set error handler debug from run debug arg

sanic/exceptions.py

@@ -140,9 +140,9 @@ class PayloadTooLarge(SanicException):
 class Handler:
     handlers = None
 
-    def __init__(self, sanic):
+    def __init__(self):
         self.handlers = {}
-        self.sanic = sanic
+        self.debug = False
 
     def _render_traceback_html(self, exception, request):
         exc_type, exc_value, tb = sys.exc_info()
@@ -175,7 +175,7 @@ class Handler:
             response = handler(request=request, exception=exception)
         except:
             log.error(format_exc())
-            if self.sanic.debug:
+            if self.debug:
                 response_message = (
                     'Exception raised in exception handler "{}" '
                     'for uri: "{}"\n{}').format(
@@ -192,7 +192,7 @@ class Handler:
             return text(
                 'Error: {}'.format(exception),
                 status=getattr(exception, 'status_code', 500))
-        elif self.sanic.debug:
+        elif self.debug:
             html_output = self._render_traceback_html(exception, request)
 
             response_message = (

sanic/sanic.py

@@ -36,7 +36,7 @@ class Sanic:
             name = getmodulename(frame_records[1])
         self.name = name
         self.router = router or Router()
-        self.error_handler = error_handler or Handler(self)
+        self.error_handler = error_handler or Handler()
         self.config = Config()
         self.request_middleware = deque()
         self.response_middleware = deque()
@@ -300,7 +300,7 @@ class Sanic:
         :param protocol: Subclass of asyncio protocol class
         :return: Nothing
         """
-        self.error_handler.debug = True
+        self.error_handler.debug = debug
         self.debug = debug
         self.loop = loop
 

tests/test_exceptions.py

@@ -84,10 +84,29 @@ def test_handled_unhandled_exception(exception_app):
         "The server encountered an internal error and "
         "cannot complete your request.")
 
-
 def test_exception_in_exception_handler(exception_app):
     """Test that an exception thrown in an error handler is handled"""
     request, response = sanic_endpoint_test(
         exception_app, uri='/error_in_error_handler_handler')
     assert response.status == 500
     assert response.body == b'An error occurred while handling an error'
+
+
+def test_exception_in_exception_handler_debug_off(exception_app):
+    """Test that an exception thrown in an error handler is handled"""
+    request, response = sanic_endpoint_test(
+        exception_app,
+        uri='/error_in_error_handler_handler',
+        debug=False)
+    assert response.status == 500
+    assert response.body == b'An error occurred while handling an error'
+
+
+def test_exception_in_exception_handler_debug_off(exception_app):
+    """Test that an exception thrown in an error handler is handled"""
+    request, response = sanic_endpoint_test(
+        exception_app,
+        uri='/error_in_error_handler_handler',
+        debug=True)
+    assert response.status == 500
+    assert response.body.startswith(b'Exception raised in exception ')