From 97292830a5e68aecccfa133bd9ecca88b116fce6 Mon Sep 17 00:00:00 2001
From: iskcal <cross_icon@outlook.com>
Date: Mon, 24 Aug 2020 01:12:00 +0800
Subject: [PATCH] Compare two DateTime object with the same DateTimeKind

---
 src/Humanizer.Tests.Shared/DateHumanize.cs |  6 +++++-
 src/Humanizer/DateHumanizeExtensions.cs    | 19 ++++++++-----------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/Humanizer.Tests.Shared/DateHumanize.cs b/src/Humanizer.Tests.Shared/DateHumanize.cs
index edfd67c1a..ce6b6c796 100644
--- a/src/Humanizer.Tests.Shared/DateHumanize.cs
+++ b/src/Humanizer.Tests.Shared/DateHumanize.cs
@@ -32,6 +32,10 @@ private static void VerifyWithDate(string expectedString, TimeSpan deltaFromBase
         {
             Assert.Equal(expectedString, baseDateUtc.Add(deltaFromBase).Humanize(utcDate: true, dateToCompareAgainst: baseDateUtc, culture: culture));
             Assert.Equal(expectedString, baseDate.Add(deltaFromBase).Humanize(false, baseDate, culture: culture));
+
+            // Compared with default utcDate
+            Assert.Equal(expectedString, baseDateUtc.Add(deltaFromBase).Humanize(utcDate: null, dateToCompareAgainst: baseDateUtc, culture: culture));
+            Assert.Equal(expectedString, baseDate.Add(deltaFromBase).Humanize(null, baseDate, culture: culture));
         }
 
         public static void Verify(string expectedString, int unit, TimeUnit timeUnit, Tense tense, double? precision = null, CultureInfo culture = null, DateTime? baseDate = null, DateTime? baseDateUtc = null)
@@ -93,4 +97,4 @@ public static void Verify(string expectedString, int unit, TimeUnit timeUnit, Te
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/Humanizer/DateHumanizeExtensions.cs b/src/Humanizer/DateHumanizeExtensions.cs
index 7047b2f69..86c6493ac 100644
--- a/src/Humanizer/DateHumanizeExtensions.cs
+++ b/src/Humanizer/DateHumanizeExtensions.cs
@@ -13,18 +13,15 @@ public static class DateHumanizeExtensions
         /// Turns the current or provided date into a human readable sentence
         /// </summary>
         /// <param name="input">The date to be humanized</param>
-        /// <param name="utcDate">Boolean value indicating whether the date is in UTC or local</param>
+        /// <param name="utcDate">Nullable boolean value indicating whether the date is in UTC or local. If null, current date is used with the same DateTimeKind of input</param>
         /// <param name="dateToCompareAgainst">Date to compare the input against. If null, current date is used as base</param>
         /// <param name="culture">Culture to use. If null, current thread's UI culture is used.</param>
         /// <returns>distance of time in words</returns>
-        public static string Humanize(this DateTime input, bool utcDate = true, DateTime? dateToCompareAgainst = null, CultureInfo culture = null)
+        public static string Humanize(this DateTime input, bool? utcDate = null, DateTime? dateToCompareAgainst = null, CultureInfo culture = null)
         {
-            var comparisonBase = dateToCompareAgainst ?? DateTime.UtcNow;
-
-            if (!utcDate)
-            {
-                comparisonBase = comparisonBase.ToLocalTime();
-            }
+            var comparisonBase = dateToCompareAgainst.HasValue ? dateToCompareAgainst.Value : DateTime.UtcNow;
+            utcDate ??= input.Kind != DateTimeKind.Local;
+            comparisonBase = utcDate.Value ? comparisonBase.ToUniversalTime() : comparisonBase.ToLocalTime();
 
             return Configurator.DateTimeHumanizeStrategy.Humanize(input, comparisonBase, culture);
         }
@@ -33,11 +30,11 @@ public static string Humanize(this DateTime input, bool utcDate = true, DateTime
         /// Turns the current or provided date into a human readable sentence, overload for the nullable DateTime, returning 'never' in case null
         /// </summary>
         /// <param name="input">The date to be humanized</param>
-        /// <param name="utcDate">Boolean value indicating whether the date is in UTC or local</param>
+        /// <param name="utcDate">Nullable boolean value indicating whether the date is in UTC or local. If null, current date is used with the same DateTimeKind of input</param>
         /// <param name="dateToCompareAgainst">Date to compare the input against. If null, current date is used as base</param>
         /// <param name="culture">Culture to use. If null, current thread's UI culture is used.</param>
         /// <returns>distance of time in words</returns>
-        public static string Humanize(this DateTime? input, bool utcDate = true, DateTime? dateToCompareAgainst = null, CultureInfo culture = null)
+        public static string Humanize(this DateTime? input, bool? utcDate = null, DateTime? dateToCompareAgainst = null, CultureInfo culture = null)
         {
             if (input.HasValue)
             {
@@ -82,4 +79,4 @@ public static string Humanize(this DateTimeOffset? input, DateTimeOffset? dateTo
             }
         }
     }
-}
\ No newline at end of file
+}