improved numlock correction

keymapper/dev/injector.py

@@ -58,10 +58,15 @@ def is_numlock_on():
     return False
 
 
-def toggle_numlock():
-    """Turn the numlock on or off."""
+def set_numlock(state):
+    """Set the numlock to a given state of True or False."""
+    value = {
+        True: 'on',
+        False: 'off'
+    }[state]
+
     try:
-        subprocess.check_output(['numlockx', 'toggle'])
+        subprocess.check_output(['numlockx', value])
     except FileNotFoundError:
         # doesn't seem to be installed everywhere
         logger.debug('numlockx not found')
@@ -74,10 +79,7 @@ def ensure_numlock(func):
         # remember it and apply back later
         numlock_before = is_numlock_on()
         result = func(*args, **kwargs)
-        numlock_after = is_numlock_on()
-        if numlock_after != numlock_before:
-            logger.debug('Reverting numlock status to %s', numlock_before)
-            toggle_numlock()
+        set_numlock(numlock_before)
         return result
     return wrapped
 
@@ -282,6 +284,8 @@ class KeycodeInjector:
         Stuff is non-blocking by using asyncio in order to do multiple things
         somewhat concurrently.
         """
+        numlock_state = is_numlock_on()
+
         loop = asyncio.get_event_loop()
         coroutines = []
 
@@ -345,6 +349,10 @@ class KeycodeInjector:
 
         coroutines.append(self._msg_listener(loop))
 
+        # set the numlock state to what it was before injecting, because
+        # grabbing devices screws this up
+        set_numlock(numlock_state)
+
         try:
             loop.run_until_complete(asyncio.gather(*coroutines))
         except RuntimeError:

tests/testcases/test_injector.py

@@ -26,7 +26,7 @@ import copy
 import evdev
 from evdev.ecodes import EV_REL, EV_KEY, EV_ABS, ABS_HAT0X
 
-from keymapper.dev.injector import is_numlock_on, toggle_numlock, \
+from keymapper.dev.injector import is_numlock_on, set_numlock, \
     ensure_numlock, KeycodeInjector
 from keymapper.state import custom_mapping, system_mapping
 from keymapper.mapping import Mapping
@@ -212,12 +212,12 @@ class TestInjector(unittest.TestCase):
     def test_numlock(self):
         before = is_numlock_on()
 
-        toggle_numlock()  # should change
+        set_numlock(not before)  # should change
         self.assertEqual(not before, is_numlock_on())
 
         @ensure_numlock
         def wrapped_1():
-            toggle_numlock()
+            set_numlock(not is_numlock_on())
 
         @ensure_numlock
         def wrapped_2():
@@ -230,7 +230,7 @@ class TestInjector(unittest.TestCase):
         self.assertEqual(not before, is_numlock_on())
 
         # toggle one more time to restore the previous configuration
-        toggle_numlock()
+        set_numlock(before)
         self.assertEqual(before, is_numlock_on())
 
     def test_abs_to_rel(self):
@@ -290,6 +290,8 @@ class TestInjector(unittest.TestCase):
         self.assertAlmostEqual(history[-2][2], -1)
 
     def test_injector(self):
+        numlock_before = is_numlock_on()
+
         custom_mapping.change((EV_KEY, 8), 'k(KEY_Q).k(w)')
         custom_mapping.change((EV_ABS, ABS_HAT0X), 'a')
         # one mapping that is unknown in the system_mapping on purpose
@@ -373,6 +375,9 @@ class TestInjector(unittest.TestCase):
         time.sleep(0.1)
         self.assertTrue(self.injector._process.is_alive())
 
+        numlock_after = is_numlock_on()
+        self.assertEqual(numlock_before, numlock_after)
+
 
 if __name__ == "__main__":
     unittest.main()