[util] speedup GmTimeR outside LUT interval

commit_hash:d57be220df393c193619ef5ed129ec4436540629

1 files changed, 14 insertions, 4 deletions

diff --git a/util/datetime/base_ut.cpp b/util/datetime/base_ut.cpp
index cc2e776e48..3ac1a90a90 100644
--- a/util/datetime/base_ut.cpp
+++ b/util/datetime/base_ut.cpp
@@ -310,10 +310,8 @@ Y_UNIT_TEST_SUITE(TDateTimeTest) {
                && true;
     }
 
-    Y_UNIT_TEST(TestGmTimeR) {
-        time_t starttime = static_cast<time_t>(Max<i64>(-12244089600LL, Min<time_t>())); // 1-Jan-1582
-        time_t finishtime = static_cast<time_t>(Min<i64>(0xFFFFFFFF * 20, Max<time_t>()));
-        time_t step = (finishtime - starttime) / 25;
+    void TestGmTimeR(time_t starttime, time_t finishtime, int steps) {
+        time_t step = (finishtime - starttime) / steps;
         struct tm tms0, tms1;
         struct tm* ptm0 = nullptr;
         struct tm* ptm1 = nullptr;
@@ -336,6 +334,18 @@ Y_UNIT_TEST_SUITE(TDateTimeTest) {
             UNIT_ASSERT(CompareTMFull(ptm0, ptm1));
         }
     }
+
+    Y_UNIT_TEST(TestGmTimeRLongRange) {
+        time_t starttime = static_cast<time_t>(-86397839500LL); // 29-Jan-2668 B.C.
+        time_t finishtime = static_cast<time_t>(0xFFFFFFFF * 20);
+        TestGmTimeR(starttime, finishtime, 101);
+    }
+
+    Y_UNIT_TEST(TestGmTimeRNowdays) {
+        time_t starttime = static_cast<time_t>(0);             // 1970
+        time_t finishtime = static_cast<time_t>(6307200000LL); // 2170
+        TestGmTimeR(starttime, finishtime, 303);
+    }
 } // Y_UNIT_TEST_SUITE(TDateTimeTest)
 
 Y_UNIT_TEST_SUITE(DateTimeTest) {