From 6a3b40524c63f54116e5d77fa16771816ec2b263 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@meta.com>
Date: Fri, 4 Jul 2025 09:50:55 -0700
Subject: [PATCH] Use actual example code and move safe_fopen to os-test

---
 test/format-test.cc | 18 +++++++-----------
 test/os-test.cc     | 13 ++++++++++++-
 test/util.h         | 11 -----------
 3 files changed, 19 insertions(+), 23 deletions(-)

diff --git a/test/format-test.cc b/test/format-test.cc
index 322b2794..6697dc17 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1809,19 +1809,15 @@ TEST(format_test, format_examples) {
   fmt::format_to(std::back_inserter(out), "The answer is {}.", 42);
   EXPECT_EQ("The answer is 42.", to_string(out));
 
-  const char* filename = "nonexistent";
-  FILE* ftest = safe_fopen(filename, "r");
-  if (ftest) fclose(ftest);
-  int error_code = errno;
-  EXPECT_TRUE(ftest == nullptr);
-  EXPECT_SYSTEM_ERROR(
+  EXPECT_THROW(
       {
-        FILE* f = safe_fopen(filename, "r");
-        if (!f)
-          throw fmt::system_error(errno, "Cannot open file '{}'", filename);
-        fclose(f);
+        const char* filename = "madeup";
+        FILE* file = fopen(filename, "r");
+        if (!file)
+          throw fmt::system_error(errno, "cannot open file '{}'", filename);
+        fclose(file);
       },
-      error_code, "Cannot open file 'nonexistent'");
+      std::system_error);
 
   EXPECT_EQ("First, thou shalt count to three",
             fmt::format("First, thou shalt count to {0}", "three"));
diff --git a/test/os-test.cc b/test/os-test.cc
index db861e55..f3f39d24 100644
--- a/test/os-test.cc
+++ b/test/os-test.cc
@@ -19,10 +19,21 @@ using fmt::buffered_file;
 using testing::HasSubstr;
 using wstring_view = fmt::basic_string_view<wchar_t>;
 
-static std::string uniq_file_name(unsigned line_number) {
+static auto uniq_file_name(unsigned line_number) -> std::string {
   return "test-file" + std::to_string(line_number);
 }
 
+auto safe_fopen(const char* filename, const char* mode) -> FILE* {
+#if defined(_WIN32) && !defined(__MINGW32__)
+  // Fix MSVC warning about "unsafe" fopen.
+  FILE* f = nullptr;
+  errno = fopen_s(&f, filename, mode);
+  return f;
+#else
+  return std::fopen(filename, mode);
+#endif
+}
+
 #ifdef _WIN32
 
 #  include <windows.h>
diff --git a/test/util.h b/test/util.h
index 803cdeea..1f2916a9 100644
--- a/test/util.h
+++ b/test/util.h
@@ -31,17 +31,6 @@ extern const char* const file_content;
 // Opens a buffered file for reading.
 auto open_buffered_file(FILE** fp = nullptr) -> fmt::buffered_file;
 
-inline auto safe_fopen(const char* filename, const char* mode) -> FILE* {
-#if defined(_WIN32) && !defined(__MINGW32__)
-  // Fix MSVC warning about "unsafe" fopen.
-  FILE* f = nullptr;
-  errno = fopen_s(&f, filename, mode);
-  return f;
-#else
-  return std::fopen(filename, mode);
-#endif
-}
-
 template <typename Char> class basic_test_string {
  private:
   std::basic_string<Char> value_;