From 7644adcaea843e53efc43778b7ac8e23d3c71214 Mon Sep 17 00:00:00 2001
From: Frank Tang <ftang@chromium.org>
Date: Tue, 6 Aug 2024 21:13:15 -0700
Subject: [PATCH] ICU-22848 Show the problem of infinity loop

Add test to show very slow creation
---
 icu4c/source/test/intltest/rbbitst.cpp | 8 ++++++++
 icu4c/source/test/intltest/rbbitst.h   | 1 +
 2 files changed, 9 insertions(+)

diff --git a/icu4c/source/test/intltest/rbbitst.cpp b/icu4c/source/test/intltest/rbbitst.cpp
index 3ccd4b5a14cc..6e54a3f02e5e 100644
--- a/icu4c/source/test/intltest/rbbitst.cpp
+++ b/icu4c/source/test/intltest/rbbitst.cpp
@@ -155,6 +155,7 @@ void RBBITest::runIndexedTest( int32_t index, UBool exec, const char* &name, cha
     TESTCASE_AUTO(TestBug22585);
     TESTCASE_AUTO(TestBug22602);
     TESTCASE_AUTO(TestBug22636);
+    TESTCASE_AUTO(TestBug22848);
 
 #if U_ENABLE_TRACING
     TESTCASE_AUTO(TestTraceCreateCharacter);
@@ -6133,6 +6134,13 @@ void RBBITest::TestBug22636() {
     assertEquals(WHERE, ec, U_ZERO_ERROR);
 }
 
+void RBBITest::TestBug22848() {
+    if (quick || logKnownIssue("ICU-22848", "Very slow case")) { return; }
+    UParseError pe {};
+    UErrorCode ec {U_ZERO_ERROR};
+    RuleBasedBreakIterator bi(u".*X..................;", pe, ec);
+}
+
 void RBBITest::TestBug22584() {
     // Creating a break iterator from a rule consisting of a very long
     // literal input string caused a stack overflow when deleting the
diff --git a/icu4c/source/test/intltest/rbbitst.h b/icu4c/source/test/intltest/rbbitst.h
index 9638caf6a277..0d69008673f7 100644
--- a/icu4c/source/test/intltest/rbbitst.h
+++ b/icu4c/source/test/intltest/rbbitst.h
@@ -106,6 +106,7 @@ class RBBITest: public IntlTest {
     void TestBug22585();
     void TestBug22602();
     void TestBug22636();
+    void TestBug22848();
 
 #if U_ENABLE_TRACING
     void TestTraceCreateCharacter();