money/internal/parser/nlb_test.go

package parser

import "testing"

// A page as pdftotext -layout renders it: a header, transaction lines ending
// in amount and balance, and indented continuation lines carrying wrapped
// descriptions and the other side's IBAN.
// The description column sits at 15, which is what the script's
// CONTINUATION_INDENT tells us about the real layout.
const nlbPage = `                                     NLB d.d.
                              IZPISEK 001/2026

DATUM          OPIS                                    ZNESEK      STANJE

02.01.26       PLACILO S KARTICO                       -45,20    1.234,56
               LIDL SOFIA 4412                SI56 1234 5678 9012 345
05.01.26       PRILIV PLACE                         +2.500,00    3.734,56
               ACME DOO
10.01.26       PRENOS NA VARCEVALNI                   -500,00    3.234,56
15.01.26       NEGATIVNO STANJE                     -3.300,00      65,44-

Stran 1
`

func TestParseNLBText(t *testing.T) {
	txns, err := parseNLBText(nlbPage, 2)
	if err != nil {
		t.Fatal(err)
	}
	if len(txns) != 4 {
		t.Fatalf("got %d transactions, want 4: %+v", len(txns), txns)
	}

	first := txns[0]
	if first.Date != "2026-01-02" {
		t.Errorf("date = %q, want 2026-01-02", first.Date)
	}
	// The continuation line is appended to the description, and the IBAN in
	// its second column goes last so that it stays contiguous however many
	// lines it wrapped over.
	if first.Description != "PLACILO S KARTICO LIDL SOFIA 4412 SI56 1234 5678 9012 345" {
		t.Errorf("description = %q", first.Description)
	}
	if first.AmountMinor != -4520 {
		t.Errorf("amount = %d, want -4520", first.AmountMinor)
	}
	if first.BalanceMinor == nil || *first.BalanceMinor != 123456 {
		t.Errorf("balance = %v, want 123456", first.BalanceMinor)
	}

	if txns[1].AmountMinor != 250000 {
		t.Errorf("credit amount = %d, want 250000", txns[1].AmountMinor)
	}
	if txns[1].Description != "PRILIV PLACE ACME DOO" {
		t.Errorf("description = %q", txns[1].Description)
	}

	// A transaction with no continuation line gets nothing appended.
	if txns[2].Description != "PRENOS NA VARCEVALNI" {
		t.Errorf("description = %q, want no trailing account number", txns[2].Description)
	}

	// A trailing minus marks a negative balance.
	if txns[3].BalanceMinor == nil || *txns[3].BalanceMinor != -6544 {
		t.Errorf("balance = %v, want -6544", txns[3].BalanceMinor)
	}
}

// A wrapped line at the top of a page must not attach to the last transaction
// of the previous page.
func TestParseNLBPageBoundary(t *testing.T) {
	text := "02.01.26       FIRST                                      -10,00      100,00\n" +
		"\f" +
		"               STRAY CONTINUATION AT TOP OF PAGE\n" +
		"03.01.26       SECOND                                     -20,00       80,00\n" +
		"               REAL CONTINUATION\n"

	txns, err := parseNLBText(text, 2)
	if err != nil {
		t.Fatal(err)
	}
	if len(txns) != 2 {
		t.Fatalf("got %d transactions, want 2", len(txns))
	}
	if txns[0].Description != "FIRST" {
		t.Errorf("first description = %q, want FIRST (page furniture must not leak in)", txns[0].Description)
	}
	if txns[1].Description != "SECOND REAL CONTINUATION" {
		t.Errorf("second description = %q", txns[1].Description)
	}
}

// Shallowly indented lines are footers, not wrapped descriptions.
func TestParseNLBIgnoresShallowIndent(t *testing.T) {
	text := "02.01.26       FIRST                                      -10,00      100,00\n" +
		"  Stran 1 od 2\n"

	txns, err := parseNLBText(text, 2)
	if err != nil {
		t.Fatal(err)
	}
	if len(txns) != 1 || txns[0].Description != "FIRST" {
		t.Errorf("got %+v, want a single FIRST transaction", txns)
	}
}

// A date-led line without an amount and balance is a real problem, not
// something to silently drop.
func TestParseNLBRejectsMalformedLine(t *testing.T) {
	text := "02.01.26   NO AMOUNT OR BALANCE HERE\n"
	if _, err := parseNLBText(text, 2); err == nil {
		t.Error("expected an error for a transaction line with no amount")
	}
}