From 1c5278cebfc0e870e263a4f2ee42a7bd548524ce Mon Sep 17 00:00:00 2001
From: Christopher Charbonneau Wells <chris@chrxs.net>
Date: Tue, 7 Nov 2017 07:07:51 -0500
Subject: [PATCH] Verify necessary fields before running model validation
 tests.

---
 core/models.py            | 11 ++++++-----
 core/tests/tests_forms.py |  2 +-
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/core/models.py b/core/models.py
index 367045bd..2bfae0b0 100644
--- a/core/models.py
+++ b/core/models.py
@@ -36,10 +36,11 @@ def validate_unique_period(queryset, model):
     """
     if model.id:
         queryset = queryset.exclude(id=model.id)
-    if queryset.filter(start__lte=model.end, end__gte=model.start):
-        raise ValidationError(
-            'Another entry already exists within the specified time period.',
-            code='period_intersection')
+    if model.start and model.end:
+        if queryset.filter(start__lte=model.end, end__gte=model.start):
+            raise ValidationError(
+                'Another entry intersects the specified time period.',
+                code='period_intersection')
 
 
 def validate_time(time, field_name):
@@ -49,7 +50,7 @@ def validate_time(time, field_name):
     :param field_name: the name of the field being checked.
     :return:
     """
-    if time > timezone.localtime():
+    if time and time > timezone.localtime():
         raise ValidationError(
             {field_name: 'Date/time can not be in the future.'},
             code='time_invalid')
diff --git a/core/tests/tests_forms.py b/core/tests/tests_forms.py
index f60486f8..06341d8b 100644
--- a/core/tests/tests_forms.py
+++ b/core/tests/tests_forms.py
@@ -238,4 +238,4 @@ class FormsTestCase(TestCase):
             page,
             'form',
             None,
-            'Another entry already exists within the specified time period.')
+            'Another entry intersects the specified time period.')