SequentialTaskQueue: use finally for _scheduling

Also, remove unecessary _dirty flag.

1 files changed, 13 insertions, 33 deletions

diff --git a/pym/_emerge/SequentialTaskQueue.py b/pym/_emerge/SequentialTaskQueue.py
index 88ac844d9..3cd56d2d6 100644
--- a/pym/_emerge/SequentialTaskQueue.py
+++ b/pym/_emerge/SequentialTaskQueue.py
@@ -7,7 +7,7 @@ from collections import deque
 class SequentialTaskQueue(SlotObject):
 
 	__slots__ = ("max_jobs", "running_tasks") + \
-		("_dirty", "_scheduling", "_task_queue")
+		("_scheduling", "_task_queue")
 
 	def __init__(self, **kwargs):
 		SlotObject.__init__(self, **kwargs)
@@ -15,52 +15,34 @@ class SequentialTaskQueue(SlotObject):
 		self.running_tasks = set()
 		if self.max_jobs is None:
 			self.max_jobs = 1
-		self._dirty = True
 
 	def add(self, task):
 		self._task_queue.append(task)
-		self._dirty = True
 		self.schedule()
 
 	def addFront(self, task):
 		self._task_queue.appendleft(task)
-		self._dirty = True
 		self.schedule()
 
 	def schedule(self):
 
-		if not self._dirty:
-			return False
-
-		if not self:
-			return False
-
 		if self._scheduling:
 			# Ignore any recursive schedule() calls triggered via
 			# self._task_exit().
-			return False
+			return
 
 		self._scheduling = True
-
-		task_queue = self._task_queue
-		running_tasks = self.running_tasks
-		max_jobs = self.max_jobs
-		state_changed = False
-
-		while task_queue and \
-			(max_jobs is True or len(running_tasks) < max_jobs):
-			task = task_queue.popleft()
-			cancelled = getattr(task, "cancelled", None)
-			if not cancelled:
-				running_tasks.add(task)
-				task.addExitListener(self._task_exit)
-				task.start()
-			state_changed = True
-
-		self._dirty = False
-		self._scheduling = False
-
-		return state_changed
+		try:
+			while self._task_queue and (self.max_jobs is True or
+				len(self.running_tasks) < self.max_jobs):
+				task = self._task_queue.popleft()
+				cancelled = getattr(task, "cancelled", None)
+				if not cancelled:
+					self.running_tasks.add(task)
+					task.addExitListener(self._task_exit)
+					task.start()
+		finally:
+			self._scheduling = False
 
 	def _task_exit(self, task):
 		"""
@@ -70,7 +52,6 @@ class SequentialTaskQueue(SlotObject):
 		"""
 		self.running_tasks.remove(task)
 		if self._task_queue:
-			self._dirty = True
 			self.schedule()
 
 	def clear(self):
@@ -80,7 +61,6 @@ class SequentialTaskQueue(SlotObject):
 			task = running_tasks.pop()
 			task.removeExitListener(self._task_exit)
 			task.cancel()
-		self._dirty = False
 
 	def __bool__(self):
 		return bool(self._task_queue or self.running_tasks)