From 1326ab5004c2dcc40a34ae4ee77873dbd047a20e Mon Sep 17 00:00:00 2001
From: Sven Augustin <sven.augustin@psi.ch>
Date: Fri, 15 May 2020 10:34:16 +0000
Subject: [PATCH] added re-raise of exceptions and returning the result of
 func() to Task.wait()

---
 slic/core/task/task.py | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/slic/core/task/task.py b/slic/core/task/task.py
index 730164010..ed898bdb6 100644
--- a/slic/core/task/task.py
+++ b/slic/core/task/task.py
@@ -10,20 +10,31 @@ class Task(BaseTask):
     def __init__(self, func, stopper=None, hold=True):
         self.func = func
         self.stopper = stopper
-        self.thread = Thread(target=func)
+        self.thread = Thread(target=self.target)
+        self.result = None
+        self.exception = None
         if not hold:
             self.start()
 
+    def target(self):
+        try:
+            self.result = self.func()
+        except BaseException as exc: # BaseException covers a few more cases than Exception
+            self.exception = exc
+
     def start(self):
         self.thread.start()
 
     def stop(self):
         if self.stopper is not None:
             self.stopper()
-        self.thread.join()
+        return self.wait()
 
     def wait(self):
         self.thread.join()
+        if self.exception:
+            raise TaskError from self.exception
+        return self.result
 
     @property
     def status(self):
@@ -39,3 +50,10 @@ class Task(BaseTask):
 
 
 
+class TaskError(RuntimeError):
+    def __init__(self):
+        message = "Exception in Task"
+        super().__init__(message)
+
+
+