Add test for preventing values that are not a choice in a RadioField from being saved

tests/forms/test_base_form.py

@@ -0,0 +1,36 @@
+import pytest
+from wtforms.fields import RadioField
+from werkzeug.datastructures import ImmutableMultiDict
+
+from atst.forms.forms import BaseForm
+
+
+class FormWithChoices(BaseForm):
+    force_side = RadioField(
+        "Choose your side",
+        choices=[
+            ("light", "Light Side"),
+            ("dark", "Dark Side"),
+            ("neutral", "Chaotic Neutral"),
+        ],
+    )
+
+
+class TestBaseForm:
+    class Foo:
+        person = {"force_side": None}
+
+    obj = Foo()
+
+    def test_radio_field_saves_only_as_choice(self):
+        form_data_1 = ImmutableMultiDict({"force_side": "None"})
+        form_1 = FormWithChoices(form_data_1, obj=self.obj)
+        assert form_1.data["force_side"] is None
+
+        form_data_2 = ImmutableMultiDict({"force_side": "a fake choice"})
+        form_2 = FormWithChoices(form_data_2, obj=self.obj)
+        assert form_2.data["force_side"] is None
+
+        form_data_3 = ImmutableMultiDict({"force_side": "dark"})
+        form_3 = FormWithChoices(form_data_3, obj=self.obj)
+        assert form_3.data["force_side"] is "dark"