diff --git a/app/Helper/TaskHelper.php b/app/Helper/TaskHelper.php
index ce39eb2a7..84b41e42e 100644
--- a/app/Helper/TaskHelper.php
+++ b/app/Helper/TaskHelper.php
@@ -70,6 +70,7 @@ class TaskHelper extends Base
         $options = $this->tagModel->getAssignableList($project['id']);
 
         $html = $this->helper->form->label(t('Tags'), 'tags[]');
+        $html .= '<input type="hidden" name="tags[]" value="">';
         $html .= '<select name="tags[]" id="form-tags" class="tag-autocomplete" multiple>';
 
         foreach ($options as $tag) {
diff --git a/app/Model/TaskModificationModel.php b/app/Model/TaskModificationModel.php
index 1b176a416..be5f53c8c 100644
--- a/app/Model/TaskModificationModel.php
+++ b/app/Model/TaskModificationModel.php
@@ -108,8 +108,6 @@ class TaskModificationModel extends Base
         if (isset($values['tags'])) {
             $this->taskTagModel->save($original_task['project_id'], $values['id'], $values['tags']);
             unset($values['tags']);
-        } else {
-            $this->taskTagModel->save($original_task['project_id'], $values['id'], array());
         }
     }
 }
diff --git a/app/Model/TaskTagModel.php b/app/Model/TaskTagModel.php
index 91dfd2241..2a08e8675 100644
--- a/app/Model/TaskTagModel.php
+++ b/app/Model/TaskTagModel.php
@@ -82,6 +82,7 @@ class TaskTagModel extends Base
     public function save($project_id, $task_id, array $tags)
     {
         $task_tags = $this->getList($task_id);
+        $tags = array_filter($tags);
 
         return $this->associateTags($project_id, $task_id, $task_tags, $tags) &&
             $this->dissociateTags($task_id, $task_tags, $tags);
diff --git a/tests/units/Model/TaskModificationModelTest.php b/tests/units/Model/TaskModificationModelTest.php
new file mode 100644
index 000000000..c81f968b9
--- /dev/null
+++ b/tests/units/Model/TaskModificationModelTest.php
@@ -0,0 +1,322 @@
+<?php
+
+require_once __DIR__.'/../Base.php';
+
+use Kanboard\Model\TaskModel;
+use Kanboard\Model\TaskCreationModel;
+use Kanboard\Model\TaskModificationModel;
+use Kanboard\Model\TaskFinderModel;
+use Kanboard\Model\ProjectModel;
+use Kanboard\Model\TaskTagModel;
+
+class TaskModificationModelTest extends Base
+{
+    public function onCreateUpdate($event)
+    {
+        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
+
+        $event_data = $event->getAll();
+        $this->assertNotEmpty($event_data);
+        $this->assertEquals(1, $event_data['task_id']);
+        $this->assertEquals('Task #1', $event_data['title']);
+    }
+
+    public function onUpdate($event)
+    {
+        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
+
+        $event_data = $event->getAll();
+        $this->assertNotEmpty($event_data);
+        $this->assertEquals(1, $event_data['task_id']);
+        $this->assertEquals('Task #1', $event_data['title']);
+    }
+
+    public function onAssigneeChange($event)
+    {
+        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
+
+        $event_data = $event->getAll();
+        $this->assertNotEmpty($event_data);
+        $this->assertEquals(1, $event_data['task_id']);
+        $this->assertEquals(1, $event_data['owner_id']);
+    }
+
+    public function testThatNoEventAreFiredWhenNoChanges()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $this->container['dispatcher']->addListener(TaskModel::EVENT_CREATE_UPDATE, array($this, 'onCreateUpdate'));
+        $this->container['dispatcher']->addListener(TaskModel::EVENT_UPDATE, array($this, 'onUpdate'));
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'title' => 'test')));
+
+        $this->assertEmpty($this->container['dispatcher']->getCalledListeners());
+    }
+
+    public function testChangeTitle()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $this->container['dispatcher']->addListener(TaskModel::EVENT_CREATE_UPDATE, array($this, 'onCreateUpdate'));
+        $this->container['dispatcher']->addListener(TaskModel::EVENT_UPDATE, array($this, 'onUpdate'));
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'title' => 'Task #1')));
+
+        $called = $this->container['dispatcher']->getCalledListeners();
+        $this->assertArrayHasKey(TaskModel::EVENT_CREATE_UPDATE.'.TaskModificationModelTest::onCreateUpdate', $called);
+        $this->assertArrayHasKey(TaskModel::EVENT_UPDATE.'.TaskModificationModelTest::onUpdate', $called);
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('Task #1', $task['title']);
+    }
+
+    public function testChangeAssignee()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['owner_id']);
+
+        $this->container['dispatcher']->addListener(TaskModel::EVENT_ASSIGNEE_CHANGE, array($this, 'onAssigneeChange'));
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'owner_id' => 1)));
