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Problem of using ancestor axis in XPath predicate

Using this source document:

<?xml version="1.0" encoding="UTF-8"?>
<Root>
  <Element1 id="UniqueId1">
    <SubElement1/>
    <SubElement2>
      <LeafElement1/>
      <LeafElement1/>
    </SubElement2>
  </Element1>
  <Element2 id="UniqueId2" AttributeToCheck="true">
    <SubElement1>
      <LeafElement1/>
      <LeafElement1/>
    </SubElement1>
  </Element2> 
</Root>

I want to add the foo = "bar" attribute to elements that are both:

  • Have items with similar names.
  • Any ancestor with AttributeToCheck attribute

This should be the result of:

<?xml version="1.0"?>
<Root>
  <Element1 id="UniqueId1">
    <SubElement1/>
    <SubElement2>
      <LeafElement1/>
      <LeafElement1/>
    </SubElement2>
  </Element1>
  <Element2 id="UniqueId2" AttributeToCheck="true">
    <SubElement1>
      <LeafElement1 foo="bar"/>
      <LeafElement1 foo="bar"/>
    </SubElement1>
  </Element2>
</Root>

This is my sheet so far. It adds attribute elements matching condition 1, but does not account for condition 2.

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" version="1.0" indent="yes"/>

  <xsl:template match="* | @*">
    <xsl:copy>
      <xsl:apply-templates select="* | @*"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="*[count(../*[name(.) = name(current())]) > 1]">
    <xsl:copy>
      <xsl:attribute name="foo">bar</xsl:attribute>
      <xsl:apply-templates select="* | @*"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

Invalid output:

<?xml version="1.0"?>
<Root>
  <Element1 id="UniqueId1">
    <SubElement1/>
    <SubElement2>
      <LeafElement1 foo="bar"/> (incorrect)
      <LeafElement1 foo="bar"/> (incorrect)
    </SubElement2>
  </Element1>
  <Element2 id="UniqueId2" AttributeToCheck="true">
    <SubElement1>
      <LeafElement1 foo="bar"/> (correct)
      <LeafElement1 foo="bar"/> (correct)
    </SubElement1>
  </Element2>
</Root>

Since the second template already correctly matches elements that have siblings of the same name, it should be easy to use the XPath ancestor axis to exclude elements without AttributeToCheck ancestors. I added another predicate to the second pattern.

<xsl:template match="*[ancestor::*[@AttributeToCheck]][count(../*[name(.) = name(current())]) > 1]">

, , , - . , node.

<xsl:template match="*[count(ancestor::*[@AttributeToCheck]) > 0][count(../*[name(.) = name(current())]) > 1]">

, , . , , AttributeToCheck, . :

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" version="1.0" indent="yes"/>

  <xsl:template match="* | @*">
    <xsl:copy>
      <xsl:apply-templates select="* | @*"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="*[count(../*[name(.) = name(current())]) > 1]">
    <xsl:copy>
      <xsl:attribute name="foo">bar</xsl:attribute>
      <xsl:attribute name="AncestorCount">
        <xsl:value-of select="count(ancestor::*[@AttributeToCheck])"/>
      </xsl:attribute>
      <xsl:attribute name="AncestorName">
        <xsl:value-of select="name(ancestor::*[@AttributeToCheck])"/>
      </xsl:attribute>
      <xsl:apply-templates select="* | @*"/>
    </xsl:copy>
  </xsl:template>

</xsl:stylesheet>

:

<?xml version="1.0"?>
<Root>
  <Element1 id="UniqueId1">
    <SubElement1/>
    <SubElement2>
      <LeafElement1 foo="bar" AncestorCount="0" AncestorName=""/>
      <LeafElement1 foo="bar" AncestorCount="0" AncestorName=""/>
    </SubElement2>
  </Element1>
  <Element2 id="UniqueId2" AttributeToCheck="true">
    <SubElement1>
      <LeafElement1 foo="bar" AncestorCount="1" AncestorName="Element2"/>
      <LeafElement1 foo="bar" AncestorCount="1" AncestorName="Element2"/>
    </SubElement1>
  </Element2>
</Root>

: XPath *[ancestor::*[@AttributeToCheck]][count(../*[name(.) = name(current())]) > 1] , 1 2? XPath ?

+3
3

, XSL-, XSLT. ( count(ancestor::*[@AttributeToCheck]) > 0 , ancestor::*[@AttributeToCheck='true'], .)

, , XmlStarlet:

<xsl:template match="*[ancestor::*[@AttributeToCheck='true'] and count(../*[name(.)=name(current())]) > 1]">

§ 2.1 §3.4 XPath 1.0 ( ) .

. , @AttributeToCheck .

+1

( ):

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" version="1.0" indent="yes"/>

  <xsl:template match="* | @*">
    <xsl:copy>
      <xsl:if test="count(../*[name(current()) = name()]) > 1 and ancestor::*[@AttributeToCheck='true']">
        <xsl:attribute name="foo">bar</xsl:attribute>      
      </xsl:if>
      <xsl:apply-templates select="* | @*"/>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>
+3

count(), node -set false. , , :

<xsl:stylesheet 
  version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>
  <!-- modified identity transform -->
  <xsl:template match="node() | @*">
    <xsl:copy>
      <!-- check both your conditions -->
      <xsl:if test="
        ancestor::*[@AttributeToCheck = 'true']
        and
        (preceding-sibling::* | following-sibling::*)[name() = name(current())]
      ">
        <xsl:attribute name="foo">bar</xsl:attribute>
      </xsl:if>
      <xsl:apply-templates select="node() | @*" />
    </xsl:copy>
  </xsl:template>

</xsl:stylesheet>
+1

Source: https://habr.com/ru/post/1724295/

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