eslint/lib/rules/symbol-description.js

   1 /**
   2  * @fileoverview Rule to enforce description with the `Symbol` object
   3  * @author Jarek Rencz
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const astUtils = require("./utils/ast-utils");
  13
  14 //------------------------------------------------------------------------------
  15 // Rule Definition
  16 //------------------------------------------------------------------------------
  17
  18
  19 module.exports = {
  20     meta: {
  21         type: "suggestion",
  22
  23         docs: {
  24             description: "require symbol descriptions",
  25             recommended: false,
  26             url: "https://eslint.org/docs/rules/symbol-description"
  27         },
  28         fixable: null,
  29         schema: [],
  30         messages: {
  31             expected: "Expected Symbol to have a description."
  32         }
  33     },
  34
  35     create(context) {
  36
  37         /**
  38          * Reports if node does not conform the rule in case rule is set to
  39          * report missing description
  40          * @param {ASTNode} node A CallExpression node to check.
  41          * @returns {void}
  42          */
  43         function checkArgument(node) {
  44             if (node.arguments.length === 0) {
  45                 context.report({
  46                     node,
  47                     messageId: "expected"
  48                 });
  49             }
  50         }
  51
  52         return {
  53             "Program:exit"() {
  54                 const scope = context.getScope();
  55                 const variable = astUtils.getVariableByName(scope, "Symbol");
  56
  57                 if (variable && variable.defs.length === 0) {
  58                     variable.references.forEach(reference => {
  59                         const node = reference.identifier;
  60
  61                         if (astUtils.isCallee(node)) {
  62                             checkArgument(node.parent);
  63                         }
  64                     });
  65                 }
  66             }
  67         };
  68
  69     }
  70 };