+
+        $called = $this->container['dispatcher']->getCalledListeners();
+        $this->assertArrayHasKey(TaskModel::EVENT_ASSIGNEE_CHANGE.'.TaskModificationModelTest::onAssigneeChange', $called);
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(1, $task['owner_id']);
+    }
+
+    public function testChangeDescription()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('', $task['description']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'description' => 'test')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('test', $task['description']);
+    }
+
+    public function testChangeCategory()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['category_id']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'category_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(1, $task['category_id']);
+    }
+
+    public function testChangeColor()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('yellow', $task['color_id']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'color_id' => 'blue')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('blue', $task['color_id']);
+    }
+
+    public function testChangeScore()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['score']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'score' => 13)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(13, $task['score']);
+    }
+
+    public function testChangeDueDate()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['date_due']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_due' => '2014-11-24')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('2014-11-24', date('Y-m-d', $task['date_due']));
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_due' => time())));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(date('Y-m-d'), date('Y-m-d', $task['date_due']));
+    }
+
+    public function testChangeStartedDate()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['date_started']);
+
+        // Set only a date
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_started' => '2014-11-24')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('2014-11-24 '.date('H:i'), date('Y-m-d H:i', $task['date_started']));
+
+        // Set a datetime
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_started' => '2014-11-24 16:25')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('2014-11-24 16:25', date('Y-m-d H:i', $task['date_started']));
+
+        // Set a datetime
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_started' => '11/24/2014 18:25')));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals('2014-11-24 18:25', date('Y-m-d H:i', $task['date_started']));
+
+        // Set a timestamp
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'date_started' => time())));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(time(), $task['date_started'], '', 1);
+    }
+
+    public function testChangeTimeEstimated()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['time_estimated']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'time_estimated' => 13.3)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(13.3, $task['time_estimated']);
+    }
+
+    public function testChangeTimeSpent()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskFinderModel = new TaskFinderModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(0, $task['time_spent']);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'time_spent' => 13.3)));
+
+        $task = $taskFinderModel->getById(1);
+        $this->assertEquals(13.3, $task['time_spent']);
+    }
+
+    public function testChangeTags()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskTagModel = new TaskTagModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1, 'tags' => array('tag1', 'tag2'))));
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'tags' => array('tag2'))));
+
+        $tags = $taskTagModel->getList(1);
+        $this->assertEquals(array(2 => 'tag2'), $tags);
+    }
+
+    public function testRemoveAllTags()
+    {
+        $projectModel = new ProjectModel($this->container);
+        $taskCreationModel = new TaskCreationModel($this->container);
+        $taskModificationModel = new TaskModificationModel($this->container);
+        $taskTagModel = new TaskTagModel($this->container);
+
+        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
+        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test1', 'project_id' => 1, 'tags' => array('tag1', 'tag2'))));
+        $this->assertEquals(2, $taskCreationModel->create(array('title' => 'test2', 'project_id' => 1, 'tags' => array('tag1', 'tag2'))));
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1)));
+        $tags = $taskTagModel->getList(1);
