1 files changed, 28 insertions, 14 deletions

diff --git a/src/mscorlib/corefx/System/Globalization/Calendar.cs b/src/mscorlib/corefx/System/Globalization/Calendar.cs
index 343682d156..78e9f00d08 100644
--- a/src/mscorlib/corefx/System/Globalization/Calendar.cs
+++ b/src/mscorlib/corefx/System/Globalization/Calendar.cs
@@ -2,9 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Runtime.CompilerServices;
-using System.Globalization;
+using System.Diagnostics;
 using System.Diagnostics.Contracts;
 using System.Runtime.Serialization;
 
@@ -99,8 +97,14 @@ namespace System.Globalization
             }
         }
 
-
-
+        [System.Runtime.InteropServices.ComVisible(false)]
+        public virtual CalendarAlgorithmType AlgorithmType
+        {
+            get
+            {
+                return CalendarAlgorithmType.Unknown;
+            }
+        }
 
         protected Calendar()
         {
@@ -164,9 +168,9 @@ namespace System.Globalization
         //
         ////////////////////////////////////////////////////////////////////////
         [System.Runtime.InteropServices.ComVisible(false)]
-        internal static Calendar ReadOnly(Calendar calendar)
+        public static Calendar ReadOnly(Calendar calendar)
         {
-            if (calendar == null) { throw new ArgumentNullException("calendar"); }
+            if (calendar == null) { throw new ArgumentNullException(nameof(calendar)); }
             Contract.EndContractBlock();
             if (calendar.IsReadOnly) { return (calendar); }
 
@@ -206,7 +210,7 @@ namespace System.Globalization
                 // The following code assumes that the current era value can not be -1.
                 if (_currentEraValue == -1)
                 {
-                    Contract.Assert(BaseCalendarID != CalendarId.UNINITIALIZED_VALUE, "[Calendar.CurrentEraValue] Expected a real calendar ID");
+                    Debug.Assert(BaseCalendarID != CalendarId.UNINITIALIZED_VALUE, "[Calendar.CurrentEraValue] Expected a real calendar ID");
                     _currentEraValue = CalendarData.GetCalendarData(BaseCalendarID).iCurrentEra;
                 }
                 return (_currentEraValue);
@@ -242,7 +246,7 @@ namespace System.Globalization
             double tempMillis = (value * scale + (value >= 0 ? 0.5 : -0.5));
             if (!((tempMillis > -(double)MaxMillis) && (tempMillis < (double)MaxMillis)))
             {
-                throw new ArgumentOutOfRangeException("value", SR.ArgumentOutOfRange_AddValue);
+                throw new ArgumentOutOfRangeException(nameof(value), SR.ArgumentOutOfRange_AddValue);
             }
 
             long millis = (long)tempMillis;
@@ -521,7 +525,7 @@ namespace System.Globalization
             // this value can be less than 0.  It's fine since we are making it positive again in calculating offset.
             int dayForJan1 = (int)GetDayOfWeek(time) - (dayOfYear % 7);
             int offset = (dayForJan1 - firstDayOfWeek + 14) % 7;
-            Contract.Assert(offset >= 0, "Calendar.GetFirstDayWeekOfYear(): offset >= 0");
+            Debug.Assert(offset >= 0, "Calendar.GetFirstDayWeekOfYear(): offset >= 0");
             return ((dayOfYear + offset) / 7 + 1);
         }
 
@@ -646,7 +650,7 @@ namespace System.Globalization
             if ((int)firstDayOfWeek < 0 || (int)firstDayOfWeek > 6)
             {
                 throw new ArgumentOutOfRangeException(
-                    "firstDayOfWeek", SR.Format(SR.ArgumentOutOfRange_Range,
+                    nameof(firstDayOfWeek), SR.Format(SR.ArgumentOutOfRange_Range,
                     DayOfWeek.Sunday, DayOfWeek.Saturday));
             }
             Contract.EndContractBlock();
@@ -660,7 +664,7 @@ namespace System.Globalization
                     return (GetWeekOfYearFullDays(time, (int)firstDayOfWeek, 4));
             }
             throw new ArgumentOutOfRangeException(
-                "rule", SR.Format(SR.ArgumentOutOfRange_Range,
+                nameof(rule), SR.Format(SR.ArgumentOutOfRange_Range,
                 CalendarWeekRule.FirstDay, CalendarWeekRule.FirstFourDayWeek));
         }
 
@@ -700,6 +704,16 @@ namespace System.Globalization
 
         public abstract bool IsLeapMonth(int year, int month, int era);
 
+        // Returns  the leap month in a calendar year of the current era. This method returns 0
+        // if this calendar does not have leap month, or this year is not a leap year.
+        //
+
+        [System.Runtime.InteropServices.ComVisible(false)]
+        public virtual int GetLeapMonth(int year)
+        {
+            return (GetLeapMonth(year, CurrentEra));
+        }
+
         // Returns  the leap month in a calendar year of the specified era. This method returns 0
         // if this calendar does not have leap month, or this year is not a leap year.
         //
@@ -808,7 +822,7 @@ namespace System.Globalization
         {
             if (year < 0)
             {
-                throw new ArgumentOutOfRangeException("year",
+                throw new ArgumentOutOfRangeException(nameof(year),
                     SR.ArgumentOutOfRange_NeedNonNegNum);
             }
             Contract.EndContractBlock();
@@ -830,7 +844,7 @@ namespace System.Globalization
                 if (millisecond < 0 || millisecond >= MillisPerSecond)
                 {
                     throw new ArgumentOutOfRangeException(
-                                "millisecond",
+                                nameof(millisecond),
                                 String.Format(
                                     CultureInfo.InvariantCulture,
                                     SR.Format(SR.ArgumentOutOfRange_Range, 0, MillisPerSecond - 1)));