XSLT 1.0 Test deviation

Question

How to check two values to see if they are different? -> Concerns the nodes Item.DeliveryDate and Item.OrigDeliveryDate.

If yes, a new node LineChangeDeliveryDate should be created with the value yes, otherwise with the value no.

XML at the moment:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<OrderResponse>
  <Interchange>    
    <Interchange_Control_Number>5637248870</Interchange_Control_Number>
  </Interchange>
  <HeaderInformation>
    <ConfirmDocNum>SO0009783-1</ConfirmDocNum>   
    <TransportDetails>
      <DeliveryMode>ROU</DeliveryMode>
    </TransportDetails>   
  </HeaderInformation>
  <LineInformation>
    <Item>      
      <DeliveryDate>2020-01-27</DeliveryDate>
      <OrigDeliveryDate>2019-12-07</OrigDeliveryDate>
    </Item>
  </LineInformation>
</OrderResponse>

XML new/correct:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<OrderResponse>
  <Interchange>    
    <Interchange_Control_Number>5637248870</Interchange_Control_Number>
  </Interchange>
  <HeaderInformation>
    <ConfirmDocNum>SO0009783-1</ConfirmDocNum>   
    <TransportDetails>
      <DeliveryMode>ROU</DeliveryMode>
    </TransportDetails>   
  </HeaderInformation>
  <LineInformation>
    <Item>      
      <DeliveryDate>2020-01-27</DeliveryDate>
      <OrigDeliveryDate>2019-12-07</OrigDeliveryDate>
      <LineChangeDeliveryDate>yes</LineChangeDeliveryDate>
    </Item>
  </LineInformation>
</OrderResponse>

Current XSLT:

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

  <xsl:key name="header_text" match="HeaderText" use="Text"/>
  <xsl:key name="line_text" match="LineText" use="concat(../LineNum, '|', Text)"/>
  <xsl:key name="allowance_charge_header" match="AllowanceOrCharge_Header" use="concat(Code, '|', Amount)"/>
  <xsl:key name="allowance_charge_line" match="AllowanceOrCharge_Line" use="concat(../LineNum, '|', Code, '|', Amount)"/>
  <xsl:key use="concat(../LineNum, '|', Text)" match="LineText" name="line_text"/>

  <!-- Identity-Template für die nicht explizit benannten Elemente -->
  <xsl:template match="@* | node()">
    <xsl:copy>
      <xsl:apply-templates select="@* | node()"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="HeaderText[generate-id() != generate-id(key('header_text', Text)[1])]" />
  <xsl:template match="LineText[generate-id() != generate-id(key('line_text', concat(../LineNum, '|', Text))[1])]" />
  <xsl:template match="AllowanceOrCharge_Header[generate-id() != generate-id(key('allowance_charge_header', concat(Code, '|', Amount))[1])]" />
  <xsl:template match="AllowanceOrCharge_Line[generate-id() != generate-id(key('allowance_charge_line', concat(../LineNum, '|', Code, '|', Amount))[1])]" />
  <xsl:template match="LineText[generate-id() != generate-id(key('line_text', concat(../LineNum, '|', Text))[1])]"/>

  <xsl:template match="Item">
    <xsl:copy>
      <LineChangeDeliveryDate>
        <xsl:choose>
          <xsl:when test="OrigDeliveryDate = DeliveryDate"/>
            <xsl:value-of select="'yes'"/>
          </xsl:when>
          <xsl:otherwise>
            <xsl:value-of select="'no'"/>
          </xsl:otherwise>
        </xsl:choose>
      </LineChangeDeliveryDate>
      <!--copy all other nodes-->
      <xsl:apply-templates select="@* | node()"/>
    </xsl:copy>
  </xsl:template>

  <!-- delete empty nodes -->
  <xsl:template match="node()|@*">
    <xsl:copy>
      <xsl:apply-templates select="node()|@*"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="*[not(@*|*|comment()|processing-instruction()) and normalize-space()='']"/>

</xsl:stylesheet>

Answer 1

In the template rule with match="Item", do

<LineChangeDeliveryDate>
  <xsl:choose>
    <xsl:when test="OrigDeliveryDate = DeliveryDate">
       <xsl:value-of select="'yes'/>
    </xsl:when>
    <xsl:otherwise>
       <xsl:value-of select="'no'/>
    </xsl:otherwise>
  </xsl:choose>
</LineChangeDeliveryDate>

This is one of many cases where the XSLT 2.0 code is much more concise:

<LineChangeDeliveryDate>
       <xsl:value-of select="if (OrigDeliveryDate = DeliveryDate) then 'yes' else 'no'"/>
</LineChangeDeliveryDate>

and in 3.0 it reduces further to

<LineChangeDeliveryDate>{
  if (OrigDeliveryDate = DeliveryDate) then 'yes' else 'no'
}</LineChangeDeliveryDate>