Microoptimizations on DateTimeParser

.gitignore

@@ -12,6 +12,7 @@ BenchmarkDotNet.Artifacts/
 _ReSharper.*
 *.ReSharper.user
 *.resharper.user
+*/.idea/*
 .vs/
 .vscode/
 *.lock.json

Src/Newtonsoft.Json.Tests/Benchmarks/DeserializeBenchmarks.cs

@@ -27,27 +27,43 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
 using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using System.Xml;
 using BenchmarkDotNet.Attributes;
 using Newtonsoft.Json.Linq;
-using Newtonsoft.Json;
 using Newtonsoft.Json.Tests.TestObjects;
+using Newtonsoft.Json.Utilities;
 
 namespace Newtonsoft.Json.Tests.Benchmarks
 {
     public class DeserializeBenchmarks
     {
         private static readonly string LargeJsonText;
         private static readonly string FloatArrayJson;
+        private static readonly string DateArrayJson;
+        private static readonly StringReference[] DateTimeStringReferences;
+        private static readonly DateTimeOffset[] ParsedDateTimesArray;
+        private static readonly JsonSerializer Serializer = new();
 
         static DeserializeBenchmarks()
         {
             LargeJsonText = System.IO.File.ReadAllText(TestFixtureBase.ResolvePath("large.json"));
 
-            FloatArrayJson = new JArray(Enumerable.Range(0, 5000).Select(i => i * 1.1m)).ToString(Formatting.None);
+            const int count = 5000;
+            FloatArrayJson = new JArray(Enumerable.Range(0, count).Select(i => i * 1.1m)).ToString(Formatting.None);
+            var dates = new DateTime[count];
+            DateTimeStringReferences = new StringReference[count];
+            ParsedDateTimesArray = new DateTimeOffset[count];
+            DateTime time = new(1969, 7, 20, 2, 56, 15, DateTimeKind.Utc);
+            for (int i = 0; i < count; i++)
+            {
+                DateTime dateTime = time.AddDays(i);
+                dates[i] = dateTime;
+                string dateTimeString = dateTime.ToString("O", CultureInfo.InvariantCulture);
+                DateTimeStringReferences[i] = new StringReference(dateTimeString.ToCharArray(), 0, dateTimeString.Length);
+            }
+            DateArrayJson = new JArray(dates).ToString(Formatting.None);
         }
 
         [Benchmark]
@@ -59,11 +75,10 @@ public IList<RootObject> DeserializeLargeJsonText()
         [Benchmark]
         public IList<RootObject> DeserializeLargeJsonFile()
         {
-            using (var jsonFile = System.IO.File.OpenText(TestFixtureBase.ResolvePath("large.json")))
+            using StringReader jsonFile = new(LargeJsonText);
             using (JsonTextReader jsonTextReader = new JsonTextReader(jsonFile))
             {
-                JsonSerializer serializer = new JsonSerializer();
-                return serializer.Deserialize<IList<RootObject>>(jsonTextReader);
+                return Serializer.Deserialize<IList<RootObject>>(jsonTextReader);
             }
         }
 
@@ -78,6 +93,24 @@ public IList<decimal> DeserializeDecimalList()
         {
             return JsonConvert.DeserializeObject<IList<decimal>>(FloatArrayJson);
         }
+
+        [Benchmark]
+        public IList<DateTime> DeserializeDateTimeList()
+        {
+            return JsonConvert.DeserializeObject<IList<DateTime>>(DateArrayJson);
+        }
+
+        [Benchmark]
+        public bool TryParseDateTimeOffsetIso()
+        {
+            bool success = true;
+            for (var index = 0; index < DateTimeStringReferences.Length; index++)
+            {
+                success &= DateTimeUtils.TryParseDateTimeOffsetIso(DateTimeStringReferences[index], out DateTimeOffset result);
+                ParsedDateTimesArray[index] = result;
+            }
+            return success;
+        }
     }
 }
 

Src/Newtonsoft.Json.Tests/Benchmarks/SerializeBenchmarks.cs

@@ -25,23 +25,19 @@
 
 #if HAVE_BENCHMARKS
 
-using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using System.Xml;
 using BenchmarkDotNet.Attributes;
-using Newtonsoft.Json.Linq;
-using Newtonsoft.Json;
 using Newtonsoft.Json.Tests.TestObjects;
 
 namespace Newtonsoft.Json.Tests.Benchmarks
 {
     public class SerializeBenchmarks
     {
         private static readonly IList<RootObject> LargeCollection;
+        private static readonly MemoryStream ReusedMemoryStream = new();
+        private static readonly StreamWriter JsonFile = new(ReusedMemoryStream);
+        private static readonly JsonSerializer Serializer = new() { Formatting = Formatting.Indented };
 
