eslint/lib/rules/require-unicode-regexp.js

   1 /**
   2  * @fileoverview Rule to enforce the use of `u` flag on RegExp.
   3  * @author Toru Nagashima
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const {
  13     CALL,
  14     CONSTRUCT,
  15     ReferenceTracker,
  16     getStringIfConstant
  17 } = require("eslint-utils");
  18
  19 //------------------------------------------------------------------------------
  20 // Rule Definition
  21 //------------------------------------------------------------------------------
  22
  23 /** @type {import('../shared/types').Rule} */
  24 module.exports = {
  25     meta: {
  26         type: "suggestion",
  27
  28         docs: {
  29             description: "enforce the use of `u` flag on RegExp",
  30             recommended: false,
  31             url: "https://eslint.org/docs/rules/require-unicode-regexp"
  32         },
  33
  34         messages: {
  35             requireUFlag: "Use the 'u' flag."
  36         },
  37
  38         schema: []
  39     },
  40
  41     create(context) {
  42         return {
  43             "Literal[regex]"(node) {
  44                 const flags = node.regex.flags || "";
  45
  46                 if (!flags.includes("u")) {
  47                     context.report({ node, messageId: "requireUFlag" });
  48                 }
  49             },
  50
  51             Program() {
  52                 const scope = context.getScope();
  53                 const tracker = new ReferenceTracker(scope);
  54                 const trackMap = {
  55                     RegExp: { [CALL]: true, [CONSTRUCT]: true }
  56                 };
  57
  58                 for (const { node } of tracker.iterateGlobalReferences(trackMap)) {
  59                     const flagsNode = node.arguments[1];
  60                     const flags = getStringIfConstant(flagsNode, scope);
  61
  62                     if (!flagsNode || (typeof flags === "string" && !flags.includes("u"))) {
  63                         context.report({ node, messageId: "requireUFlag" });
  64                     }
  65                 }
  66             }
  67         };
  68     }
  69 };