From 88a0889457dd77ce4e8f8470bb40c25798ca330e Mon Sep 17 00:00:00 2001
From: Matthew O'Connor <matthew.oconnor@xledger.com>
Date: Wed, 16 Oct 2024 11:55:10 -0600
Subject: [PATCH] Support collection builders in .NET 8+.

---
 Xledger.Collections.Test/TestImmArray.cs             |  9 +++++++++
 Xledger.Collections.Test/TestImmSet.cs               |  9 +++++++++
 .../Xledger.Collections.Test.csproj                  |  7 +++++--
 Xledger.Collections/Extensions.cs                    | 12 ++++++++++++
 Xledger.Collections/ImmArray.cs                      |  9 +++++++++
 Xledger.Collections/ImmSet.cs                        |  9 +++++++++
 Xledger.Collections/Xledger.Collections.csproj       |  2 +-
 7 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/Xledger.Collections.Test/TestImmArray.cs b/Xledger.Collections.Test/TestImmArray.cs
index 39332f1..cfcf592 100644
--- a/Xledger.Collections.Test/TestImmArray.cs
+++ b/Xledger.Collections.Test/TestImmArray.cs
@@ -32,6 +32,15 @@ public void TestSingle() {
         Assert.Equal(imm2, imm1);
     }
 
+#if NET8_0_OR_GREATER
+    [Fact]
+    public void TestCollectionBuilder() {
+        var ys = ImmArray.Of("hi", "how", "are", "you?");
+        ImmArray<string> xs = ["hi", "how", "are", "you?"];
+        Assert.Equal(ys, xs);
+    }
+#endif
+
     [Fact]
     public void TestCopy() {
         int[] arr = [1, 2, 3, 4, 5, 6];
diff --git a/Xledger.Collections.Test/TestImmSet.cs b/Xledger.Collections.Test/TestImmSet.cs
index 6bd2f69..cd9462e 100644
--- a/Xledger.Collections.Test/TestImmSet.cs
+++ b/Xledger.Collections.Test/TestImmSet.cs
@@ -32,6 +32,15 @@ public void TestSingle() {
         Assert.Equal(imm2, imm1);
     }
 
+#if NET8_0_OR_GREATER
+    [Fact]
+    public void TestCollectionBuilder() {
+        var ys = ImmSet.Of("hi", "how", "are", "you?");
+        ImmSet<string> xs = ["hi", "how", "are", "you?"];
+        Assert.Equal(ys, xs);
+    }
+#endif
+
     [Fact]
     public void TestCopy() {
         int[] arr = [1, 2, 3, 4, 5, 6];
diff --git a/Xledger.Collections.Test/Xledger.Collections.Test.csproj b/Xledger.Collections.Test/Xledger.Collections.Test.csproj
index 4b3f39d..6390632 100644
--- a/Xledger.Collections.Test/Xledger.Collections.Test.csproj
+++ b/Xledger.Collections.Test/Xledger.Collections.Test.csproj
@@ -3,12 +3,15 @@
   <PropertyGroup>
     <PackageId>Xledger.Collections.Test</PackageId>
 
-    <TargetFrameworks>net48;net6.0</TargetFrameworks>
+    <TargetFrameworks>net48;net6.0;net8.0</TargetFrameworks>
     <LangVersion>12.0</LangVersion>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>disable</Nullable>
 
     <IsPackable>false</IsPackable>
+
+    <!-- To allow use in .NET 8 -->
+    <EnableUnsafeBinaryFormatterSerialization>true</EnableUnsafeBinaryFormatterSerialization>
   </PropertyGroup>
 
   <PropertyGroup>
@@ -19,7 +22,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.2" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
-    <PackageReference Include="System.Text.Json" Version="8.0.4" />
+    <PackageReference Include="System.Text.Json" Version="8.0.5" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/Xledger.Collections/Extensions.cs b/Xledger.Collections/Extensions.cs
index 1184091..223eebd 100644
--- a/Xledger.Collections/Extensions.cs
+++ b/Xledger.Collections/Extensions.cs
@@ -12,6 +12,12 @@ public static ImmArray<T> ToImmArray<T>(this IEnumerable<T> xs) {
         };
     }
 
