BR-DEC-09 — E-Invoice Validation Rule & Fix

Fixture ID: overPreciseTotals · XPath: /ubl:Invoice/cac:LegalMonetaryTotal/cbc:LineExtensionAmount

1. Why This Rule Triggers (Diagnostic Message)

The allowed maximum number of decimals for the Sum of Invoice line net amounts (BT-106) is 2, but you declared 1500.001, which has 3. The rule is written against the serialised value — the schematron measures the digits after the decimal point in the XML — so a value that merely *displays* as two decimals still fails if the underlying number carries more. A sum of line amounts only carries extra decimals if the lines were summed before they were rounded. EN 16931 requires the opposite order: round each line net amount (BT-131) to two decimals first, then add.

2. How to Fix BR-DEC-09

Round declaredTotals.lineExtensionAmount to two decimals before assigning it (1500.00 here), using half-up rounding away from zero. This package exports round2() for exactly this, and it avoids the two JavaScript traps: Math.round(1.005 * 100) / 100 gives 1.00, and (2.675).toFixed(2) gives "2.67". Alternatively drop declaredTotals and let the library compute the totals, which it always rounds correctly.

3. Valid Code / Payload Example

"declaredTotals": { "lineExtensionAmount": 1500.00 }