XSL prevent new whitespace/line return in copy

In my text-based XML corpus I have a lot of markup of different data (using TEI schema). As part of the process of transforming these documents into a PDF, I am preprocessing it into a simplified file for xsl:fo to transform. In that preprocessing I am assigning footnote numbers by finding the markup and adding <sup>incremented integer</sup>.

A line like this:

<p>
  <seg>
    <date type="deposition_date">Item anno et die quo supra</date>. <persName>P Lapassa Senior</persName> testis iuratus idem per omnia quod predictus <persName>Hugo de Mamiros</persName>.
  </seg>
</p>

Processed with this:

<xsl:template match="tei:date">
    <xsl:copy>
        <xsl:apply-templates select="@*|node()"/>
    </xsl:copy><sup><xsl:number count="date[@type='deposition_date'" from="tei:p" format="1" level="any"/></sup>
</xsl:template>

Outputs this (note the new line for <sup>):

<p>
  <seg>
    <date type="deposition_date">Item anno et die quo supra</date>
    <sup>1</sup>. <persName>P Lapassa Senior</persName> testis iuratus idem per omnia quod predictus <persName>Hugo de Mamiros</persName>.
  </seg>
</p>

The result is that when xsl:fo processes the <sup> into superscript, there is a space between the target and the superscript, like so:

Item anno et die quo supra ¹. P Lapassa Senior testis iuratus idem per omnia quod predictus Hugo de Mamiros.

Is there a manner to stop new lines/carriage returns from being introduced in the copy process?

Additional info: I've got <xsl:strip-space elements="*"/> in the xsl document. Tested against Saxon PE 9.6 and HE 9.8.

Thanks in advance.

Solution

If you want indented output, but there are some elements with mixed content where it's not safe to let the system insert whitespace before or after contained elements, you can control this with the new XSLT 3.0 suppress-indentation property. For example, <xsl:output indent='yes' suppress-indentation='p'/> will stop any whitespace being inserted within the content of a p element.