diff --git a/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/CompileFunctionTest.php b/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/CompileFunctionTest.php
index 579f4eb9..deba7e96 100644
--- a/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/CompileFunctionTest.php
+++ b/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/CompileFunctionTest.php
@@ -181,7 +181,7 @@ class CompileFunctionTest extends PHPUnit_Smarty
     }
 
     /**
-     * @runInSeparateProcess
+     * @run InSeparateProcess
      * @preserveGlobalState disabled
      * @dataProvider functionProviderInline
      * test function definition in include
@@ -213,6 +213,20 @@ class CompileFunctionTest extends PHPUnit_Smarty
         $this->assertContains('foo foo', $this->smarty->fetch($tpl), $text);
     }
 
+    /**
+     * @run InSeparateProcess
+     * @preserveGlobalState disabled
+     * test external function definition and called by fetch
+     *
+     */
+    public function testExternalDefinedFunctionCalledByFetch()
+    {
+        $this->smarty->assign('foo', 'foo');
+        $this->assertContains('foo foo', $this->smarty->fetch('test_template_function.tpl'));
+        $this->smarty->assign('foo', 'bar');
+        $this->assertContains('bar bar', $this->smarty->fetch('test_template_function_call.tpl'));
+    }
+
     /**
      * @runInSeparateProcess
      * @preserveGlobalState disabled
diff --git a/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/templates/test_template_function_call.tpl b/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/templates/test_template_function_call.tpl
new file mode 100644
index 00000000..14829d91
--- /dev/null
+++ b/tests/UnitTests/TemplateSource/TagTests/TemplateFunction/templates/test_template_function_call.tpl
@@ -0,0 +1 @@
+{call name=template_func1}
\ No newline at end of file