         static SerializeBenchmarks()
         {
@@ -53,12 +49,8 @@ static SerializeBenchmarks()
         [Benchmark]
         public void SerializeLargeJsonFile()
         {
-            using (StreamWriter file = System.IO.File.CreateText(TestFixtureBase.ResolvePath("largewrite.json")))
-            {
-                JsonSerializer serializer = new JsonSerializer();
-                serializer.Formatting = Formatting.Indented;
-                serializer.Serialize(file, LargeCollection);
-            }
+            ReusedMemoryStream.Seek(0, SeekOrigin.Begin);
+            Serializer.Serialize(JsonFile, LargeCollection);
         }
     }
 }

Src/Newtonsoft.Json.Tests/Issues/Issue2768.cs

@@ -71,15 +71,15 @@ public void Test_Deserialize()
         {
             decimal d = JsonConvert.DeserializeObject<decimal>("0.0");
 
-            Assert.AreEqual("0.0", d.ToString());
+            Assert.AreEqual("0.0", d.ToString(CultureInfo.InvariantCulture));
         }
 
         [Test]
         public void Test_Deserialize_Negative()
         {
             decimal d = JsonConvert.DeserializeObject<decimal>("-0.0");
 
-            Assert.AreEqual("0.0", d.ToString());
+            Assert.AreEqual("0.0", d.ToString(CultureInfo.InvariantCulture));
         }
 
         [Test]
@@ -95,7 +95,7 @@ public void Test_Deserialize_MultipleTrailingZeroes()
         {
             decimal d = JsonConvert.DeserializeObject<decimal>("0.00");
 
-            Assert.AreEqual("0.00", d.ToString());
+            Assert.AreEqual("0.00", d.ToString(CultureInfo.InvariantCulture));
         }
 
         [Test]
@@ -127,7 +127,7 @@ public void ParseJsonDecimal()
                 }
             }
 
-            Assert.AreEqual("0.0", parsedValue.ToString());
+            Assert.AreEqual("0.0", parsedValue?.ToString(CultureInfo.InvariantCulture));
         }
 
         [Test]

Src/Newtonsoft.Json.Tests/JsonConvertTest.cs

@@ -778,7 +778,7 @@ public void WriteDateTime()
             Assert.AreEqual(@"\/Date(253402300799999)\/", result.MsDateUtc);
 
             DateTime year2000local = new DateTime(2000, 1, 1, 1, 1, 1, DateTimeKind.Local);
-            string localToUtcDate = year2000local.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK");
+            string localToUtcDate = year2000local.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK", CultureInfo.InvariantCulture);
 
             result = TestDateTime("DateTime Local", year2000local);
             Assert.AreEqual("2000-01-01T01:01:01" + GetOffset(year2000local, DateFormatHandling.IsoDateFormat), result.IsoDateRoundtrip);
@@ -791,7 +791,7 @@ public void WriteDateTime()
             Assert.AreEqual(@"\/Date(" + DateTimeUtils.ConvertDateTimeToJavaScriptTicks(year2000local) + @")\/", result.MsDateUtc);
 
             DateTime millisecondsLocal = new DateTime(2000, 1, 1, 1, 1, 1, 999, DateTimeKind.Local);
-            localToUtcDate = millisecondsLocal.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK");
+            localToUtcDate = millisecondsLocal.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK", CultureInfo.InvariantCulture);
 
             result = TestDateTime("DateTime Local with milliseconds", millisecondsLocal);
             Assert.AreEqual("2000-01-01T01:01:01.999" + GetOffset(millisecondsLocal, DateFormatHandling.IsoDateFormat), result.IsoDateRoundtrip);
@@ -804,7 +804,7 @@ public void WriteDateTime()
             Assert.AreEqual(@"\/Date(" + DateTimeUtils.ConvertDateTimeToJavaScriptTicks(millisecondsLocal) + @")\/", result.MsDateUtc);
 
             DateTime ticksLocal = new DateTime(636556897826822481, DateTimeKind.Local);
-            localToUtcDate = ticksLocal.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK");
+            localToUtcDate = ticksLocal.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.FFFFFFFK", CultureInfo.InvariantCulture);
 
             result = TestDateTime("DateTime Local with ticks", ticksLocal);
             Assert.AreEqual("2018-03-03T16:03:02.6822481" + GetOffset(ticksLocal, DateFormatHandling.IsoDateFormat), result.IsoDateRoundtrip);
@@ -829,7 +829,7 @@ public void WriteDateTime()
             Assert.AreEqual(@"\/Date(" + DateTimeUtils.ConvertDateTimeToJavaScriptTicks(year2000Unspecified.ToLocalTime()) + @")\/", result.MsDateUtc);
 
