add aio_scalar test

Author: kalombos

peewee_async.py

@@ -707,13 +707,11 @@ async def aio_scalar(self, database, as_tuple=False):
         :return: result is the same as after sync ``query.scalar()`` call
         """
         async def fetch_results(cursor):
-            row = await cursor.fetchone()
-            if row and not as_tuple:
-                return row[0]
-            else:
-                return row
+            return await cursor.fetchone()
+
+        rows = await database.aio_execute(self, fetch_results=fetch_results)
 
-        return await database.aio_execute(self, fetch_results=fetch_results)
+        return rows[0] if rows and not as_tuple else rows
 
     async def aio_get(self, database=None):
         clone = self.paginate(1, 1)

tests/aio_model/test_shortcuts.py

@@ -1,7 +1,8 @@
 import pytest
+from peewee import fn
 
 from tests.conftest import dbs_all
-from tests.models import TestModel
+from tests.models import TestModel, IntegerTestModel
 
 
 @dbs_all
@@ -28,3 +29,17 @@ async def test_aio_get_or_none(db):
 
     result = await TestModel.aio_get_or_none(TestModel.text == "unknown")
     assert result is None
+
+
+@dbs_all
+async def test_aio_scalar(db):
+    await IntegerTestModel.aio_create(num=1)
+    await IntegerTestModel.aio_create(num=2)
+
+    assert await IntegerTestModel.select(fn.MAX(IntegerTestModel.num)).aio_scalar() == 2
+
+    assert await IntegerTestModel.select(
+        fn.MAX(IntegerTestModel.num),fn.Min(IntegerTestModel.num)
+    ).aio_scalar(as_tuple=True) == (2, 1)
+
+    assert await TestModel.select().aio_scalar() is None

tests/models.py

@@ -65,7 +65,12 @@ class Meta:
         primary_key = peewee.CompositeKey('uuid', 'alpha')
 
 
+class IntegerTestModel(peewee_async.AioModel):
+    __test__ = False  # disable pytest warnings
+    num = peewee.IntegerField()
+
+
 ALL_MODELS = (
     TestModel, UUIDTestModel, TestModelAlpha, TestModelBeta, TestModelGamma,
-    CompatTestModel, CompositeTestModel
+    CompatTestModel, CompositeTestModel, IntegerTestModel
 )