Clean up the tracing info for statements in error cases.

Author: carlosalberto

sqlalchemy_opentracing/__init__.py

@@ -176,6 +176,9 @@ def _engine_error_handler(exception_context):
     span.set_tag('error', 'true')
     span.finish()
 
+    if execution_context.compiled is not None:
+        clear_traced(execution_context.compiled.statement)
+
 def _register_connection_events(conn):
     '''
     Register clean up events for our

tests/test_core.py

@@ -77,6 +77,7 @@ def test_traced_error(self):
             'sqlalchemy.exception': 'table users already exists',
             'error': 'true',
         })
+        self.assertEqual(False, sqlalchemy_opentracing.get_traced(creat))
 
     def test_trace_text(self):
         tracer = DummyTracer()