Handle views on result lists

README.md

@@ -155,7 +155,19 @@ User({'_id': ObjectId(...), 'name': 'Mr. Foo', 'age': 1337})
 ### Apply views on cursors
 
 ```python
->>> for credentials in User.find().view("credentials"):
+>>> cursor = User.find()
+>>> for credentials in cursor.view("credentials"):
+...     print(credentials)
+{'username': 'MrFoo', 'password': 't0ps3cr3t'}
+{'username': 'MrsBar', 'password': '123456789'}
+...
+```
+
+And if your cursor is already exhausted, you can still apply a view!
+
+```python
+>>> users = User.find().to_list(None)
+>>> for credentials in users.view("credentials"):
 ...     print(credentials)
 {'username': 'MrFoo', 'password': 't0ps3cr3t'}
 {'username': 'MrsBar', 'password': '123456789'}

mongo_thingy/__init__.py

@@ -29,6 +29,14 @@ def __get_value(item):
         values = set(__get_value(item) for item in self)
         return list(values)
 
+    def view(self, name="defaults"):
+        def __view(item):
+            if not isinstance(item, BaseThingy):
+                raise TypeError(f"Can't view type {type(item)}.")
+            return item.view(name)
+
+        return [__view(item) for item in self]
+
 
 class BaseThingy(DatabaseThingy):
     """Represents a document in a collection"""

tests/__init__.py

@@ -37,6 +37,23 @@ async def test_thingy_list_distinct_dicts():
     assert set(distinct) == {None, "baz", "qux"}
 
 
+async def test_thingy_list_view():
+    class Foo(Thingy):
+        pass
+
+    Foo.add_view("empty")
+    foos = ThingyList()
+    foos.append(Foo(bar="baz"))
+    foos.append(Foo(bar="qux"))
+
+    for foo in foos.view("empty"):
+        assert foo == {}
+
+    foos.append({})
+    with pytest.raises(TypeError):
+        foos.view("empty")
+
+
 @pytest.mark.all_backends
 async def test_base_thingy_database(TestThingy, database):
     assert TestThingy.database == database