Initial commit of TimedeltaField, with some really basic tests.

Author: Roy Smith

fields/fields.py

@@ -0,0 +1,40 @@
+from datetime import timedelta
+from mongoengine.base import BaseField
+
+class TimedeltaField(BaseField):
+    """A timedelta field.
+
+    Looks to the outside world like a datatime.timedelta, but stores
+    in the database as an integer (or float) number of seconds.
+    
+    """
+    def validate(self, value):
+        if not isinstance(value, (timedelta, int, float)):
+            self.error(u'cannot parse timedelta "%r"' % value)
+
+    def to_mongo(self, value):
+        return self.prepare_query_value(None, value)
+
+    def to_python(self, value):
+        return timedelta(seconds=value)
+
+    def prepare_query_value(self, op, value):
+        if value is None:
+            return value
+        if isinstance(value, timedelta):
+            return self.total_seconds(value)
+        if isinstance(value, (int, float)):
+            return value
+
+    @staticmethod
+    def total_seconds(value):
+        """Implements Python 2.7's datetime.timedelta.total_seconds()
+        for backwards compatibility with Python 2.5 and 2.6.
+
+        """
+        try:
+            return value.total_seconds()
+        except AttributeError:
+            return (value.days * 24 * 3600) + \
+                   (value.seconds) + \
+                   (value.microseconds / 1000000.0)

fields/test_fields.py

@@ -0,0 +1,26 @@
+import unittest2 as unittest
+from datetime import timedelta
+from fields import TimedeltaField
+
+class OldStyleTimedelta(timedelta):
+    "Used for backwards compatibility testing"
+    def total_seconds(self):
+        raise AttributeError
+
+class TimedeltaFieldTestCase(unittest.TestCase):
+    def setUp(self):
+        self.field = TimedeltaField()
+
+    def test_construct(self):
+        self.assertIsInstance(self.field, TimedeltaField)
+
+    def test_total_seconds(self):
+        value = timedelta(minutes=1, seconds=10)
+        self.assertEqual(self.field.total_seconds(value), 70)
+
+    def test_total_seconds_26(self):
+        value = OldStyleTimedelta(minutes=1, seconds=10)
+        self.assertEqual(self.field.total_seconds(value), 70)
+
+if __name__ == '__main__':
+    unittest.main()