diagram

how an invoice gets its VAT

project:ledgertask:fix-vat-rounding

Call #2

vat_for(line, rate)

VatTotal → VatForLine

Code 1

1use crate::invoice::Line;
2
3/// VAT is rounded per line, in cents, half away from zero.
4pub fn vat_for(line: &Line, rate_percent: u32) -> i64 {
5    let gross = line.net_cents * i64::from(rate_percent);
6    (gross + 50) / 100
7}
8
9/// The invoice VAT is the sum of its rounded lines, never the rounded sum.
10pub fn vat_total(lines: &[Line], rate_percent: u32) -> i64 {
11    lines.iter().map(|line| vat_for(line, rate_percent)).sum()

How an invoice gets its VAT