Apply multiple templates in XSLT 1.0 like XSLT 2.0's <next-match>

For the (contrived) HTML example below:

<div>
  <p>lorem <a href="lorem.html" target="_blank">ipsum</a></p>
  <a href="foo.html" target="top">foo</a>
  <p><img src="foo.jpg" class="bar"/></p>
  <img src="bar.jpg" class="bar"/>
</div>

I'm trying to write an XSLT 1.0 transform which:

whitelists top-level <p>
whitelists href attribute for <a>
whitelists src attribute for <img>
wraps top-level <a> and <img> in <p>...</p>

Ideally this would be done is a way that allows adding more elements and attributes.

Expected output:

<div>
  <p>lorem <a href="lorem.html">ipsum</a></p>
  <p><a href="foo.html">foo</a></p>
  <p><img src="foo.jpg"/></p>
  <p><img src="bar.jpg"/></p>
</div>

The following XSLT 2.0 works thanks to <xsl:next-match>:

Fiddle: https://xsltfiddle.liberty-development.net/6r5Gh3p:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:output omit-xml-declaration="yes" indent="yes"/>

  <xsl:template match="/div">
    <xsl:copy>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- whitelist <p> as top-level element -->

  <xsl:template match="/div/p">
    <xsl:copy>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- coerce top-level <img> and <a> as children <p> -->

  <xsl:template match="/div/img|/div/a">
    <p><xsl:next-match/></p>
  </xsl:template>

  <!-- whitelist href attribute for <a> -->

  <xsl:template match="a">
    <xsl:copy>
      <xsl:copy-of select="@href"/>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- whitelist src attribute for <img> -->

  <xsl:template match="img">
    <xsl:copy>
      <xsl:copy-of select="@src"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

In XSLT 1.0 there is no <next-match> and using the template below only matches once, so <a> and <img> do get wrapped in <p> but their attributes don't get whitelisted:

Fiddle: https://xsltfiddle.liberty-development.net/94rmq6r

  <xsl:template match="/div/img|/div/a">
    <p>
      <xsl:copy><xsl:apply-templates/></xsl:copy>
    </p>
  </xsl:template>

Output:

<div>
  <p>lorem <a href="lorem.html">ipsum</a></p>
  <p><a>foo</a></p>
  <p><img src="foo.jpg"/></p>
  <p><img/></p>
</div>

How can this be accomplished in XSLT 1.0?

Solution

You could make use of xsl:import and xsl:apply-imports here.

You would start off by putting your "whitelist" templates in a separate XSLT file (call it "Whitelist.xslt")

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:output omit-xml-declaration="yes" indent="yes"/>

  <!-- whitelist <p> as top-level element -->
  <xsl:template match="/div/p">
    <xsl:copy>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- whitelist href attribute for <a> -->
  <xsl:template match="a">
    <xsl:copy>
      <xsl:copy-of select="@href"/>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- whitelist src attribute for <img> -->
  <xsl:template match="img">
    <xsl:copy>
      <xsl:copy-of select="@src"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

Then, your main XSLT could import this, and use xsl:apply-imports wherever you had used xsl:next-match

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:import href="Whitelist.xslt" />

  <xsl:output omit-xml-declaration="yes" indent="yes"/>

  <xsl:template match="/div">
    <xsl:copy>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <!-- coerce top-level <img> and <a> as children <p> -->
  <xsl:template match="/div/img|/div/a">
    <p><xsl:apply-imports/></p>
  </xsl:template>
</xsl:stylesheet>

With an imported stylesheet, the templates inside have lower priority than the ones in the main stylesheet, so the main template will always be matched first.

EDIT: As an aside... I know your example is contrived, but for this particular case, you can re-write it without the next matches or applying imports, like so...

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output omit-xml-declaration="yes" indent="yes"/>

  <xsl:template match="/div|/div/p">
    <xsl:copy>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="/div/img|/div/a">
    <p>
      <xsl:copy>
        <xsl:apply-templates select="@*|node()" />
      </xsl:copy>
    </p>
  </xsl:template>

  <xsl:template match="a|img">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()" />
    </xsl:copy>
  </xsl:template>

  <xsl:template match="a/@href|img/@src">
    <xsl:copy />
  </xsl:template>

  <xsl:template match="@*" />
</xsl:stylesheet>