#David Carlisle <davidc@nag.co.uk> plays nifty tricks with xsl:key

from Xml.Xslt import test_harness

sheet_1 = """<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                version="1.0"
                >

<xsl:output method="xml" indent="yes"/>

<xsl:key name="items-by-itemid"
         match="item"
         use="concat(generate-id(..), @itemid)"
/>

<xsl:template match="itemlist">
 <xsl:variable name="x" select="generate-id(.)"/>
  <xsl:for-each select="item[count(. |
                                   key('items-by-itemid',
                                       concat($x, @itemid))[1]) = 1]">

    <xsl:sort select="@itemid" />
    <tr>
      <td><xsl:value-of select="@itemid"/></td>
      <td><xsl:value-of select="sum(key('items-by-itemid',
                                          concat($x, @itemid))/@units)"/></td>
    </tr>
  </xsl:for-each>
</xsl:template>

<xsl:template match='text()'/>

</xsl:stylesheet>"""

source_1 = """<x>
  <itemlist>
	<item itemid="Z101" units="1"/>
	<item itemid="Z102" units="2"/>
	<item itemid="Z101" units="4"/>
  </itemlist>

  <itemlist>
	<item itemid="y101" units="1"/>
	<item itemid="y102" units="2"/>
	<item itemid="y102" units="3"/>
	<item itemid="y101" units="4"/>
	<item itemid="y101" units="5"/>
  </itemlist>

</x>"""

expected_1 = """<?xml version="1.0" encoding="UTF-8"?>
<tr>
  <td>Z101</td>
  <td>5</td>
</tr>
<tr>
  <td>Z102</td>
  <td>2</td>
</tr>
<tr>
  <td>y101</td>
  <td>10</td>
</tr>
<tr>
  <td>y102</td>
  <td>5</td>
</tr>"""

def Test(tester):
    source = test_harness.FileInfo(string=source_1)
    sheet = test_harness.FileInfo(string=sheet_1)
    test_harness.XsltTest(tester, source, [sheet], expected_1)
    return