From 52735674708dfb5880111c15396b72894fcaa260 Mon Sep 17 00:00:00 2001
From: Aliaksei Kandratsenka <alkondratenko@gmail.com>
Date: Mon, 16 Sep 2024 19:03:58 -0400
Subject: [PATCH] [trivialre] fix past-end-of-string access in MatchSubstring

Thanks goes to MSVC's string_view asserts that check this.
---
 benchmark/trivialre.h       | 4 ++--
 benchmark/trivialre_test.cc | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/benchmark/trivialre.h b/benchmark/trivialre.h
index 4485f8b..3eba725 100644
--- a/benchmark/trivialre.h
+++ b/benchmark/trivialre.h
@@ -58,14 +58,14 @@ inline bool MatchSubstring(const Matcher& m, std::string_view str) {
   size_t sz = str.size();
   CB succeed = [](std::string_view str, bool line_start) { return true; };
   bool line_start = true;
-  for (size_t i = 0; i <= sz; i++) {
+  for (size_t i = 0; i < sz; i++) {
     if (m(str, line_start, succeed)) {
       return true;
     }
     line_start = (str[0] == '\n');
     str.remove_prefix(1);
   }
-  return false;
+  return m("", line_start, succeed);
 }
 
 Matcher CompileREOrDie(std::string_view str);
diff --git a/benchmark/trivialre_test.cc b/benchmark/trivialre_test.cc
index 161ee54..7736947 100644
--- a/benchmark/trivialre_test.cc
+++ b/benchmark/trivialre_test.cc
@@ -154,6 +154,8 @@ TEST(TrivialRETest, Runnings) {
       {"^a", "+a", "-ba", "+b\na"},
       {"a$", "+a\nb", "+ba", "+b\na"},
       {"a$\\nb", "+a\nb"},
+      {"$", "+", "+aaa"},
+      {"^$", "+", "-aaa", "+aaa\n"},
   };
 
   for (const auto& vec : cases2) {