michael@0: 
michael@0: function getTestPlugin(pluginName) {
michael@0:   var ph = SpecialPowers.Cc["@mozilla.org/plugin/host;1"]
michael@0:                                  .getService(SpecialPowers.Ci.nsIPluginHost);
michael@0:   var tags = ph.getPluginTags();
michael@0:   var name = pluginName || "Test Plug-in";
michael@0:   for (var tag of tags) {
michael@0:     if (tag.name == name) {
michael@0:       return tag;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   ok(false, "Could not find plugin tag with plugin name '" + name + "'");
michael@0:   return null;
michael@0: }
michael@0: 
michael@0: // call this to set the test plugin(s) initially expected enabled state.
michael@0: // it will automatically be reset to it's previous value after the test
michael@0: // ends
michael@0: function setTestPluginEnabledState(newEnabledState, pluginName) {
michael@0:   var plugin = getTestPlugin(pluginName);
michael@0:   var oldEnabledState = plugin.enabledState;
michael@0:   plugin.enabledState = newEnabledState;
michael@0:   SimpleTest.registerCleanupFunction(function() {
michael@0:     getTestPlugin(pluginName).enabledState = oldEnabledState;
michael@0:   });
michael@0: }