+#if NET
+    public static ImmArray<T> ToImmArray<T>(this ReadOnlySpan<T> xs) {
+        return new ImmArray<T>(xs.ToArray());
+    }
+#endif
+
     public static ImmSet<T> ToImmSet<T>(this IEnumerable<T> xs) {
         return xs switch {
             null => ImmSet<T>.Empty,
@@ -20,6 +26,12 @@ public static ImmSet<T> ToImmSet<T>(this IEnumerable<T> xs) {
         };
     }
 
+#if NET
+    public static ImmSet<T> ToImmSet<T>(this ReadOnlySpan<T> xs) {
+        return new ImmSet<T>(xs.ToArray());
+    }
+#endif
+
     public static ImmDict<K, V> ToImmDict<K, V>(this IEnumerable<KeyValuePair<K, V>> xs) {
         return xs switch {
             null => ImmDict<K, V>.Empty,
diff --git a/Xledger.Collections/ImmArray.cs b/Xledger.Collections/ImmArray.cs
index c62848c..9431b6a 100644
--- a/Xledger.Collections/ImmArray.cs
+++ b/Xledger.Collections/ImmArray.cs
@@ -4,11 +4,20 @@ public static class ImmArray {
     public static ImmArray<T> Of<T>(params T[] arr) {
         return arr.ToImmArray();
     }
+
+#if NET
+    public static ImmArray<T> Of<T>(ReadOnlySpan<T> span) {
+        return span.ToImmArray();
+    }
+#endif
 }
 
 [Serializable]
 [DebuggerDisplay("Count = {Count}")]
 [DebuggerTypeProxy(typeof(ImmArray<>.DebugView))]
+#if NET8_0_OR_GREATER
+[System.Runtime.CompilerServices.CollectionBuilder(typeof(ImmArray), nameof(ImmArray.Of))]
+#endif
 public sealed class ImmArray<T> : IReadOnlyList<T>, IEquatable<ImmArray<T>>, IList<T>,
     ICollection, IComparable, IComparable<ImmArray<T>>, IStructuralComparable
 {
diff --git a/Xledger.Collections/ImmSet.cs b/Xledger.Collections/ImmSet.cs
index 3be96cf..4495c77 100644
--- a/Xledger.Collections/ImmSet.cs
+++ b/Xledger.Collections/ImmSet.cs
@@ -4,11 +4,20 @@ public static class ImmSet {
     public static ImmSet<T> Of<T>(params T[] arr) {
         return arr.ToImmSet();
     }
+
+#if NET
+    public static ImmSet<T> Of<T>(ReadOnlySpan<T> span) {
+        return span.ToImmSet();
+    }
+#endif
 }
 
 [Serializable]
 [DebuggerDisplay("Count = {Count}")]
 [DebuggerTypeProxy(typeof(ImmSet<>.DebugView))]
+#if NET8_0_OR_GREATER
+[System.Runtime.CompilerServices.CollectionBuilder(typeof(ImmSet), nameof(ImmArray.Of))]
+#endif
 public sealed class ImmSet<T> : IReadOnlyCollection<T>, ISet<T>, IEquatable<ImmSet<T>>, ICollection
 #if NET6_0_OR_GREATER
     , IReadOnlySet<T>
diff --git a/Xledger.Collections/Xledger.Collections.csproj b/Xledger.Collections/Xledger.Collections.csproj
index 1bac6d2..8b7865a 100644
--- a/Xledger.Collections/Xledger.Collections.csproj
+++ b/Xledger.Collections/Xledger.Collections.csproj
@@ -5,7 +5,7 @@
     <RootNamespace>Xledger.Collections</RootNamespace>
     <AssemblyName>Xledger.Collections</AssemblyName>
 
-    <TargetFrameworks>net48;net6.0</TargetFrameworks>
+    <TargetFrameworks>net48;net6.0;net8.0</TargetFrameworks>
     <LangVersion>12.0</LangVersion>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>disable</Nullable>