fixed bugs in Split

Author: dragon7307

src/Enumerators/System/SpanSplitEnumerator.cs

@@ -1,7 +1,5 @@
 using System;
 using System.Buffers;
-using System.Diagnostics;
-using System.Runtime.CompilerServices;
 
 #if !NET9_0_OR_GREATER
 
@@ -62,7 +60,7 @@ internal SpanSplitEnumerator(ReadOnlySpan<T> source, SearchValues<T> searchValue
                 Delimiter = default!;
                 SearchValues = searchValues;
                 DelimiterSpan = default;
-                mode = SpanSplitEnumeratorMode.Delimiter;
+                mode = SpanSplitEnumeratorMode.SearchValues;
                 currentStartIndex = 0;
                 currentEndIndex = 0;
                 nextStartIndex = 0;
@@ -118,19 +116,19 @@ public bool MoveNext()
                 }
 
                 currentStartIndex = nextStartIndex;
-                
+
                 if(index < 0)
                 {
                     currentEndIndex = Span.Length;
                     nextStartIndex = Span.Length;
-                    
+
                     mode = (SpanSplitEnumeratorMode)(-1);
                     return true;
                 }
 
                 currentEndIndex = currentStartIndex + index;
                 nextStartIndex = currentEndIndex + length;
-                
+
                 return true;
             }
         }

src/ExceptionHelpers.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
-using System.Globalization;
 using System.Numerics;
 using System.Runtime.CompilerServices;
 using SpanExtensions;

src/Extensions/ReadOnlySpan/Span/Split.cs

@@ -1,16 +1,24 @@
 using System;
 using System.Buffers;
-using System.Diagnostics;
 using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 
 #if !NET9_0_OR_GREATER
 
 namespace SpanExtensions
 {
+
 #pragma warning disable CS1591 // Missing XML comment for publicly visible type or member
     public static partial class MemoryExtensions
 #pragma warning restore CS1591 // Missing XML comment for publicly visible type or member
     {
+        static readonly char[] WhiteSpaceDelimiters = new char[] { ' ', '\t', '\n', '\v', '\f', '\r', '\u0085', '\u00A0', '\u1680',
+                        '\u2000', '\u2001', '\u2002', '\u2003', '\u2004', '\u2005', '\u2006', '\u2007', '\u2008', '\u2009',
+                        '\u200A', '\u2028', '\u2029', '\u202F', '\u205F', '\u3000' };
+#if NET8_0
+        static readonly SearchValues<char> WhiteSpaceSearchValues = SearchValues.Create(WhiteSpaceDelimiters);
+#endif
+
         /// <summary>
         /// Returns a type that allows for enumeration of each element within a split span
         /// using the provided separator character.
@@ -47,6 +55,25 @@ public static SpanSplitEnumerator<T> Split<T>(this ReadOnlySpan<T> source, ReadO
         /// <returns>Returns a <see cref="SpanSplitEnumerator{T}"/>.</returns>
         public static SpanSplitEnumerator<T> SplitAny<T>(this ReadOnlySpan<T> source, ReadOnlySpan<T> separators) where T : IEquatable<T>
         {
+            if(separators.Length == 0 && typeof(T) == typeof(char))
+            {
+#if NET8_0
+                return new SpanSplitEnumerator<T>(source, Unsafe.As<SearchValues<T>>(WhiteSpaceSearchValues));
+#elif NET5_0_OR_GREATER
+                ref char data = ref MemoryMarshal.GetArrayDataReference(WhiteSpaceDelimiters);
+                ref T convertedData = ref Unsafe.As<char, T>(ref data);
+                separators = MemoryMarshal.CreateReadOnlySpan(ref convertedData, WhiteSpaceDelimiters.Length);
+#else
+                unsafe
+                {
+                    fixed(char* ptr = &WhiteSpaceDelimiters[0])
+                    {
+                        separators = new ReadOnlySpan<T>(ptr, WhiteSpaceDelimiters.Length);
+                    }
+                }
+#endif
+            }
+
             return new SpanSplitEnumerator<T>(source, separators, SpanSplitEnumeratorMode.Any);
         }
 

src/Extensions/Span/Linq/First.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Reflection;
 
 namespace SpanExtensions
 {

src/Extensions/Span/Span/Split.cs

@@ -1,7 +1,5 @@
 using System;
 using System.Buffers;
-using System.Diagnostics;
-using System.Runtime.CompilerServices;
 
 #if !NET9_0_OR_GREATER
 
@@ -21,7 +19,7 @@ public static partial class MemoryExtensions
         /// <returns>Returns a <see cref="SpanSplitEnumerator{T}"/>.</returns>
         public static SpanSplitEnumerator<T> Split<T>(this Span<T> source, T separator) where T : IEquatable<T>
         {
-            return new SpanSplitEnumerator<T>(source, separator);
+            return Split((ReadOnlySpan<T>)source, separator);
         }
 
