diff --git a/tests/UnitTests/SmartyMethodsTests/AssignByRef/AssignByRefTest.php b/tests/UnitTests/SmartyMethodsTests/AssignByRef/AssignByRefTest.php
index 562eea7bf..fb78240ae 100644
--- a/tests/UnitTests/SmartyMethodsTests/AssignByRef/AssignByRefTest.php
+++ b/tests/UnitTests/SmartyMethodsTests/AssignByRef/AssignByRefTest.php
@@ -3,6 +3,8 @@
  * Smarty PHPunit tests assignByRef method
  */
 
+use Smarty\Data;
+
 /**
  * Class for assignByRef tests
  */
@@ -22,7 +24,7 @@ public function testInit()
 	/**
 	 * Test assignByRef for nullable string property
 	 */
-	public function testAssignByRefForNullableStringProperry()
+	public function testAssignByRefForNullableStringProperty()
 	{
 		$this->smarty->assignByRef('myVar', $this->testStr);
 		$this->assertEquals(null, $this->smarty->fetch('eval:{$myVar}'));
@@ -67,4 +69,188 @@ public function testAssignByRefReturnsThis()
 			$this->smarty->assignByRef('dummy', $var)->fetch('eval:{$dummy}')
 		);
 	}
+
+	/**
+	 * Test duplicate assignByRef
+	 */
+	public function testDuplicateAssignByRef()
+	{
+		$var1 = array(
+			'a' => 'A',
+		);
+		$var2= array(
+			'z' => 'Z',
+		);
+		$this->smarty->assignByRef('myVar', $var1);
+		$this->smarty->assignByRef('myVar', $var2);
+		$this->assertEquals('{"z":"Z"}', $this->smarty->fetch('eval:{$myVar|json_encode}'));
+		$var1['b'] = 'B';
+		$var2['y'] = 'Y';
+		$this->assertEquals('{"z":"Z","y":"Y"}', $this->smarty->fetch('eval:{$myVar|json_encode}'));
+	}
+
+	/**
+	 * Test assignByRef for parent scope
+	 */
+	public function testAssignByRefForParentScope()
+	{
+		$data1 = $this->smarty->createData($this->smarty);
+		$data2 = $this->smarty->createData($data1);
+		$var1 = array(
+			'a1' => 'A1'
+		);
+		$var2 = array(
+			'b1' => 'B1'
+		);
+		$var3 = array(
+			'c1' => 'C1'
+		);
+		$data1->assignByRef('var1', $var1);
+		$data2->assignByRef('var2', $var2, false, Data::SCOPE_PARENT);
+		$data2->assignByRef('var3', $var3);
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3', false));
+
+		$var1['a2'] = 'A2';
+		$var2['b2'] = 'B2';
+		$var3['c2'] = 'C2';
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3', false));
+	}
+
+	/**
+	 * Test assignByRef for root scope
+	 */
+	public function testAssignByRefForRootScope()
+	{
+		$data1 = $this->smarty->createData($this->smarty);
+		$data2 = $this->smarty->createData($data1);
+		$data3 = $this->smarty->createData($data2);
+		$var1 = array(
+			'a1' => 'A1'
+		);
+		$var2 = array(
+			'b1' => 'B1'
+		);
+		$var3 = array(
+			'c1' => 'C1'
+		);
+		$data1->assignByRef('var1', $var1);
+		$data2->assignByRef('var2', $var2, false, Data::SCOPE_PARENT);
+		$data3->assignByRef('var3', $var3, false, Data::SCOPE_ROOT);
+		$this->assertEquals($var3, $data1->getTemplateVars('var3'));
+		$this->assertEquals($var3, $data1->getTemplateVars('var3', false));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals(null, $data2->getTemplateVars('var3', false));
+
+		$var1['a2'] = 'A2';
+		$var2['b2'] = 'B2';
+		$var3['c2'] = 'C2';
+		$this->assertEquals($var3, $data1->getTemplateVars('var3'));
+		$this->assertEquals($var3, $data1->getTemplateVars('var3', false));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals(null, $data2->getTemplateVars('var3', false));
+	}
+
+	/**
+	 * Test assignByRef for TPL global scope
+	 */
+	public function testAssignByRefForGlobalScope()
+	{
+		$data1 = $this->smarty->createData($this->smarty);
+		$data2 = $this->smarty->createData($data1);
+		$data3 = $this->smarty->createData($data2);
+		$var1 = array(
+			'a1' => 'A1'
+		);
+		$var2 = array(
+			'b1' => 'B1'
+		);
+		$var3 = array(
+			'c1' => 'C1'
+		);
+		$data1->assignByRef('var1', $var1);
+		$data2->assignByRef('var2', $var2, false, Data::SCOPE_PARENT);
+		$data3->assignByRef('var3', $var3, false, Data::SCOPE_GLOBAL);
+		$this->assertEquals($var3, $this->smarty->getTemplateVars('var3'));
+		$this->assertEquals($var3, $this->smarty->getTemplateVars('var3', false));
+		$this->assertEquals($var3, $data1->getTemplateVars('var3'));
+		$this->assertEquals(null, $data1->getTemplateVars('var3', false));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals(null, $data2->getTemplateVars('var3', false));
+
+		$var1['a2'] = 'A2';
+		$var2['b2'] = 'B2';
+		$var3['c2'] = 'C2';
+		$this->assertEquals($var3, $this->smarty->getTemplateVars('var3'));
+		$this->assertEquals($var3, $this->smarty->getTemplateVars('var3', false));
+		$this->assertEquals($var3, $data1->getTemplateVars('var3'));
+		$this->assertEquals(null, $data1->getTemplateVars('var3', false));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+		$this->assertEquals($var3, $data2->getTemplateVars('var3'));
+		$this->assertEquals(null, $data2->getTemplateVars('var3', false));
+	}
+
+	/**
+	 * Test assignByRef for TPL root scope
+	 */
+	public function testAssignByRefForTplRootScope()
+	{
+		$data1 = $this->smarty->createData($this->smarty);
+		$tpl1 = $this->smarty->createTemplate('eval:{$var2|json_encode}', $data1);
+		$tpl2 = $this->smarty->createTemplate('eval:{$var2|json_encode}', $tpl1);
+		$data2 = $tpl2->createData($tpl2);
+		$var1 = array(
+			'a1' => 'A1'
+		);
+		$var2 = array(
+			'b1' => 'B1'
+		);
+		$var3 = array(
+			'c1' => 'C1'
+		);
+		$data1->assignByRef('var1', $var1);
+		$data2->assignByRef('var2', $var2, false, Data::SCOPE_TPL_ROOT);
+		$this->assertEquals('{"b1":"B1"}', $tpl1->fetch());
+		$this->assertEquals($var2, $tpl1->getTemplateVars('var2'));
+		$this->assertEquals($var2, $tpl1->getTemplateVars('var2', false));
+		$this->assertEquals(null, $data1->getTemplateVars('var2'));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+
+		$var1['a2'] = 'A2';
+		$var2['b2'] = 'B2';
+		$this->assertEquals($var2, $tpl1->getTemplateVars('var2'));
+		$this->assertEquals($var2, $tpl1->getTemplateVars('var2', false));
+		$this->assertEquals(null, $data1->getTemplateVars('var2'));
+		$this->assertEquals($var1, $data2->getTemplateVars('var1'));
+		$this->assertEquals(null, $data2->getTemplateVars('var1', false));
+		$this->assertEquals($var2, $data2->getTemplateVars('var2'));
+		$this->assertEquals(null, $data2->getTemplateVars('var2', false));
+	}
 }