mapnik/tests/visual_tests/styles/marker-svg-empty-g-element.xml

<Map srs="+init=epsg:4326">

    <Style name="svg">
        <Rule>
            <MarkersSymbolizer file="../../data/svg/place-of-worship-24.svg"/>
        </Rule>
    </Style>

    <Layer name="svg" srs="+init=epsg:4326">
        <StyleName>svg</StyleName>
        <Datasource>
            <Parameter name="type">csv</Parameter>
            <Parameter name="inline">
x,y
2.5,2.5
            </Parameter>
        </Datasource>
    </Layer>

    <!-- points to frame data view -->

    <Style name="frame">
        <Rule>
            <PointSymbolizer />
            <DebugSymbolizer />
        </Rule>
    </Style>

    <Layer name="frame" srs="+init=epsg:4326">
        <StyleName>frame</StyleName>
        <Datasource>
            <Parameter name="type">csv</Parameter>
            <Parameter name="inline">
x,y
0,0
5,0
0,5
5,5
            </Parameter>
        </Datasource>
    </Layer>
    
</Map>