diff -r 000000000000 -r 6474c204b198 extensions/cookie/test/unit/test_permmanager_subdomains.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/extensions/cookie/test/unit/test_permmanager_subdomains.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,56 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function getPrincipalFromURI(uri) {
+  return Cc["@mozilla.org/scriptsecuritymanager;1"]
+           .getService(Ci.nsIScriptSecurityManager)
+           .getNoAppCodebasePrincipal(NetUtil.newURI(uri));
+}
+
+function run_test() {
+  var pm = Cc["@mozilla.org/permissionmanager;1"].
+           getService(Ci.nsIPermissionManager);
+
+  // Adds a permission to a sub-domain. Checks if it is working.
+  let sub1Principal = getPrincipalFromURI("http://sub1.example.com");
+  pm.addFromPrincipal(sub1Principal, "test/subdomains", pm.ALLOW_ACTION, 0, 0);
+  do_check_eq(pm.testPermissionFromPrincipal(sub1Principal, "test/subdomains"), pm.ALLOW_ACTION);
+
+  // A sub-sub-domain should get the permission.
+  let subsubPrincipal = getPrincipalFromURI("http://sub.sub1.example.com");
+  do_check_eq(pm.testPermissionFromPrincipal(subsubPrincipal, "test/subdomains"), pm.ALLOW_ACTION);
+
+  // Another sub-domain shouldn't get the permission.
+  let sub2Principal = getPrincipalFromURI("http://sub2.example.com");
+  do_check_eq(pm.testPermissionFromPrincipal(sub2Principal, "test/subdomains"), pm.UNKNOWN_ACTION);
+
+  // Remove current permissions.
+  pm.removeFromPrincipal(sub1Principal, "test/subdomains");
+  do_check_eq(pm.testPermissionFromPrincipal(sub1Principal, "test/subdomains"), pm.UNKNOWN_ACTION);
+
+  // Adding the permission to the main domain. Checks if it is working.
+  let mainPrincipal = getPrincipalFromURI("http://example.com");
+  pm.addFromPrincipal(mainPrincipal, "test/subdomains", pm.ALLOW_ACTION, 0, 0);
+  do_check_eq(pm.testPermissionFromPrincipal(mainPrincipal, "test/subdomains"), pm.ALLOW_ACTION);
+
+  // All sub-domains should have the permission now.
+  do_check_eq(pm.testPermissionFromPrincipal(sub1Principal, "test/subdomains"), pm.ALLOW_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(sub2Principal, "test/subdomains"), pm.ALLOW_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(subsubPrincipal, "test/subdomains"), pm.ALLOW_ACTION);
+
+  // Remove current permissions.
+  pm.removeFromPrincipal(mainPrincipal, "test/subdomains");
+  do_check_eq(pm.testPermissionFromPrincipal(mainPrincipal, "test/subdomains"), pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(sub1Principal, "test/subdomains"), pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(sub2Principal, "test/subdomains"), pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(subsubPrincipal, "test/subdomains"), pm.UNKNOWN_ACTION);
+
+  // A sanity check that the previous implementation wasn't passing...
+  let crazyPrincipal = getPrincipalFromURI("http://com");
+  pm.addFromPrincipal(crazyPrincipal, "test/subdomains", pm.ALLOW_ACTION, 0, 0);
+  do_check_eq(pm.testPermissionFromPrincipal(crazyPrincipal, "test/subdomains"),  pm.ALLOW_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(mainPrincipal, "test/subdomains"),   pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(sub1Principal, "test/subdomains"),   pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(sub2Principal, "test/subdomains"),   pm.UNKNOWN_ACTION);
+  do_check_eq(pm.testPermissionFromPrincipal(subsubPrincipal, "test/subdomains"), pm.UNKNOWN_ACTION);
+}
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