element of array
  53          * @param  {*[]} collection Array
  54          * @returns {*} Last element
  55          */
  56         function last(collection) {
  57             return collection[collection.length - 1];
  58         }
  59
  60         //--------------------------------------------------------------------------
  61         // Public
  62         //--------------------------------------------------------------------------
  63
  64         return {
  65
  66             SwitchStatement(node) {
  67
  68                 if (!node.cases.length) {
  69
  70                     /*
  71                      * skip check of empty switch because there is no easy way
  72                      * to extract comments inside it now
  73                      */
  74                     return;
  75                 }
  76
  77                 const hasDefault = node.cases.some(v => v.test === null);
  78
  79                 if (!hasDefault) {
  80
  81                     let comment;
  82
  83                     const lastCase = last(node.cases);
  84                     const comments = sourceCode.getCommentsAfter(lastCase);
  85
  86                     if (comments.length) {
  87                         comment = last(comments);
  88                     }
  89
  90                     if (!comment || !commentPattern.test(comment.value.trim())) {
  91                         context.report({ node, messageId: "missingDefaultCase" });
  92                     }
  93                 }
  94             }
  95         };
  96     }
  97 };