TYPO3.Fluid

Currently it is not possible to group by an object.

Example :

class Foo {
    /** @return array<Bar> */
    public function getBars();
}

class Bar {
    /** @return Baz */
    public function getBaz();
}

class Baz {
}

Now, lets loop over them using the Baz objects as key.

<f:groupedFor each="{foo.bars}" as="bars" groupBy="baz" groupKey="baz">
    {baz.title}:
    <ul>
        <f:for each="{bars}" as="bar">
            <li>{bar.name}</li>
        </f:for>
    </ul>
</f:groupedFor>

I expected output from this loop, something like

    A crazy baz title:
    <ul>
            <li>A named bar</li>
            <li>Another named bar</li>
    </ul>
    Second crazy baz title:
    <ul>
            <li>A further named bar</li>
            <li>And yet another named bar</li>
            <li>The last named bar</li>
    </ul>

I got nothing. So I dug into this and created the attached patch, enabling the expected behavior.