Interestingly, we should be in the right subtree as this modified example is supposed to demonstrate (we're getting the correct numbers under each index-entry-term, just the terms are incorrect in all but the first case):

\startxmlsetups xml:test
                \xmlsetsetup{#1}{*}{-}
                \xmlsetsetup{#1}{index}{xml:*}
                \xmlsetsetup{#1}{index-entry}{xml:index-entry}
                %\xmlsetsetup{#1}{index-entry}{xml:index-entry-2}
                \xmlsetsetup{#1}{term}{xml:index-entry-term}
                \xmlsetsetup{#1}{nav-pointer-group}{xml:*}
                \xmlsetsetup{#1}{nav-pointer}{xml:nav-pointer}
                \xmlsetsetup{#1}{nav-pointer/ext-link}{xml:nav-pointer-link}
\stopxmlsetups

\xmlregisterdocumentsetup{test}{xml:test}

% Index

\startxmlsetups xml:book-back
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:index
  \startsectionlevel[title={\xmlfilter{#1}{/index-title-group/title/command(xml:index-title)}},]
                \xmlflush{#1}
  \stopsectionlevel
\stopxmlsetups

\startxmlsetups xml:index-title
                \xmlflush{#1}
\stopxmlsetups

\definedescription[indexentry]
                [alternative=top,
                headstyle=normal,
    headcommand=\hskip-1cm,
                margin=1cm,
                inbetween=,
                ]

\startxmlsetups xml:index-entry
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:index-entry-2
    \xmlfilter{#1}{/term/command(xml:index-entry-term)}%
    \xmlverbatim{#1}
\stopxmlsetups

\startxmlsetups xml:index-entry-term
                \indexentry{\xmlflush{#1}}
\stopxmlsetups

\startxmlsetups xml:nav-pointer-group
                \xmlconcat{#1}{/nav-pointer}{, }
\stopxmlsetups

\startxmlsetups xml:nav-pointer
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:nav-pointer-link
                \xmlflush{#1}
\stopxmlsetups

\startbuffer[test]
<?xml version="1.0" encoding="UTF-8"?>
<index>
      <index-title-group>
        <title>Index</title>
      </index-title-group>
      <index-entry>
        <term>First</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>1</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>2</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>3</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
      <index-entry>
        <term>Second</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>4</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
      <index-entry>
        <term>Third</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>5</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>6</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>7</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
</index>
\stopbuffer


\starttext

\xmlprocessbuffer{test}{test}{}

\stoptext

Von: denis.maier@unibe.ch <denis.maier@unibe.ch>
Gesendet: Montag, 24. Juli 2023 13:38
An: ntg-context@ntg.nl
Betreff: [NTG-context] xml: matches always child of other element

Hi,

I must be missing something obvious, but in this example the pattern for <term> always matches the first element, not the one under the current <index-entry>.
Interestingly, using xml:index-entry-2 instead of the normal version matches correctly... Any hints what is going off the rails here?

Best,
Denis

\startxmlsetups xml:test
                \xmlsetsetup{#1}{*}{-}
                \xmlsetsetup{#1}{index}{xml:*}
                \xmlsetsetup{#1}{index-entry}{xml:index-entry}
                %\xmlsetsetup{#1}{index-entry}{xml:index-entry-2}
                \xmlsetsetup{#1}{term}{xml:index-entry-term}
                \xmlsetsetup{#1}{nav-pointer-group}{xml:*}
                \xmlsetsetup{#1}{nav-pointer}{xml:nav-pointer}
                \xmlsetsetup{#1}{nav-pointer/ext-link}{xml:nav-pointer-link}
\stopxmlsetups

\xmlregisterdocumentsetup{test}{xml:test}

% Index

\startxmlsetups xml:book-back
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:index
  \startsectionlevel[title={\xmlfilter{#1}{/index-title-group/title/command(xml:index-title)}},]
                \xmlflush{#1}
  \stopsectionlevel
\stopxmlsetups

\startxmlsetups xml:index-title
                \xmlflush{#1}
\stopxmlsetups

\definedescription[indexentry]
                [alternative=top,
                headstyle=normal,
    headcommand=\hskip-1cm,
                margin=1cm,
                inbetween=,
                ]

\startxmlsetups xml:index-entry
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:index-entry-2
    \xmlfilter{#1}{/term/command(xml:index-entry-term)}%
    \xmlverbatim{#1}
\stopxmlsetups

\startxmlsetups xml:index-entry-term
                \indexentry{\xmlflush{#1}}
\stopxmlsetups

\startxmlsetups xml:nav-pointer-group
                \xmlconcat{#1}{/nav-pointer}{, }
\stopxmlsetups

\startxmlsetups xml:nav-pointer
                \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:nav-pointer-link
                \xmlflush{#1}
\stopxmlsetups

\startbuffer[test]
<?xml version="1.0" encoding="UTF-8"?>
<index>
      <index-title-group>
        <title>Index</title>
      </index-title-group>
      <index-entry>
        <term>First</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>1</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>2</ext-link>
          </nav-pointer>
          <nav-pointer>
            <ext-link>3</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
      <index-entry>
        <term>Second</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>1</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
      <index-entry>
        <term>Third</term>
        <nav-pointer-group>
          <nav-pointer>
            <ext-link>1</ext-link>
          </nav-pointer>
        </nav-pointer-group>
      </index-entry>
</index>
\stopbuffer

\starttext

\xmlprocessbuffer{test}{test}{}

\stoptext