+        $this->assertEquals(array(1 => 'tag1', 2 => 'tag2'), $tags);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'tags' => array())));
+        $tags = $taskTagModel->getList(1);
+        $this->assertEquals(array(), $tags);
+
+        $this->assertTrue($taskModificationModel->update(array('id' => 2, 'tags' => array(''))));
+        $tags = $taskTagModel->getList(2);
+        $this->assertEquals(array(), $tags);
+    }
+}
diff --git a/tests/units/Model/TaskModificationTest.php b/tests/units/Model/TaskModificationTest.php
deleted file mode 100644
index 5cbc44e60..000000000
--- a/tests/units/Model/TaskModificationTest.php
+++ /dev/null
@@ -1,313 +0,0 @@
-<?php
-
-require_once __DIR__.'/../Base.php';
-
-use Kanboard\Model\TaskModel;
-use Kanboard\Model\TaskCreationModel;
-use Kanboard\Model\TaskModificationModel;
-use Kanboard\Model\TaskFinderModel;
-use Kanboard\Model\ProjectModel;
-use Kanboard\Model\TaskTagModel;
-
-class TaskModificationTest extends Base
-{
-    public function onCreateUpdate($event)
-    {
-        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
-
-        $event_data = $event->getAll();
-        $this->assertNotEmpty($event_data);
-        $this->assertEquals(1, $event_data['task_id']);
-        $this->assertEquals('Task #1', $event_data['title']);
-    }
-
-    public function onUpdate($event)
-    {
-        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
-
-        $event_data = $event->getAll();
-        $this->assertNotEmpty($event_data);
-        $this->assertEquals(1, $event_data['task_id']);
-        $this->assertEquals('Task #1', $event_data['title']);
-    }
-
-    public function onAssigneeChange($event)
-    {
-        $this->assertInstanceOf('Kanboard\Event\TaskEvent', $event);
-
-        $event_data = $event->getAll();
-        $this->assertNotEmpty($event_data);
-        $this->assertEquals(1, $event_data['task_id']);
-        $this->assertEquals(1, $event_data['owner_id']);
-    }
-
-    public function testThatNoEventAreFiredWhenNoChanges()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $this->container['dispatcher']->addListener(TaskModel::EVENT_CREATE_UPDATE, array($this, 'onCreateUpdate'));
-        $this->container['dispatcher']->addListener(TaskModel::EVENT_UPDATE, array($this, 'onUpdate'));
-
-        $this->assertTrue($tm->update(array('id' => 1, 'title' => 'test')));
-
-        $this->assertEmpty($this->container['dispatcher']->getCalledListeners());
-    }
-
-    public function testChangeTitle()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $this->container['dispatcher']->addListener(TaskModel::EVENT_CREATE_UPDATE, array($this, 'onCreateUpdate'));
-        $this->container['dispatcher']->addListener(TaskModel::EVENT_UPDATE, array($this, 'onUpdate'));
-
-        $this->assertTrue($tm->update(array('id' => 1, 'title' => 'Task #1')));
-
-        $called = $this->container['dispatcher']->getCalledListeners();
-        $this->assertArrayHasKey(TaskModel::EVENT_CREATE_UPDATE.'.TaskModificationTest::onCreateUpdate', $called);
-        $this->assertArrayHasKey(TaskModel::EVENT_UPDATE.'.TaskModificationTest::onUpdate', $called);
-
-        $task = $tf->getById(1);
-        $this->assertEquals('Task #1', $task['title']);
-    }
-
-    public function testChangeAssignee()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['owner_id']);
-
-        $this->container['dispatcher']->addListener(TaskModel::EVENT_ASSIGNEE_CHANGE, array($this, 'onAssigneeChange'));
-
-        $this->assertTrue($tm->update(array('id' => 1, 'owner_id' => 1)));
-
-        $called = $this->container['dispatcher']->getCalledListeners();
-        $this->assertArrayHasKey(TaskModel::EVENT_ASSIGNEE_CHANGE.'.TaskModificationTest::onAssigneeChange', $called);
-
-        $task = $tf->getById(1);
-        $this->assertEquals(1, $task['owner_id']);
-    }
-
-    public function testChangeDescription()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('', $task['description']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'description' => 'test')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('test', $task['description']);
-    }
-
-    public function testChangeCategory()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['category_id']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'category_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(1, $task['category_id']);
-    }
-
-    public function testChangeColor()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('yellow', $task['color_id']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'color_id' => 'blue')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('blue', $task['color_id']);
-    }
-
-    public function testChangeScore()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['score']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'score' => 13)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(13, $task['score']);
