Issue 6733 - Allow empty values in filter options

test/filterClasses.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 465 matching lines @@
       "text=" + normalized,
       "csp=c s p",
       "domains=domain.com|foo.com",
       "sitekeys=FOO",
       "regexp=b\\$la",
       "contentType=" + t.CSP
     ]
   );
 
   // Some $csp edge cases
+  test.equal(Filter.normalize("$csp=  "),

[Manish Jethani, 2018/06/25 13:13:44]

This is important now because we want to return InvalidFilter on blank value for
$csp.

+             "$csp=");
   test.equal(Filter.normalize("$csp= c s p"),
              "$csp=c s p");
   test.equal(Filter.normalize("$$csp= c s p"),
              "$$csp=c s p");
   test.equal(Filter.normalize("$$$csp= c s p"),
              "$$$csp=c s p");
   test.equal(Filter.normalize("foo?csp=b a r$csp=script-src  'self'"),
              "foo?csp=bar$csp=script-src 'self'");
   test.equal(Filter.normalize("foo$bar=c s p = ba z,cs p = script-src  'self'"),
              "foo$bar=csp=baz,csp=script-src 'self'");
@@ skipping 53 matching lines @@
   // Example from https://github.com/uBlockOrigin/uBlock-issues/issues/46#issuecomment-391190533
   // The rewrite shouldn't happen.
   let rewriteEvil = "/(^https?:\\/\\/[^/])/$script,rewrite=$1.evil.com";
   let filterEvil = Filter.fromText(rewriteEvil);
 
   test.equal(
     filterEvil.rewriteUrl("https://www.adblockplus.org/script.js"),
     "https://www.adblockplus.org/script.js"
   );
 
+  // Strip.
+  let rewriteStrip = "tag$rewrite=";
+  let filterStrip = Filter.fromText(rewriteStrip);
+
+  test.equal(filterStrip.rewrite, "");
+  test.equal(
+    filterStrip.rewriteUrl("http://example.com/?tag"),
+    "http://example.com/?"
+  );
+
   test.done();
 };