Fixed initialisation order (#1428)

Fixes #1424

Author: aaltat

docs/extending/extending.rst

@@ -89,6 +89,15 @@ of the attributes are explained in the library `keyword documentation`_. please
 plugins may alter the functionality of the method or attributes and documentation applies
 only for the core SeleniumLibrary.
 
+Initialisation order
+====================
+When instance is created from the SeleniumLibrary, example when library is imported in the
+test data, there is an order in the initialisation. At first all classes defining SeleniumLibrary
+keywords are discovered. As a second event, discovery for the EventFiringWebDriver is done.
+At third event, plugins are discovered. As a last event, keywords are found from SeleniumLibrary
+classes and plugins. Because plugins are discovered last, they may example alter the
+EventFiringWebDriver. Consult the plugin's documentation for more details.
+
 Plugins
 =======
 SeleniumLibrary offers plugins as a way to modify, add library keywords and modify some of the internal

src/SeleniumLibrary/__init__.py

@@ -460,17 +460,16 @@ def __init__(self, timeout=5.0, implicit_wait=0.0,
             WaitingKeywords(self),
             WindowKeywords(self)
         ]
+        self.ROBOT_LIBRARY_LISTENER = LibraryListener()
+        self._running_keyword = None
+        self.event_firing_webdriver = None
+        if is_truthy(event_firing_webdriver):
+            self.event_firing_webdriver = self._parse_listener(event_firing_webdriver)
         if is_truthy(plugins):
             plugin_libs = self._parse_plugins(plugins)
             libraries = libraries + plugin_libs
         self._drivers = WebDriverCache()
         DynamicCore.__init__(self, libraries)
-        self.ROBOT_LIBRARY_LISTENER = LibraryListener()
-        if is_truthy(event_firing_webdriver):
-            self.event_firing_webdriver = self._parse_listener(event_firing_webdriver)
-        else:
-            self.event_firing_webdriver = None
-        self._running_keyword = None
 
     def run_keyword(self, name, args, kwargs):
         self._running_keyword = name

utest/test/api/plugin_tester.py

@@ -0,0 +1,16 @@
+from SeleniumLibrary.base import LibraryComponent, keyword
+
+
+class plugin_tester(LibraryComponent):
+
+    def __init__(self, ctx):
+        LibraryComponent.__init__(self, ctx)
+        ctx.event_firing_webdriver = 'should be last'
+
+    @keyword
+    def foo(self):
+        self.info('foo')
+
+    @keyword
+    def bar(self, arg):
+        self.info(arg)

utest/test/api/test_plugins.py

@@ -103,3 +103,9 @@ def test_no_library_component_inherit(self):
         no_inherit = os.path.join(self.root_dir, 'my_lib_not_inherit.py')
         with self.assertRaises(PluginError):
             SeleniumLibrary(plugins=no_inherit)
+
+    def test_plugin_as_last_in_init(self):
+        plugin_file = os.path.join(self.root_dir, 'plugin_tester.py')
+        event_firing_wd = os.path.join(self.root_dir, 'MyListener.py')
+        sl = SeleniumLibrary(plugins=plugin_file, event_firing_webdriver=event_firing_wd)
+        self.assertEqual(sl.event_firing_webdriver, 'should be last')