Improve test coverage

Author: Connor Brinton

Diff for: graphene_sqlalchemy/tests/test_types.py

@@ -1,7 +1,10 @@
 from collections import OrderedDict
 from graphene import Field, Int, Interface, ObjectType
 from graphene.relay import Node, is_node, Connection
+import mock
 import six
+import sqlalchemy.exc
+import sqlalchemy.orm.exc
 from promise import Promise
 
 from .. import utils
@@ -184,33 +187,63 @@ class Meta:
     assert result is not None
 
 
-def test_errors_propagated():
-    # Get current `class_mapper` value
-    old_class_mapper = utils.class_mapper
+@mock.patch(utils.__name__ + '.class_mapper')
+def test_unique_errors_propagate(class_mapper_mock):
+    # Define unique error to detect
+    class UniqueError(Exception):
+        pass
 
+    # Mock class_mapper effect
+    class_mapper_mock.side_effect = UniqueError
+
+    # Make sure that errors are propagated from class_mapper when instantiating new classes
+    error = None
+    try:
+        class ArticleOne(SQLAlchemyObjectType):
+            class Meta(object):
+                model = Article
+    except UniqueError as e:
+        error = e
+
+    # Check that an error occured, and that it was the unique error we gave
+    assert error is not None
+    assert isinstance(error, UniqueError)
+
+
+@mock.patch(utils.__name__ + '.class_mapper')
+def test_argument_errors_propagate(class_mapper_mock):
+    # Mock class_mapper effect
+    class_mapper_mock.side_effect = sqlalchemy.exc.ArgumentError
+
+    # Make sure that errors are propagated from class_mapper when instantiating new classes
+    error = None
+    try:
+        class ArticleTwo(SQLAlchemyObjectType):
+            class Meta(object):
+                model = Article
+    except sqlalchemy.exc.ArgumentError as e:
+        error = e
+
+    # Check that an error occured, and that it was the unique error we gave
+    assert error is not None
+    assert isinstance(error, sqlalchemy.exc.ArgumentError)
+
+
+@mock.patch(utils.__name__ + '.class_mapper')
+def test_unmapped_errors_reformat(class_mapper_mock):
+    # Mock class_mapper effect
+    class_mapper_mock.side_effect = sqlalchemy.orm.exc.UnmappedClassError(object)
+
+    # Make sure that errors are propagated from class_mapper when instantiating new classes
+    error = None
     try:
-        # Define unique error to detect
-        class UniqueError(Exception):
-            pass
-
-        # Redefine `class_mapper` in utils
-        def new_class_mapper(*args, **kwargs):
-            raise UniqueError()
-        utils.class_mapper = new_class_mapper
-
-        # Make sure that errors are propagated from class_mapper when instantiating classes
-        error = None
-        try:
-            class Tree(SQLAlchemyObjectType):
-                class Meta(object):
-                    model = Article
-
-        except UniqueError as e:
-            error = e
-
-        # Check that an error occured, and that it was a SQLAlchemy error
-        assert error is not None
-        assert isinstance(error, UniqueError)
-    finally:
-        # Restore original class mapper
-        utils.class_mapper = old_class_mapper
+        class ArticleThree(SQLAlchemyObjectType):
+            class Meta(object):
+                model = Article
+    except ValueError as e:
+        error = e
+
+    # Check that an error occured, and that it was the unique error we gave
+    assert error is not None
+    assert isinstance(error, ValueError)
+    assert "You need to pass a valid SQLAlchemy Model" in str(error)