scanner: Fix scanner.update_library() function

We were scheduling the CheckTask, but not following up with a
DirectoryTask to scan for new files. I use this function during the
Gtk.Application startup to automatically update the libraries.

Implements #31 (Automatically update the database during startup)
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

emmental.py

@@ -16,6 +16,8 @@ class Application(Gtk.Application):
     def do_startup(self):
         Gtk.Application.do_startup(self)
         self.add_window(ui.window.Window())
+        for i in range(db.library.Table.get_n_items()):
+            scanner.update_library(db.library.Table.get_item(i))
 
     def do_activate(self):
         for window in self.get_windows():

scanner/__init__.py

@@ -31,6 +31,7 @@ def commit():
 
 def update_library(lib):
     Queue.push(task.CheckSchedulerTask(lib))
+    Queue.push(task.DirectoryTask(lib, lib.path))
 
 def remove_library(lib):
     Queue.push(task.RemoveLibrarySchedulerTask(lib))

scanner/test_scanner.py

@@ -20,6 +20,8 @@ class TestScanner(unittest.TestCase):
         scanner.update_library(lib)
         self.assertIsInstance(scanner.Queue.tasks[0],
                               scanner.task.CheckSchedulerTask)
+        self.assertIsInstance(scanner.Queue.tasks[1],
+                              scanner.task.DirectoryTask)
 
     def test_remove_library(self):
         lib = db.library.Table.find(test_album)