PEPPOL-EN16931-R046

The same invoice, failing and fixed

Read this first. The einvoice validate command does not evaluate the Peppol BIS layer: einvoice.validate never imports einvoice.rules_peppol, so no document makes the CLI print a PEPPOL-EN16931-* id. The pair below was graded by einvoice.rules_peppol directly — the module that transcribes the Peppol asserts and backs this site's conformance matrix. It is a real verdict from real code in this repository, and it is not the verdict the CLI gives you.

The pair was found, not written: the vendored instance corpus/xrechnung-testsuite/src/test/technical-cases/cius/01.01_comprehensive_test_ubl.xml was edited one element at a time with a fixed catalogue of mechanical edits until the Peppol layer's verdict changed. The edit that did it: the PriceAmount element was deleted. It is published because that layer reported PEPPOL-EN16931-R046 for the edited document and did not report it for the untouched one.

UBL Invoice — fails

The vendored file around the change, verbatim:

<cac:Price>
  <cbc:BaseQuantity unitCode="XPP">1</cbc:BaseQuantity>
  <cac:AllowanceCharge>
    <cbc:ChargeIndicator>false</cbc:ChargeIndicator>
    <cbc:Amount currencyID="EUR">10</cbc:Amount>
    <cbc:BaseAmount currencyID="EUR">168.125</cbc:BaseAmount>
  </cac:AllowanceCharge>
</cac:Price>

UBL Invoice — passes

The same lines as 01.01_comprehensive_test_ubl.xml actually ships them — this block is the fix for the block above:

<cac:Price>
  <cbc:PriceAmount currencyID="EUR">158.125</cbc:PriceAmount>
  <cbc:BaseQuantity unitCode="XPP">1</cbc:BaseQuantity>
  <cac:AllowanceCharge>
    <cbc:ChargeIndicator>false</cbc:ChargeIndicator>
    <cbc:Amount currencyID="EUR">10</cbc:Amount>
    <cbc:BaseAmount currencyID="EUR">168.125</cbc:BaseAmount>
  </cac:AllowanceCharge>
</cac:Price>

What einvoice.rules_peppol reports for the edited invoice

{
  "element": "cac:Price/cbc:PriceAmount",
  "message": "Item net price MUST equal (Gross price - Allowance amount) when gross price is provided.",
  "rule": "PEPPOL-EN16931-R046",
  "severity": "fatal"
}

Peppol ids that layer reports for 01.01_comprehensive_test_ubl.xml untouched: none. After the edit: PEPPOL-EN16931-R046 PEPPOL-EN16931-R120.

And what einvoice validate --profile xrechnung reports for that same edited document: BR-26 BR-27. No PEPPOL-EN16931-R046 among them, which is the point of the warning above.

Two honest limits. This is an edit that provokes the rule, not the only one, and it is not a claim about how real senders break it. And it is the reverse of the fix a reader needs: the passing block is the vendored file's own content, which is what a conformant invoice looks like here.

Reproduce it yourself: take corpus/xrechnung-testsuite/src/test/technical-cases/cius/01.01_comprehensive_test_ubl.xml from this repository, apply the one edit named above, and run python3 -c "import xml.etree.ElementTree as ET, einvoice.rules_peppol as P; print(P.evaluate_ubl(ET.parse('01.01_comprehensive_test_ubl.xml').getroot()))". To see what the shipped validator says about the same file instead, paste it into the browser validator, which runs the EN 16931 / XRechnung engine locally with no upload.