Fixed #2443 -- Added DurationField.

A field for storing periods of time - modeled in Python by timedelta. It
is stored in the native interval data type on PostgreSQL and as a bigint
of microseconds on other backends.

Also includes significant changes to the internals of time related maths
in expressions, including the removal of DateModifierNode.

Thanks to Tim and Josh in particular for reviews.

1 files changed, 32 insertions, 5 deletions

diff --git a/tests/forms_tests/tests/test_fields.py b/tests/forms_tests/tests/test_fields.py
index 3caf902349..b2f0869c47 100644
--- a/tests/forms_tests/tests/test_fields.py
+++ b/tests/forms_tests/tests/test_fields.py
@@ -43,11 +43,12 @@ except ImportError:
 from django.core.files.uploadedfile import SimpleUploadedFile
 from django.forms import (
     BooleanField, CharField, ChoiceField, ComboField, DateField, DateTimeField,
-    DecimalField, EmailField, Field, FileField, FilePathField, FloatField,
-    Form, forms, HiddenInput, ImageField, IntegerField, MultipleChoiceField,
-    NullBooleanField, NumberInput, PasswordInput, RadioSelect, RegexField,
-    SplitDateTimeField, TextInput, Textarea, TimeField, TypedChoiceField,
-    TypedMultipleChoiceField, URLField, UUIDField, ValidationError, Widget,
+    DecimalField, DurationField, EmailField, Field, FileField, FilePathField,
+    FloatField, Form, forms, HiddenInput, ImageField, IntegerField,
+    MultipleChoiceField, NullBooleanField, NumberInput, PasswordInput,
+    RadioSelect, RegexField, SplitDateTimeField, TextInput, Textarea,
+    TimeField, TypedChoiceField, TypedMultipleChoiceField, URLField, UUIDField,
+    ValidationError, Widget,
 )
 from django.test import SimpleTestCase
 from django.utils import formats
@@ -611,6 +612,32 @@ class FieldsTests(SimpleTestCase):
 
     # RegexField ##################################################################
 
+    def test_durationfield_1(self):
+        f = DurationField()
+        self.assertEqual(datetime.timedelta(seconds=30), f.clean('30'))
+        self.assertEqual(
+            datetime.timedelta(minutes=15, seconds=30),
+            f.clean('15:30')
+        )
+        self.assertEqual(
+            datetime.timedelta(hours=1, minutes=15, seconds=30),
+            f.clean('1:15:30')
+        )
+        self.assertEqual(
+            datetime.timedelta(
+                days=1, hours=1, minutes=15, seconds=30, milliseconds=300),
+            f.clean('1 1:15:30.3')
+        )
+
+    def test_durationfield_2(self):
+        class DurationForm(Form):
+            duration = DurationField(initial=datetime.timedelta(hours=1))
+        f = DurationForm()
+        self.assertHTMLEqual(
+            '<input id="id_duration" type="text" name="duration" value="01:00:00">',
+            str(f['duration'])
+        )
+
     def test_regexfield_1(self):
         f = RegexField('^[0-9][A-F][0-9]$')
         self.assertEqual('2A2', f.clean('2A2'))