ZF-8419: _isPartialRendering in Zend_Form_Element can break Zend_Form_Element_File::render()
We have just updated to 1.9.6 to find that our file upload forms no longer work.
This is due to a bug that was introduced when ZF-7404 was fixed.
This causes the render() method of Zend_Form_Element_File to be called from renderViewHelper() and renderErrors(). Unfortunately, Zend_Form_Element_File::render() throws an exception, as there are no file decorators.
We have worked around the problem locally by returning early from Zend_Form_Element_File::render() if $this->_isPartialRendering is true, but this doesn't seem ideal. Instead of _isPartialRendering, I would recommend that Zend_Form_Element introduces partialRender(), with an empty implementation by default. Zend_Form_Element_Hash could then implement partialRender to fix ZF-7404.