CachedUntil - Clamp CachedSeconds expiry to DateTime.MaxValue

src/NLog/LayoutRenderers/Wrappers/CachedLayoutRendererWrapper.cs

@@ -208,7 +208,12 @@ namespace NLog.LayoutRenderers.Wrappers
 
         private DateTime? ResolveCachedValueExpires(DateTime timeStamp)
         {
-            DateTime? expires = _cachedValueTimeout.HasValue ? timeStamp + _cachedValueTimeout.Value : null;
+            DateTime? expires = null;
+            if (_cachedValueTimeout.HasValue)
+            {
+                var timeoutTicks = Math.Min(_cachedValueTimeout.Value.Ticks, DateTime.MaxValue.Ticks - timeStamp.Ticks);
+                expires = timeStamp.AddTicks(timeoutTicks);
+            }
             if (_cachedUntil != CachedUntilLifetime.None)
             {
                 var periodTicks = _cachedUntil == CachedUntilLifetime.DayChange ? TimeSpan.TicksPerDay : TimeSpan.TicksPerHour;

tests/NLog.UnitTests/LayoutRenderers/Wrappers/CachedTests.cs

@@ -154,11 +154,13 @@ namespace NLog.UnitTests.LayoutRenderers.Wrappers
         }
 
         [Theory]
-        [InlineData("HourChange")]
+        [InlineData("cachedUntil=HourChange")]
-        [InlineData("DayChange")]
+        [InlineData("cachedUntil=DayChange")]
-        public void CachedUntilLastPeriodTest(string cachedUntil)
+        [InlineData("cachedSeconds=3600")]
+        [InlineData("cachedUntil=DayChange:cachedSeconds=3600")]
+        public void CachedLastPeriodTest(string cachedOptions)
         {
-            SimpleLayout l = "${guid:cachedUntil=" + cachedUntil + "}";
+            SimpleLayout l = "${guid:" + cachedOptions + "}";
             var s1 = l.Render(new LogEventInfo() { TimeStamp = DateTime.MaxValue.AddMinutes(-30) });
             var s2 = l.Render(new LogEventInfo() { TimeStamp = DateTime.MaxValue });
             Assert.NotEmpty(s1);