Allow for non-mandantory date time fields

src/IDF/Form/Field/Datetime.php

@@ -0,0 +1,36 @@
+<?php
+/* -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+# ***** BEGIN LICENSE BLOCK *****
+# This file is part of InDefero, an open source project management application.
+# Copyright (C) 2008-2011 Céondo Ltd and contributors.
+#
+# InDefero is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# InDefero is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#
+# ***** END LICENSE BLOCK ***** */
+
+class IDF_Form_Field_Datetime extends Pluf_Form_Field_Datetime
+{
+    public function clean($value) {
+        try {
+            return parent::clean($value);
+        } catch (Pluf_Form_Invalid $e) {
+            if(false === $this->required and empty($value)) {
+                return null;
+            }
+            throw $e;
+        }
+    }
+}

src/IDF/Form/IssueCreate.php

@@ -112,7 +112,7 @@ class IDF_Form_IssueCreate extends Pluf_Form
                                                        'size' => 15,
                                                                     ),
                                             ));
-            $this->fields['due_dtime'] = new Pluf_Form_Field_Datetime(
+            $this->fields['due_dtime'] = new IDF_Form_Field_Datetime(
                                           array('required' => false,
                                                 'label' => __('Due date'),
                                                 'initial' => '',

src/IDF/Form/IssueUpdate.php

@@ -103,7 +103,7 @@ class IDF_Form_IssueUpdate  extends IDF_Form_IssueCreate
                                                        'size' => 15,
                                                                     ),
                                             ));
-            $this->fields['due_dtime'] = new Pluf_Form_Field_Datetime(
+            $this->fields['due_dtime'] = new IDF_Form_Field_Datetime(
                                 array('required' => false,
                                     'label' => __('Due date'),
                                     'initial' => $this->issue->due_dtime,