fail gracefully when dill has error, issues #155, #169

Author: machow

pythonwhat/tasks.py

@@ -259,7 +259,7 @@ def getRepresentation(name, process):
         try:
             stream = getStreamPickle(name, process)
             if not errored(stream): return pickle.loads(stream)
-        except PicklingError: 
+        except: 
             pass
 
         # if it failed, try to dill
@@ -268,7 +268,10 @@ def getRepresentation(name, process):
             if not errored(stream): return dill.loads(stream)
             return ReprFail("dilling inside process failed for %s - write manual converter" % obj_class)
         except PicklingError:
-            return ReprFail("undilling of bytestream failed - write manual converter")
+            return ReprFail("undilling of bytestream failed with PicklingError - write manual converter")
+        except Exception as e:
+            return ReprFail("undilling of bytestream failed for class %s - write manual converter."
+                            "Error: %s - %s" % (obj_class, type(e), e))
 
 def errored(el):
     return el is None or (isinstance(el, list) and 'backend-error' in str(el))

tests/test_test_function.py

@@ -660,7 +660,7 @@ def test_nohighlight_too_few_calls(self):
         self.assertEqual(sct_payload.get('line_start'), None)
 
 
-class TestFunctionWithFunctionArg(unittest.TestCase):
+class TestFunctionComplexArgs(unittest.TestCase):
     def setUp(self):
         self.data = {
                 "DC_SOLUTION": """
@@ -671,22 +671,37 @@ def apply(f, arr): return f(arr)
 apply(sum2, [1,2,3])
 """,
                 "DC_SCT": """
-def sum2(arr): return sum(arr)
 test_function('apply')
 """
                 }
         self.data["DC_CODE"] = self.data["DC_SOLUTION"]
 
-    @unittest.skip("Can't unpickle user def funcs, but doesn't throw PicklingError (see issue #155)")
-    def test_pass(self):
+    def test_function_with_funcarg_fails(self):
+        # because functions are shipped across student and submission processes
+        # they are always "unequal".
         sct_payload = helper.run(self.data)
-        self.assertTrue(sct_payload['correct'])
+        self.assertFalse(sct_payload['correct'])
 
-    def test_pass_v2(self):
+    def test_pass_with_no_eval(self):
         self.data["DC_SCT"] = """test_function_v2('apply', params=['f', 'arr'], do_eval=[False, True])"""
         sct_payload = helper.run(self.data)
         self.assertTrue(sct_payload['correct'])
 
+    def test_fail_undillable_args(self):
+        self.data = {
+                "DC_PEC": """
+import pickle; from io import BytesIO
+
+file = BytesIO(pickle.dumps('abc'))
+        """,
+                "DC_SOLUTION": "d = pickle.load(file); print(d)",
+                "DC_CODE": "print(file)",
+                "DC_SCT": """test_function("print", index=1)"""
+                }
+        sct_payload = helper.run(self.data)
+        self.assertFalse(sct_payload['correct'])
+
+
 
 
 if __name__ == "__main__":