[BUG] templates:each produces superfluous empty element

[yamahito]

Expected behaviour

@data-template="templates:each" on an e.g. li element produces one li for each member of a sequence given by @data-template-from.

Actual behaviour

An extra, superfluous, empty li element is inserted before (or sometimes around, see below) the expected results. Attributes are preserved.

Reproduction steps

This is an old, established bug: see for example https://github.com/HistoryAtState/hsg-shell/issues/37.

In trying to replicate the behaviour I am seeing on our live server, I have instead managed to produce the superfluous li around the expected result, instead of before it; perhaps something to do with html vs xml outputs?:

xquery version "3.1";

import module namespace templates="http://exist-db.org/xquery/templates";

declare namespace test="example.com/test";

declare function test:li($node, $model) {
    $model?li
};

let $config := map{
    $templates:CONFIG_FN_RESOLVER : function($functionName as xs:string, $arity as xs:int) {
        try {
            function-lookup(xs:QName($functionName), $arity)
        } catch * {
            ()
        }
    },
    $templates:CONFIG_PARAM_RESOLVER : map{}
}

let $model := map {
    $templates:CONFIGURATION : $config,
    "ul": ("one", "two", "five")
}

let $node :=
    <ul>
        <li class="ArthurianCount" data-template="templates:each" data-template-from="ul" data-template-to="li">
            <span data-template="test:li"/>
        </li>
    </ul>

return templates:process($node, $model)

Please provide the following

• exist-db version: 6.1.0-SNAPSHOT
• templating version: 1.0.4

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[yamahito]

So if I choose 'direct output' in exide and inspect the result window, I see the list item as a first sibling rather than a surrounding li:

So, I suspect the exact nature of the bug was being obfusticated by browsers' HTML parsing, and the bug is actually that the element is duplicated as both parent and children.

[yamahito]

🤦‍♂️ never mind, just spotted that http://exist-db.org/xquery/templates should be http://exist-db.org/xquery/html-templating