add tests for mysql and postgress, some fixes for those backends

tests/test_columns.py

@@ -8,10 +8,6 @@ import sqlalchemy
 import ormar
 from tests.settings import DATABASE_URL
 
-assert "TEST_DATABASE_URLS" in os.environ, "TEST_DATABASE_URLS is not set."
-
-DATABASE_URLS = [url.strip() for url in os.environ["TEST_DATABASE_URLS"].split(",")]
-
 database = databases.Database(DATABASE_URL, force_rollback=True)
 metadata = sqlalchemy.MetaData()
 
@@ -38,45 +34,28 @@ class Example(ormar.Model):
 
 @pytest.fixture(autouse=True, scope="module")
 def create_test_database():
-    for url in DATABASE_URLS:
-        database_url = databases.DatabaseURL(url)
-        if database_url.scheme == "mysql":
-            url = str(database_url.replace(driver="pymysql"))
-        elif database_url.scheme == "postgresql+aiopg":
-            url = str(database_url.replace(driver=None))
-        engine = sqlalchemy.create_engine(url)
-        metadata.create_all(engine)
-
+    engine = sqlalchemy.create_engine(DATABASE_URL)
+    metadata.create_all(engine)
     yield
-    for url in DATABASE_URLS:
-        database_url = databases.DatabaseURL(url)
-        if database_url.scheme == "mysql":
-            url = str(database_url.replace(driver="pymysql"))
-        elif database_url.scheme == "postgresql+aiopg":
-            url = str(database_url.replace(driver=None))
-        engine = sqlalchemy.create_engine(url)
-        metadata.drop_all(engine)
+    metadata.drop_all(engine)
 
 
-@pytest.mark.parametrize("database_url", DATABASE_URLS)
 @pytest.mark.asyncio
-async def test_model_crud(database_url):
-    async with databases.Database(database_url) as database:
-        async with database.transaction(force_rollback=True):
-            Example.Meta.database = database
-            example = Example()
-            await example.save()
+async def test_model_crud():
+    async with database:
+        example = Example()
+        await example.save()
 
-            await example.load()
-            assert example.created.year == datetime.datetime.now().year
-            assert example.created_day == datetime.date.today()
-            assert example.description is None
-            assert example.value is None
-            assert example.data == {}
+        await example.load()
+        assert example.created.year == datetime.datetime.now().year
+        assert example.created_day == datetime.date.today()
+        assert example.description is None
+        assert example.value is None
+        assert example.data == {}
 
-            await example.update(data={"foo": 123}, value=123.456)
-            await example.load()
-            assert example.value == 123.456
-            assert example.data == {"foo": 123}
+        await example.update(data={"foo": 123}, value=123.456)
+        await example.load()
+        assert example.value == 123.456
+        assert example.data == {"foo": 123}
 
-            await example.delete()
+        await example.delete()