records: Validate length of TransactionSpecification.text field

docs/changelog.rst

@@ -18,6 +18,7 @@ v1.0.1 (UNRELEASED)
 
   - :attr:`netsgiro.records.TransactionAmountItem1.kid` (max 25 chars)
   - :attr:`netsgiro.records.TransactionAmountItem3.text` (max 40 chars)
+  - :attr:`netsgiro.records.TransactionSpecification.text` (max 40 chars)
   - :attr:`netsgiro.records.AvtaleGiroAgreement.kid` (max 25 chars)
 
   Previously the string was accepted and the record generated invalid OCR data.

netsgiro/records.py

@@ -5,7 +5,7 @@
 from typing import Iterable, List, Optional, Sequence, Tuple, Union
 
 import attr
-from attr.validators import instance_of, optional
+from attr.validators import optional
 
 import netsgiro
 from netsgiro.converters import (
@@ -626,7 +626,7 @@ class TransactionSpecification(TransactionRecord):
     column_number = attr.ib(convert=int)
     text = attr.ib(
         convert=stripped_newlines(fixed_len_str(40, str)),
-        validator=instance_of(str))
+        validator=optional(str_of_max_length(40)))
 
     RECORD_TYPE = netsgiro.RecordType.TRANSACTION_SPECIFICATION
     _PATTERNS = [

tests/test_record_writing.py

@@ -409,6 +409,21 @@ def test_transaction_specification_text_behavior(text, expected):
     assert record.text == expected
 
 
+def test_transaction_specification_raises_if_text_is_too_long():
+    with pytest.raises(ValueError) as exc_info:
+        netsgiro.records.TransactionSpecification(
+            service_code=netsgiro.ServiceCode.AVTALEGIRO,
+            transaction_type=(
+                netsgiro.TransactionType.AVTALEGIRO_WITH_BANK_NOTIFICATION),
+            transaction_number=1,
+            line_number=1,
+            column_number=1,
+            text='Fooo' * 12, # Max 40 chars
+        )
+
+    assert 'text must be at most 40 chars' in str(exc_info)
+
+
 def test_avtalegiro_agreement():
     record = netsgiro.records.AvtaleGiroAgreement(
         service_code=netsgiro.ServiceCode.AVTALEGIRO,