Allow for multiple date formats

tests/forms/test_fields.py

@@ -0,0 +1,25 @@
+import pytest
+from wtforms import Form
+import pendulum
+
+from atst.forms.fields import DateField
+
+
+class MyForm(Form):
+    date = DateField()
+
+
+def test_date_ie_format():
+    form = MyForm(data={"date": "12/24/2018"})
+    assert form.date._value() == pendulum.date(2018, 12, 24)
+
+
+def test_date_sane_format():
+    form = MyForm(data={"date": "2018-12-24"})
+    assert form.date._value() == pendulum.date(2018, 12, 24)
+
+
+def test_date_insane_format():
+    form = MyForm(data={"date": "hello"})
+    with pytest.raises(ValueError):
+        form.date._value()