Make it use existing shutdown events

Also adds check to powerline-lint that "args" dictionary does not set
shutdown_event, segment_info or pl keyword arguments, this will lead to problems

powerline/__init__.py

@@ -235,6 +235,7 @@ class Powerline(object):
 						'ext': self.ext,
 						'common_config': self.common_config,
 						'run_once': self.run_once,
+						'shutdown_event': self.shutdown_event,
 					},
 				)
 

powerline/lib/threaded.py

@@ -34,7 +34,6 @@ class ThreadedSegment(MultiRunnedThread):
 
 	def __init__(self):
 		super(ThreadedSegment, self).__init__()
-		self.shutdown_event = Event()
 		self.run_once = True
 		self.skip = False
 		self.crashed_value = None
@@ -98,8 +97,9 @@ class ThreadedSegment(MultiRunnedThread):
 		interval = interval or getattr(self, 'interval')
 		self.interval = interval
 
-	def set_state(self, interval=None, update_first=True, **kwargs):
+	def set_state(self, interval=None, update_first=True, shutdown_event=None, **kwargs):
 		self.set_interval(interval)
+		self.shutdown_event = shutdown_event or Event()
 		self.updated = not (update_first and self.update_first)
 
 	def startup(self, pl, **kwargs):
@@ -177,8 +177,9 @@ class KwThreadedSegment(ThreadedSegment):
 
 		return update_value
 
-	def set_state(self, interval=None, **kwargs):
+	def set_state(self, interval=None, shutdown_event=None, **kwargs):
 		self.set_interval(interval)
+		self.shutdown_event = shutdown_event or Event()
 
 	@staticmethod
 	def render_one(update_state, **kwargs):

powerline/lint/__init__.py

@@ -242,6 +242,11 @@ class Spec(object):
 						msg_func))
 		return self
 
+	def error(self, msg):
+		self.checks.append(('check_func', lambda *args: (True, True, True),
+							lambda value: msg.format(value)))
+		return self
+
 	def either(self, *specs):
 		start = len(self.specs)
 		self.specs.extend(specs)
@@ -788,6 +793,9 @@ def check_segment_data_key(key, data, context, echoerr):
 args_spec = Spec(
 	interval=Spec().either(Spec().type(float), Spec().type(int)).optional(),
 	update_first=Spec().type(bool).optional(),
+	shutdown_event=Spec().error('Shutdown event must be set by powerline').optional(),
+	pl=Spec().error('pl object must be set by powerline').optional(),
+	segment_info=Spec().error('Segment info dictionary must be set by powerline').optional(),
 ).unknown_spec(Spec(), Spec()).optional().copy
 highlight_group_spec = Spec().type(unicode).copy
 segment_module_spec = Spec().type(unicode).func(check_segment_module).optional().copy

powerline/theme.py

@@ -22,7 +22,14 @@ def requires_segment_info(func):
 
 
 class Theme(object):
-	def __init__(self, ext, theme_config, common_config, pl, top_theme_config=None, run_once=False):
+	def __init__(self,
+				ext,
+				theme_config,
+				common_config,
+				pl,
+				top_theme_config=None,
+				run_once=False,
+				shutdown_event=None):
 		self.dividers = theme_config.get('dividers', common_config['dividers'])
 		self.spaces = theme_config.get('spaces', common_config['spaces'])
 		self.segments = {
@@ -44,7 +51,7 @@ class Theme(object):
 				if not run_once:
 					if segment['startup']:
 						try:
-							segment['startup'](pl=pl, **segment['args'])
+							segment['startup'](pl=pl, shutdown_event=shutdown_event, **segment['args'])
 						except Exception as e:
 							pl.error('Exception during {0} startup: {1}', segment['name'], str(e))
 							continue