eslint/lib/linter/config-comment-parser.js

   1 /**
   2  * @fileoverview Config Comment Parser
   3  * @author Nicholas C. Zakas
   4  */
   5
   6 /* eslint class-methods-use-this: off -- Methods desired on instance */
   7 "use strict";
   8
   9 //------------------------------------------------------------------------------
  10 // Requirements
  11 //------------------------------------------------------------------------------
  12
  13 const levn = require("levn"),
  14     {
  15         Legacy: {
  16             ConfigOps
  17         }
  18     } = require("@eslint/eslintrc/universal");
  19
  20 const debug = require("debug")("eslint:config-comment-parser");
  21
  22 //------------------------------------------------------------------------------
  23 // Public Interface
  24 //------------------------------------------------------------------------------
  25
  26 /**
  27  * Object to parse ESLint configuration comments inside JavaScript files.
  28  * @name ConfigCommentParser
  29  */
  30 module.exports = class ConfigCommentParser {
  31
  32     /**
  33      * Parses a list of "name:string_value" or/and "name" options divided by comma or
  34      * whitespace. Used for "global" and "exported" comments.
  35      * @param {string} string The string to parse.
  36      * @param {Comment} comment The comment node which has the string.
  37      * @returns {Object} Result map object of names and string values, or null values if no value was provided
  38      */
  39     parseStringConfig(string, comment) {
  40         debug("Parsing String config");
  41
  42         const items = {};
  43
  44         // Collapse whitespace around `:` and `,` to make parsing easier
  45         const trimmedString = string.replace(/\s*([:,])\s*/gu, "$1");
  46
  47         trimmedString.split(/\s|,+/u).forEach(name => {
  48             if (!name) {
  49                 return;
  50             }
  51
  52             // value defaults to null (if not provided), e.g: "foo" => ["foo", null]
  53             const [key, value = null] = name.split(":");
  54
  55             items[key] = { value, comment };
  56         });
  57         return items;
  58     }
  59
  60     /**
  61      * Parses a JSON-like config.
  62      * @param {string} string The string to parse.
  63      * @param {Object} location Start line and column of comments for potential error message.
  64      * @returns {({success: true, config: Object}|{success: false, error: Problem})} Result map object
  65      */
  66     parseJsonConfig(string, location) {
  67         debug("Parsing JSON config");
  68
  69         let items = {};
  70
  71         // Parses a JSON-like comment by the same way as parsing CLI option.
  72         try {
  73             items = levn.parse("Object", string) || {};
  74
  75             // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
  76             // Also, commaless notations have invalid severity:
  77             //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
  78             // Should ignore that case as well.
  79             if (ConfigOps.isEverySeverityValid(items)) {
  80                 return {
  81                     success: true,
  82                     config: items
  83                 };
  84             }
  85         } catch {
  86
  87             debug("Levn parsing failed; falling back to manual parsing.");
  88
  89             // ignore to parse the string by a fallback.
  90         }
  91
  92         /*
  93          * Optionator cannot parse commaless notations.
  94          * But we are supporting that. So this is a fallback for that.
  95          */
  96         items = {};
  97         const normalizedString = string.replace(/([-a-zA-Z0-9/]+):/gu, "\"$1\":").replace(/(\]|[0-9])\s+(?=")/u, "$1,");
  98
  99         try {
 100             items = JSON.parse(`{${normalizedString}}`);
 101         } catch (ex) {
 102             debug("Manual parsing failed.");
 103
 104             return {
 105                 success: false,
 106                 error: {
 107                     ruleId: null,
 108                     fatal: true,
 109                     severity: 2,
 110                     message: `Failed to parse JSON from '${normalizedString}': ${ex.message}`,
 111                     line: location.start.line,
 112                     column: location.start.column + 1
 113                 }
 114             };
 115
 116         }
 117
 118         return {
 119             success: true,
 120             config: items
 121         };
 122     }
 123
 124     /**
 125      * Parses a config of values separated by comma.
 126      * @param {string} string The string to parse.
 127      * @returns {Object} Result map of values and true values
 128      */
 129     parseListConfig(string) {
 130         debug("Parsing list config");
 131
 132         const items = {};
 133
 134         // Collapse whitespace around commas
 135         string.replace(/\s*,\s*/gu, ",").split(/,+/u).forEach(name => {
 136             const trimmedName = name.trim();
 137
 138             if (trimmedName) {
 139                 items[trimmedName] = true;
 140             }
 141         });
 142         return items;
 143     }
 144
 145 };