diff --git a/bopytex/scheduler.py b/bopytex/scheduler.py
index db00b12..8155f1c 100644
--- a/bopytex/scheduler.py
+++ b/bopytex/scheduler.py
@@ -1,6 +1,9 @@
 """ Scheduler for action to make """
 
 
+from logging import exception
+
+
 class Scheduler:
     def __init__(self, actions: list):
         self.actions = actions
@@ -23,15 +26,32 @@ class Scheduler:
         ans = self.actions[task.action](task.deps, task.args)
         return ans
 
+    def __iter__(self):
+        return self
     def __next__(self):
+        return self.next()
+
+    def next(self):
         undoable = []
 
-        task = self._tasks.pop(0)
+        try:
+            task = self._tasks.pop(0)
+        except IndexError:
+            raise StopIteration
+
         while not all([d in self.done for d in task.deps]):
             undoable.append(task)
-            task = self._tasks.pop(0)
+            try:
+                task = self._tasks.pop(0)
+            except IndexError:
+                self.append(undoable)
+                raise StopIteration
 
         self.append(undoable)
         ans = self.dispatch(task)
         self._done.append(ans)
         return ans
+
+    def run(self):
+        for i in self:
+            pass
diff --git a/test/test_scheduler.py b/test/test_scheduler.py
index a79c764..9176e6e 100644
--- a/test/test_scheduler.py
+++ b/test/test_scheduler.py
@@ -1,5 +1,6 @@
 from bopytex.planner import Task
 from bopytex.scheduler import Scheduler
+import pytest
 
 
 def test_schedule_append():
@@ -22,7 +23,7 @@ def test_schedule_one_task():
     actions = {"DO": lambda deps, args: "done"}
     scheduler = Scheduler(actions)
     scheduler.append([Task(action="DO", args={}, deps=[])])
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "done"
     assert scheduler.tasks == []
     assert scheduler.done == ["done"]
@@ -32,7 +33,7 @@ def test_schedule_one_task_with_args():
     actions = {"DO": lambda deps, args: f"{args['task']} done"}
     scheduler = Scheduler(actions)
     scheduler.append([Task(action="DO", args={"task": "one"}, deps=[])])
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "one done"
     assert scheduler.tasks == []
     assert scheduler.done == ["one done"]
@@ -45,17 +46,17 @@ def test_schedule_multiple_tasks():
     t2 = Task(action="DO", args={"task": "two"}, deps=[])
     t3 = Task(action="DO", args={"task": "three"}, deps=[])
     scheduler.append([t1, t2, t3])
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "one done"
     assert scheduler.tasks == [t2, t3]
     assert scheduler.done == ["one done"]
 
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "two done"
     assert scheduler.tasks == [t3]
     assert scheduler.done == ["one done", "two done"]
 
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "three done"
     assert scheduler.tasks == []
     assert scheduler.done == ["one done", "two done", "three done"]
@@ -69,18 +70,37 @@ def test_schedule_multiple_tasks_with_dependencies():
     t3 = Task(action="DO", args={"task": "three"}, deps=[])
     scheduler.append([t1, t2, t3])
 
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "three done"
     assert scheduler.tasks == [t1, t2]
     assert scheduler.done == ["three done"]
 
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "one done"
     assert scheduler.tasks == [t2]
     assert scheduler.done == ["three done", "one done"]
 
-    result = scheduler.__next__()
+    result = scheduler.next()
     assert result == "two done"
     assert scheduler.tasks == []
     assert scheduler.done == ["three done", "one done", "two done"]
 
+
+def test_schedule_empty_task():
+    actions = {"DO": lambda deps, args: f"{args['task']} done"}
+    scheduler = Scheduler(actions)
+    scheduler.append([])
+    with pytest.raises(StopIteration):
+        scheduler.next()
+
+
+def test_schedule_multiple_tasks_with_undoable_dependencies():
+    actions = {"DO": lambda deps, args: f"{args['task']} done"}
+    scheduler = Scheduler(actions)
+    t1 = Task(action="DO", args={"task": "one"}, deps=["three done"])
+    t2 = Task(action="DO", args={"task": "two"}, deps=[])
+    scheduler.append([t1, t2])
+    scheduler.run()
+    assert scheduler.tasks == [t1]
+    assert scheduler.done == ["two done"]
+