Issue 7321 - Lower-case non-literal patterns for case-insensitive matching

lib/filterClasses.js

Index: lib/filterClasses.js
===================================================================
--- a/lib/filterClasses.js
+++ b/lib/filterClasses.js
@@ -719,37 +719,36 @@
     this.thirdParty = thirdParty;
   if (sitekeys != null)
     this.sitekeySource = sitekeys;
   if (rewrite != null)
     this.rewrite = rewrite;
   if (resourceName)
     this.resourceName = resourceName;
 
+  if (!this.matchCase)
+    regexpSource = regexpSource.toLowerCase();
+
   if (regexpSource.length >= 2 &&
       regexpSource[0] == "/" &&
       regexpSource[regexpSource.length - 1] == "/")
   {
     // The filter is a regular expression - convert it immediately to
     // catch syntax errors
-    let regexp = new RegExp(regexpSource.substring(1, regexpSource.length - 1),
-                            this.matchCase ? "" : "i");
+    let regexp = new RegExp(regexpSource.substring(1, regexpSource.length - 1));
     Object.defineProperty(this, "regexp", {value: regexp});
   }
   else
   {
     // Patterns like /foo/bar/* exist so that they are not treated as regular
     // expressions. We drop any superfluous wildcards here so our optimizations
     // can kick in.
     if (this.rewrite == null || this.resourceName)
       regexpSource = regexpSource.replace(/^\*+/, "").replace(/\*+$/, "");
 
-    if (!this.matchCase && isLiteralPattern(regexpSource))
-      regexpSource = regexpSource.toLowerCase();
-
     // No need to convert this filter to regular expression yet, do it on demand
     this.pattern = regexpSource;
   }
 }
 exports.RegExpFilter = RegExpFilter;
 
 RegExpFilter.prototype = extend(ActiveFilter, {
   /**
@@ -776,20 +775,17 @@
    * @type {RegExp}
    */
   get regexp()
   {
     let value = null;
 
     let {pattern, rewrite, resourceName} = this;
     if ((rewrite != null && !resourceName) || !isLiteralPattern(pattern))
-    {
-      value = new RegExp(filterToRegExp(pattern, rewrite != null),
-                         this.matchCase ? "" : "i");
-    }
+      value = new RegExp(filterToRegExp(pattern, rewrite != null));
 
     Object.defineProperty(this, "regexp", {value});
     return value;
   },
   /**
    * Content types the filter applies to, combination of values from
    * RegExpFilter.typeMap
    * @type {number}
@@ -893,24 +889,24 @@
    * @param {string} location The URL to check.
    * @param {?string} [lowerCaseLocation] The lower-case version of the URL to
    *   check, for case-insensitive matching.
    * @returns {boolean} <code>true</code> if the URL matches.
    * @package
    */
   matchesLocation(location, lowerCaseLocation)
   {
+    if (!this.matchCase)
+      location = lowerCaseLocation || location.toLowerCase();
+
     let {regexp} = this;
 
     if (regexp)
       return regexp.test(location);
 
-    if (!this.matchCase)
-      location = lowerCaseLocation || location.toLowerCase();
-
     let {pattern} = this;
 
     let startsWithDoubleAnchor = pattern[0] == "|" && pattern[1] == "|";
     let endsWithSeparator = pattern[pattern.length - 1] == "^";
 
     if (startsWithDoubleAnchor)
       pattern = pattern.substr(2);