             DateTime year2000Utc = new DateTime(2000, 1, 1, 1, 1, 1, DateTimeKind.Utc);
-            string utcTolocalDate = year2000Utc.ToLocalTime().ToString("yyyy-MM-ddTHH:mm:ss");
+            string utcTolocalDate = year2000Utc.ToLocalTime().ToString("yyyy-MM-ddTHH:mm:ss", CultureInfo.InvariantCulture);
 
             result = TestDateTime("DateTime Utc", year2000Utc);
             Assert.AreEqual("2000-01-01T01:01:01Z", result.IsoDateRoundtrip);
@@ -842,7 +842,7 @@ public void WriteDateTime()
             Assert.AreEqual(@"\/Date(946688461000)\/", result.MsDateUtc);
 
             DateTime unixEpoc = new DateTime(621355968000000000, DateTimeKind.Utc);
-            utcTolocalDate = unixEpoc.ToLocalTime().ToString("yyyy-MM-ddTHH:mm:ss");
+            utcTolocalDate = unixEpoc.ToLocalTime().ToString("yyyy-MM-ddTHH:mm:ss", CultureInfo.InvariantCulture);
 
             result = TestDateTime("DateTime Unix Epoc", unixEpoc);
             Assert.AreEqual("1970-01-01T00:00:00Z", result.IsoDateRoundtrip);

Src/Newtonsoft.Json/Utilities/DateTimeParser.cs

@@ -24,17 +24,19 @@
 #endregion
 
 using System;
+using System.Runtime.InteropServices;
 
 namespace Newtonsoft.Json.Utilities
 {
-    internal enum ParserTimeZone
+    internal enum ParserTimeZone : byte
     {
         Unspecified = 0,
         Utc = 1,
         LocalWestOfUtc = 2,
         LocalEastOfUtc = 3
     }
 
+    [StructLayout(LayoutKind.Auto)]
     internal struct DateTimeParser
     {
         static DateTimeParser()
@@ -56,15 +58,15 @@ static DateTimeParser()
             Lz_zz = "-zz".Length;
         }
 
-        public int Year;
-        public int Month;
-        public int Day;
-        public int Hour;
-        public int Minute;
-        public int Second;
+        public ushort Year;
+        public byte Month;
+        public byte Day;
+        public byte Hour;
+        public byte Minute;
+        public byte Second;
         public int Fraction;
-        public int ZoneHour;
-        public int ZoneMinute;
+        public byte ZoneHour;
+        public byte ZoneMinute;
         public ParserTimeZone Zone;
 
         private char[] _text;
@@ -130,7 +132,7 @@ private bool ParseTime(ref int start)
                   && ParseChar(start + LzHH_mm, ':')
                   && Parse2Digit(start + LzHH_mm_, out Second)
                   && Second < 60
-                  && (Hour != 24 || (Minute == 0 && Second == 0)))) // hour can be 24 if minute/second is zero)
+                  && ((Minute == 0 && Second == 0) || Hour != 24))) // hour can be 24 if minute/second is zero)
             {
                 return false;
             }
@@ -231,7 +233,7 @@ private bool ParseZone(int start)
             return (start == _end);
         }
 
-        private bool Parse4Digit(int start, out int num)
+        private bool Parse4Digit(int start, out ushort num)
         {
             if (start + 3 < _end)
             {
@@ -244,24 +246,25 @@ private bool Parse4Digit(int start, out int num)
                     && 0 <= digit3 && digit3 < 10
                     && 0 <= digit4 && digit4 < 10)
                 {
-                    num = (((((digit1 * 10) + digit2) * 10) + digit3) * 10) + digit4;
+                    num = (ushort)((((((digit1 * 10) + digit2) * 10) + digit3) * 10) + digit4);
                     return true;
                 }
             }
             num = 0;
             return false;
         }
 
-        private bool Parse2Digit(int start, out int num)
+        private bool Parse2Digit(int start, out byte num)
         {
-            if (start + 1 < _end)
+            int end = start + 1;
+            if (end < _end)
             {
                 int digit1 = _text[start] - '0';
-                int digit2 = _text[start + 1] - '0';
+                int digit2 = _text[end] - '0';
                 if (0 <= digit1 && digit1 < 10
                     && 0 <= digit2 && digit2 < 10)
                 {
-                    num = (digit1 * 10) + digit2;
+                    num = (byte)((digit1 * 10) + digit2);
                     return true;
                 }
             }