Issue 4864 - Start using ESLint for adblockpluschrome

lib/filterValidation.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 11 matching lines @@
 const {Filter, InvalidFilter, ElemHideBase} = require("filterClasses");
 const {Utils} = require("utils");
 
 /**
  * An error returned by
  * {@link module:filterValidation.parseFilter parseFilter()} or
  * {@link module:filterValidation.parseFilters parseFilters()}
  * indicating that a given filter cannot be parsed,
  * contains an invalid CSS selector or is a filter list header.
  *
+ * @param {string} type See documentation in the constructor below.
+ * @param {Object} [details] Contains the "reason" and / or "selector"
+ *                           properties.
  * @constructor
  */
 function FilterParsingError(type, details)
 {
   /**
    * Indicates why the filter is rejected. Possible choices:
    * "invalid-filter", "invalid-css-selector", "unexpected-filter-list-header"
    *
    * @type {string}
    */
@@ skipping 22 matching lines @@
    * Returns a detailed translated error message.
    *
    * @return {string}
    */
   toString()
   {
     let message;
     if (this.reason)
       message = Utils.getString(this.reason);
     else
+    {
       message = ext.i18n.getMessage(
         this.type.replace(/-/g, "_"),
         "selector" in this ? "'" + this.selector + "'" : null
       );
+    }
 
     if (this.lineno)
-      message = ext.i18n.getMessage("line", this.lineno.toLocaleString()) + ": " + message;
-
+    {
+      message = ext.i18n.getMessage(
+        "line", this.lineno.toLocaleString()
+      ) + ": " + message;
+    }
     return message;
   }
 };
 
 function isValidCSSSelector(selector)
 {
   let style = document.createElement("style");
   document.documentElement.appendChild(style);
-  let sheet = style.sheet;
+  let {sheet} = style;
   document.documentElement.removeChild(style);
 
   try
   {
     document.querySelector(selector);
     sheet.insertRule(selector + "{}", 0);
   }
   catch (e)
   {
     return false;
   }
   return true;
 }
 
 /**
  * @typedef ParsedFilter
- * @property {?Filter} [filter]  The parsed filter if it is valid.
- *                               Or null if the given string is empty.
- * @property {FilterParsingError} [error]  See {@link module:filterValidation~FilterParsingError FilterParsingError}
- *
+ * @property {?Filter} [filter]
+ *   The parsed filter if it is valid. Or null if the given string is empty.
+ * @property {FilterParsingError} [error]
+ *   See {@link module:filterValidation~FilterParsingError FilterParsingError}
  */
 
 let parseFilter =
 /**
  * Parses and validates a filter given by the user.
  *
  * @param {string}  text
  * @return {ParsedFilter}
  */
 exports.parseFilter = text =>
 {
   let filter = null;
   text = Filter.normalize(text);
 
   if (text)
   {
     if (text[0] == "[")
       return {error: new FilterParsingError("unexpected-filter-list-header")};
 
     filter = Filter.fromText(text);
 
     if (filter instanceof InvalidFilter)
-      return {error: new FilterParsingError("invalid-filter", {reason: filter.reason})};
-
+    {
+      return {error: new FilterParsingError("invalid-filter",
+                                            {reason: filter.reason})};
+    }
     if (filter instanceof ElemHideBase && !isValidCSSSelector(filter.selector))
-      return {error: new FilterParsingError("invalid-css-selector", {selector: filter.selector})};
+    {
+      return {error: new FilterParsingError("invalid-css-selector",
+                                            {selector: filter.selector})};
+    }
   }
 
-  return {filter: filter};
+  return {filter};
 };
 
 /**
  * @typedef ParsedFilters
- * @property {Filter[]} filters  The parsed result without invalid filters.
- * @property {FilterParsingError[]} errors  See {@link module:filterValidation~FilterParsingError FilterParsingError}
+ * @property {Filter[]} filters
+ *   The parsed result without invalid filters.
+ * @property {FilterParsingError[]} errors
+ *   See {@link module:filterValidation~FilterParsingError FilterParsingError}
  */
 
 /**
  * Parses and validates a newline-separated list of filters given by the user.
  *
  * @param {string}  text
  * @return {ParsedFilters}
  */
 exports.parseFilters = text =>
 {
   let lines = text.split("\n");
   let filters = [];
   let errors = [];
 
   for (let i = 0; i < lines.length; i++)
   {
     let {filter, error} = parseFilter(lines[i]);
 
     if (filter)
       filters.push(filter);
 
     if (error)
     {
       error.lineno = i + 1;
       errors.push(error);
     }
   }
 
-  return {filters: filters, errors: errors};
+  return {filters, errors};
 };