         /// <summary>
@@ -34,7 +32,7 @@ public static SpanSplitEnumerator<T> Split<T>(this Span<T> source, T separator)
         /// <returns>Returns a <see cref="SpanSplitEnumerator{T}"/>.</returns>
         public static SpanSplitEnumerator<T> Split<T>(this Span<T> source, ReadOnlySpan<T> separator) where T : IEquatable<T>
         {
-            return new SpanSplitEnumerator<T>(source, separator, SpanSplitEnumeratorMode.Sequence);
+            return Split((ReadOnlySpan<T>)source, separator);
         }
 
         /// <summary>
@@ -47,7 +45,7 @@ public static SpanSplitEnumerator<T> Split<T>(this Span<T> source, ReadOnlySpan<
         /// <returns>Returns a <see cref="SpanSplitEnumerator{T}"/>.</returns>
         public static SpanSplitEnumerator<T> SplitAny<T>(this Span<T> source, ReadOnlySpan<T> separators) where T : IEquatable<T>
         {
-            return new SpanSplitEnumerator<T>(source, separators, SpanSplitEnumeratorMode.Any);
+            return SplitAny((ReadOnlySpan<T>)source, separators);
         }
 
 #if NET8_0
@@ -65,7 +63,7 @@ public static SpanSplitEnumerator<T> SplitAny<T>(this Span<T> source, ReadOnlySp
         /// </remarks>
         public static SpanSplitEnumerator<T> SplitAny<T>(this Span<T> source, SearchValues<T> separators) where T : IEquatable<T>
         {
-            return new SpanSplitEnumerator<T>(source, separators);
+            return SplitAny((ReadOnlySpan<T>)source, separators);
         }
 #endif
 

src/SpanExtensions.csproj

@@ -26,6 +26,7 @@
         <PackageId>SpanExtensions.Net</PackageId>
         <PackageReadmeFile>README.md</PackageReadmeFile>
         <PackageIcon>icon.png</PackageIcon>
+        <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     </PropertyGroup>
 
     <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">

tests/unit-tests/Tests/ReadOnlySpan/Split/SplitAny/Tests.cs

@@ -148,6 +148,31 @@ public void UndefinedCountExceedingBehaviourOptionThrowsArgumentException()
             {
                 Assert.Throws<ArgumentException>(() => ReadOnlySpanExtensions.SplitAny("aabb".AsSpan(), ['b', 'c'], 1, InvalidCountExceedingBehaviour));
             }
+
+            [Fact]
+            public void EmptyDelimitersUsesWhiteSpaceCharacters()
+            {
+                ReadOnlySpan<char> source = "Hello World!\nThis is a test.\rLet's see how it works.";
+                ReadOnlySpan<char> delimiters = "";
+                var expected = new[]
+                {
+                    "Hello".ToCharArray(),
+                    "World!".ToCharArray(),
+                    "This".ToCharArray(),
+                    "is".ToCharArray(),
+                    "a".ToCharArray(),
+                    "test.".ToCharArray(),
+                    "Let's".ToCharArray(),
+                    "see".ToCharArray(),
+                    "how".ToCharArray(),
+                    "it".ToCharArray(),
+                    "works.".ToCharArray()
+                };
+
+                var actual = source.SplitAny(delimiters).ToSystemEnumerable(source);
+
+                Assert.Equal(expected, actual);
+            }
         }
     }
 }

tests/unit-tests/Tests/ReadOnlySpan/Split/SplitAny_StringSplitOptions/Data.cs

@@ -1,6 +1,4 @@
-using static SpanExtensions.Tests.UnitTests.TestHelper;
-
-namespace SpanExtensions.Tests.UnitTests
+namespace SpanExtensions.Tests.UnitTests
 {
     public static partial class ReadOnlySpanSplitTests
     {

tests/unit-tests/ToSystemEnumerableExtensions.cs

@@ -211,5 +211,22 @@ public static IEnumerable<IEnumerable<char>> ToSystemEnumerable(this SpanSplitSe
 
             return list;
         }
+
+        public static IEnumerable<IEnumerable<T>> ToSystemEnumerable<T>(this MemoryExtensions.SpanSplitEnumerator<T> spanEnumerator, ReadOnlySpan<T> span, int maxCount = 100) where T : IEquatable<T>
+        {
+            List<T[]> list = [];
+
+            foreach(Range range in spanEnumerator)
+            {
+                list.Add(span[range].ToArray());
+
+                if(list.Count >= maxCount)
+                {
+                    throw new IndexOutOfRangeException($"Enumeration exceeded {maxCount}.");
+                }
+            }
+
+            return list;
+        }
     }
 }