From 01cac5f357433d19981f048abfc8dc618f6c5736 Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Wed, 8 Jul 2026 17:51:59 +0100
Subject: [PATCH] fix(pe/cui): allow a letter as the optional check digit

---
 src/pe/cui.spec.ts | 6 ++++++
 src/pe/cui.ts      | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/pe/cui.spec.ts b/src/pe/cui.spec.ts
index edd7d8ce..aabb650f 100644
--- a/src/pe/cui.spec.ts
+++ b/src/pe/cui.spec.ts
@@ -14,6 +14,12 @@ describe('pe/cui', () => {
     expect(result.isValid && result.compact).toEqual('101174102');
   });
 
+  it('validate:10812543-H', () => {
+    const result = validate('10812543-H');
+
+    expect(result.isValid && result.compact).toEqual('10812543H');
+  });
+
   it('validate:1011741', () => {
     const result = validate('1011741');
 
diff --git a/src/pe/cui.ts b/src/pe/cui.ts
index f3639051..43ae5b50 100644
--- a/src/pe/cui.ts
+++ b/src/pe/cui.ts
@@ -54,7 +54,7 @@ const impl: Validator = {
     if (value.length !== 8 && value.length !== 9) {
       return { isValid: false, error: new exceptions.InvalidLength() };
     }
-    if (!strings.isdigits(value)) {
+    if (!strings.isdigits(value.substr(0, 8))) {
       return { isValid: false, error: new exceptions.InvalidFormat() };
     }