From 22122f390192ffaa67b8e62fdf7ac7aa630956c0 Mon Sep 17 00:00:00 2001
From: gabime <gmelman1@gmail.com>
Date: Sat, 29 Mar 2025 13:58:40 +0300
Subject: [PATCH] Merge  PR #3366 from 1.x (Fix zformatter on Apple and
 POSIX.1-2024 conforming platform)

---
 src/details/os_unix.cpp          |  6 ++++--
 tests/test_pattern_formatter.cpp | 26 ++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/details/os_unix.cpp b/src/details/os_unix.cpp
index 5149828b..5c5828f3 100644
--- a/src/details/os_unix.cpp
+++ b/src/details/os_unix.cpp
@@ -129,8 +129,10 @@ size_t filesize(FILE *f) {
 
 // Return utc offset in minutes or throw spdlog_ex on failure
 int utc_minutes_offset(const std::tm &tm) {
-#if defined(sun) || defined(__sun) || defined(_AIX) || (defined(__NEWLIB__) && !defined(__TM_GMTOFF)) || \
-    (!defined(_BSD_SOURCE) && !defined(_GNU_SOURCE))
+    #if defined(sun) || defined(__sun) || defined(_AIX) || \
+       (defined(__NEWLIB__) && !defined(__TM_GMTOFF)) ||  \
+       (!defined(__APPLE__) && !defined(_BSD_SOURCE) && !defined(_GNU_SOURCE) && \
+       (!defined(_POSIX_VERSION) || (_POSIX_VERSION < 202405L)))
     // 'tm_gmtoff' field is BSD extension and it's missing on SunOS/Solaris
     struct helper {
         static long int calculate_gmt_offset(const std::tm &localtm = details::os::localtime(),
diff --git a/tests/test_pattern_formatter.cpp b/tests/test_pattern_formatter.cpp
index 85f2114b..bcc61f18 100644
--- a/tests/test_pattern_formatter.cpp
+++ b/tests/test_pattern_formatter.cpp
@@ -2,6 +2,8 @@
 #include "spdlog/sinks/ostream_sink.h"
 #include "test_sink.h"
 
+#include <chrono>
+
 using spdlog::memory_buf_t;
 
 // log to str and return it
@@ -18,6 +20,21 @@ static std::string log_to_str(const std::string &msg, const Args &...args) {
     return oss.str();
 }
 
+// log to str and return it with time
+template <typename... Args>
+static std::string log_to_str_with_time(spdlog::log_clock::time_point log_time, const std::string &msg, const Args &...args) {
+    std::ostringstream oss;
+    auto oss_sink = std::make_shared<spdlog::sinks::ostream_sink_mt>(oss);
+    spdlog::logger oss_logger("pattern_tester", oss_sink);
+    oss_logger.set_level(spdlog::level::info);
+
+    oss_logger.set_formatter(
+        std::unique_ptr<spdlog::formatter>(new spdlog::pattern_formatter(args...)));
+
+    oss_logger.log(log_time, {}, spdlog::level::info, msg);
+    return oss.str();
+}
+
 TEST_CASE("custom eol", "[pattern_formatter]") {
     std::string msg = "Hello custom eol test";
     std::string eol = ";)";
@@ -52,6 +69,15 @@ TEST_CASE("date MM/DD/YY ", "[pattern_formatter]") {
     REQUIRE(log_to_str("Some message", "%D %v", spdlog::pattern_time_type::local, "\n") == oss.str());
 }
 
+TEST_CASE("GMT offset ", "[pattern_formatter]") {
+    using namespace std::chrono_literals;
+    const auto now = std::chrono::system_clock::now();
+    const auto yesterday = now - 24h;
+
+    REQUIRE(log_to_str_with_time(yesterday, "Some message", "%z", spdlog::pattern_time_type::utc, "\n") ==
+            "+00:00\n");
+}
+
 TEST_CASE("color range test1", "[pattern_formatter]") {
     auto formatter = std::make_shared<spdlog::pattern_formatter>("%^%v%$", spdlog::pattern_time_type::local, "\n");