Make document version order deterministic.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/documents/models.py

@@ -389,6 +389,11 @@ class DocumentVersion(models.Model):
         verbose_name=_('Checksum')
     )
 
+    class Meta:
+        ordering = ('timestamp',)
+        verbose_name = _('Document version')
+        verbose_name_plural = _('Document version')
+
     def __str__(self):
         return '{0} - {1}'.format(self.document, self.timestamp)
 
@@ -457,10 +462,6 @@ class DocumentVersion(models.Model):
                         sender=Document, instance=self.document
                     )
 
-    class Meta:
-        verbose_name = _('Document version')
-        verbose_name_plural = _('Document version')
-
     @property
     def cache_filename(self):
         return 'document-version-{}'.format(self.uuid)

mayan/apps/documents/tests/test_api.py

@@ -231,9 +231,9 @@ class DocumentAPITestCase(BaseAPITestCase):
         with open(TEST_DOCUMENT_PATH) as file_object:
             document.new_version(file_object=file_object)
 
-        self.assertEqual(document.versions.count(), 2)
+        document.refresh_from_db()
 
-        last_version = document.versions.last()
+        self.assertEqual(document.versions.count(), 2)
 
         response = self.client.get(
             reverse(
@@ -241,8 +241,10 @@ class DocumentAPITestCase(BaseAPITestCase):
                 args=(document.pk,)
             )
         )
+
         self.assertEqual(
-            response.data['results'][1]['checksum'], last_version.checksum
+            response.data['results'][1]['checksum'],
+            document.latest_version.checksum
         )
 
     def test_document_download(self):