Remove ImmutableArray integration

Badeend.ValueCollections.Tests/Badeend.ValueCollections.Tests.csproj

@@ -15,7 +15,6 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.5.0" />
-    <PackageReference Include="System.Collections.Immutable" Version="5.0.0" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

Badeend.ValueCollections.Tests/Reference/ValueList.Tests.IndexOf.cs

@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.Linq;
 using Xunit;
 

Badeend.ValueCollections.Tests/ValueListTests.cs

@@ -118,22 +118,6 @@ public void HashCode()
         Assert.True(hashCodes.Count() == hashCodes.Distinct().Count());
     }
 
-    /// <summary>
-    /// FYI, this is not something we publicly promise, but we test for it anyways.
-    /// </summary>
-    [Fact]
-    public void ImmutableArrayRoundtrip()
-    {
-        int[] unsafeItems = [1, 2, 3, 4];
-
-        var list = ValueCollectionsMarshal.AsValueList(unsafeItems)
-            .ToImmutableArray()
-            .AsValueList();
-
-        unsafeItems[1] = 42;
-        Assert.True(list[1] == 42);
-    }
-
     [Fact]
     public void MarshalAsValueList()
     {

Badeend.ValueCollections.Tests/ValueSliceTests.cs

@@ -164,22 +164,6 @@ public void HashCode()
         Assert.True(hashCodes.Count() == hashCodes.Distinct().Count());
     }
 
-    /// <summary>
-    /// FYI, this is not something we publicly promise, but we test for it anyways.
-    /// </summary>
-    [Fact]
-    public void ImmutableArrayRoundtrip()
-    {
-        int[] unsafeItems = [1, 2, 3, 4];
-
-        var slice = ValueCollectionsMarshal.AsValueSlice(unsafeItems)
-            .ToImmutableArray()
-            .AsValueSlice();
-
-        unsafeItems[1] = 42;
-        Assert.True(slice[1] == 42);
-    }
-
     [Fact]
     public void MarshalAsValueSlice()
     {

Badeend.ValueCollections/Badeend.ValueCollections.csproj

@@ -6,7 +6,6 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Bcl.HashCode" Version="1.0.0" Condition="'$(TargetFramework)' == 'netstandard2.0'" />
-    <PackageReference Include="System.Collections.Immutable" Version="1.2.0" />
     <PackageReference Include="System.Memory" Version="4.5.0" Condition="'$(TargetFramework)' == 'netstandard2.0'" />
     <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.5.0" Condition="'$(TargetFramework)' == 'netstandard2.0' or '$(TargetFramework)' == 'netstandard2.1' or '$(TargetFramework)' == 'netcoreapp2.1'" />
   </ItemGroup>

Badeend.ValueCollections/UnsafeHelpers.cs

@@ -1,4 +1,3 @@
-using System.Collections.Immutable;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
@@ -33,18 +32,6 @@ private static void PlatformAssert(bool condition)
 		}
 	}
 
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	internal static T[] AsArray<T>(ImmutableArray<T> items)
-	{
-		return Unsafe.As<ImmutableArray<T>, T[]>(ref items);
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	internal static ImmutableArray<T> AsImmutableArray<T>(T[] items)
-	{
-		return Unsafe.As<T[], ImmutableArray<T>>(ref items);
-	}
-
 	[MethodImpl(MethodImplOptions.AggressiveInlining)]
 	internal static Span<T> AsSpan<T>(List<T> items)
 	{

Badeend.ValueCollections/ValueCollectionExtensions.cs

@@ -1,4 +1,3 @@
-using System.Collections.Immutable;
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
 
@@ -9,29 +8,6 @@ namespace Badeend.ValueCollections;
 /// </summary>
 public static class ValueCollectionExtensions
 {
-	/// <summary>
-	/// Reinterpret the <see cref="ImmutableArray{T}"/> as a <see cref="ValueSlice{T}"/>.
-	/// This does not allocate any memory.
-	/// </summary>
-	public static ValueSlice<T> AsValueSlice<T>(this ImmutableArray<T> items) => new(UnsafeHelpers.AsArray(items));
-
-	/// <summary>
-	/// Create a new <see cref="ValueList{T}"/> that reuses the backing allocation
-	/// of the <see cref="ImmutableArray{T}"/>.
-	///
-	/// This method allocates a new fixed-size ValueList instance. The items
-	/// are not copied.
-	/// </summary>
-	public static ValueList<T> AsValueList<T>(this ImmutableArray<T> items) => ValueList<T>.FromArrayUnsafe(UnsafeHelpers.AsArray(items));
-
-	/// <summary>
-	/// Copy the <paramref name="items"/> into a new <see cref="ValueList{T}"/>.
-	/// </summary>
-	[Obsolete("Use .AsValueList() instead.")]
-	[Browsable(false)]
-	[EditorBrowsable(EditorBrowsableState.Never)]
-	public static ValueList<T> ToValueList<T>(this ImmutableArray<T> items) => ValueList<T>.FromArrayUnsafe(items.ToArray());
-
 	/// <summary>
 	/// Copy the <paramref name="items"/> into a new <see cref="ValueList{T}"/>.
 	/// </summary>

Badeend.ValueCollections/ValueList.cs

@@ -1,5 +1,4 @@
 using System.Collections;
-using System.Collections.Immutable;
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
 using System.Text;
@@ -225,11 +224,6 @@ internal static ValueList<T> FromArrayUnsafe(T[] items, int count)
 	/// </summary>
 	public bool TryCopyTo(Span<T> destination) => this.AsValueSlice().TryCopyTo(destination);
 
-	/// <summary>
-	/// Copy the list into a new <see cref="ImmutableArray{T}"/>.
-	/// </summary>
-	public ImmutableArray<T> ToImmutableArray() => this.AsValueSlice().ToImmutableArray();
-
 	/// <summary>
 	/// Create a new <see cref="ValueListBuilder{T}"/> with this list as its
 	/// initial content. This builder can then be used to efficiently construct

Badeend.ValueCollections/ValueSlice.cs

@@ -1,5 +1,4 @@
 using System.Collections;
-using System.Collections.Immutable;
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Runtime.CompilerServices;
@@ -217,27 +216,6 @@ public ValueList<T> ToValueList()
 		return ValueList<T>.FromArrayUnsafe(this.ToArray());
 	}
 
-	/// <summary>
-	/// Copy the slice into a new <see cref="ImmutableArray{T}"/>.
-	/// </summary>
-	public ImmutableArray<T> ToImmutableArray()
-	{
-		if (this.items is null)
-		{
-			return ImmutableArray<T>.Empty;
-		}
-		else if (this.length == this.items.Length)
-		{
-			Debug.Assert(this.offset == 0);
-
-			return UnsafeHelpers.AsImmutableArray(this.items);
-		}
-		else
-		{
-			return ImmutableArray.Create(this.items, this.offset, this.length);
-		}
-	}
-
 	/// <summary>
 	/// Copy the contents of the slice into a new array.
 	///