From d7592ad8bfa41eda239497f672ae8dc7bda00a4b Mon Sep 17 00:00:00 2001
From: Patrick Geltinger <patlkli@patlkli.org>
Date: Fri, 12 May 2023 00:25:21 +0200
Subject: [PATCH] Fix time_point formatting for durations with certain ratios
 (#3430)

* Fix time_point formatting

* Add timestamps_ratios tests
---
 include/fmt/chrono.h |  3 ++-
 test/chrono-test.cc  | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/include/fmt/chrono.h b/include/fmt/chrono.h
index 1a2a12cf..43daeeb4 100644
--- a/include/fmt/chrono.h
+++ b/include/fmt/chrono.h
@@ -2142,7 +2142,8 @@ struct formatter<std::chrono::time_point<std::chrono::system_clock, Duration>,
           epoch - std::chrono::duration_cast<std::chrono::seconds>(epoch));
 
       if (subsecs.count() < 0) {
-        auto second = std::chrono::seconds(1);
+        auto second = std::chrono::duration_cast<Duration>(
+            std::chrono::seconds(1));
         if (epoch.count() < ((Duration::min)() + second).count())
           FMT_THROW(format_error("duration is too small"));
         subsecs += second;
diff --git a/test/chrono-test.cc b/test/chrono-test.cc
index 8e2772fa..33c0c2c6 100644
--- a/test/chrono-test.cc
+++ b/test/chrono-test.cc
@@ -850,6 +850,30 @@ TEST(chrono_test, utc_clock) {
 }
 #endif
 
+TEST(chrono_test, timestamps_ratios) {
+  std::chrono::time_point<std::chrono::system_clock, std::chrono::milliseconds>
+      t1(std::chrono::milliseconds(67890));
+
+  EXPECT_EQ(fmt::format("{:%M:%S}", t1), "01:07.890");
+
+  std::chrono::time_point<std::chrono::system_clock, std::chrono::minutes>
+      t2(std::chrono::minutes(7));
+
+  EXPECT_EQ(fmt::format("{:%M:%S}", t2), "07:00");
+
+  std::chrono::time_point<std::chrono::system_clock, 
+                          std::chrono::duration<int, std::ratio<9>>>
+      t3(std::chrono::duration<int, std::ratio<9>>(7));
+
+  EXPECT_EQ(fmt::format("{:%M:%S}", t3), "01:03");
+
+  std::chrono::time_point<std::chrono::system_clock, 
+                          std::chrono::duration<int, std::ratio<63>>>
+      t4(std::chrono::duration<int, std::ratio<63>>(1));
+
+  EXPECT_EQ(fmt::format("{:%M:%S}", t4), "01:03");
+}
+
 TEST(chrono_test, timestamps_sub_seconds) {
   std::chrono::time_point<std::chrono::system_clock,
                           std::chrono::duration<long long, std::ratio<1, 3>>>