-    }
-
-    public function testChangeDueDate()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['date_due']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'date_due' => '2014-11-24')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('2014-11-24', date('Y-m-d', $task['date_due']));
-
-        $this->assertTrue($tm->update(array('id' => 1, 'date_due' => time())));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(date('Y-m-d'), date('Y-m-d', $task['date_due']));
-    }
-
-    public function testChangeStartedDate()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['date_started']);
-
-        // Set only a date
-        $this->assertTrue($tm->update(array('id' => 1, 'date_started' => '2014-11-24')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('2014-11-24 '.date('H:i'), date('Y-m-d H:i', $task['date_started']));
-
-        // Set a datetime
-        $this->assertTrue($tm->update(array('id' => 1, 'date_started' => '2014-11-24 16:25')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('2014-11-24 16:25', date('Y-m-d H:i', $task['date_started']));
-
-        // Set a datetime
-        $this->assertTrue($tm->update(array('id' => 1, 'date_started' => '11/24/2014 18:25')));
-
-        $task = $tf->getById(1);
-        $this->assertEquals('2014-11-24 18:25', date('Y-m-d H:i', $task['date_started']));
-
-        // Set a timestamp
-        $this->assertTrue($tm->update(array('id' => 1, 'date_started' => time())));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(time(), $task['date_started'], '', 1);
-    }
-
-    public function testChangeTimeEstimated()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['time_estimated']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'time_estimated' => 13.3)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(13.3, $task['time_estimated']);
-    }
-
-    public function testChangeTimeSpent()
-    {
-        $p = new ProjectModel($this->container);
-        $tc = new TaskCreationModel($this->container);
-        $tm = new TaskModificationModel($this->container);
-        $tf = new TaskFinderModel($this->container);
-
-        $this->assertEquals(1, $p->create(array('name' => 'test')));
-        $this->assertEquals(1, $tc->create(array('title' => 'test', 'project_id' => 1)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(0, $task['time_spent']);
-
-        $this->assertTrue($tm->update(array('id' => 1, 'time_spent' => 13.3)));
-
-        $task = $tf->getById(1);
-        $this->assertEquals(13.3, $task['time_spent']);
-    }
-
-    public function testChangeTags()
-    {
-        $projectModel = new ProjectModel($this->container);
-        $taskCreationModel = new TaskCreationModel($this->container);
-        $taskModificationModel = new TaskModificationModel($this->container);
-        $taskTagModel = new TaskTagModel($this->container);
-
-        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
-        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1, 'tags' => array('tag1', 'tag2'))));
-        $this->assertTrue($taskModificationModel->update(array('id' => 1, 'tags' => array('tag2'))));
-
-        $tags = $taskTagModel->getList(1);
-        $this->assertEquals(array(2 => 'tag2'), $tags);
-    }
-
-    public function testRemoveAllTags()
-    {
-        $projectModel = new ProjectModel($this->container);
-        $taskCreationModel = new TaskCreationModel($this->container);
-        $taskModificationModel = new TaskModificationModel($this->container);
-        $taskTagModel = new TaskTagModel($this->container);
-
-        $this->assertEquals(1, $projectModel->create(array('name' => 'test')));
-        $this->assertEquals(1, $taskCreationModel->create(array('title' => 'test', 'project_id' => 1, 'tags' => array('tag1', 'tag2'))));
-        $this->assertTrue($taskModificationModel->update(array('id' => 1)));
-
-        $tags = $taskTagModel->getList(1);
-        $this->assertEquals(array(), $tags);
-    }
-}
diff --git a/tests/units/Model/TaskTagModelTest.php b/tests/units/Model/TaskTagModelTest.php
index 73bbeac1d..88055d5f3 100644
--- a/tests/units/Model/TaskTagModelTest.php
+++ b/tests/units/Model/TaskTagModelTest.php
@@ -22,7 +22,7 @@ class TaskTagModelTest extends Base
         $this->assertEquals(1, $tagModel->create(0, 'My tag 1'));
         $this->assertEquals(2, $tagModel->create(0, 'My tag 2'));
 
-        $this->assertTrue($taskTagModel->save(1, 1, array('My tag 1', 'My tag 2', 'My tag 3')));
+        $this->assertTrue($taskTagModel->save(1, 1, array('My tag 1', 'My tag 2', '', 'My tag 3')));
 
         $tags = $taskTagModel->getTagsByTask(1);
         $this->assertCount(3, $tags);