Initial commit

.editorconfig

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+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = space
+indent_size = 4
+trim_trailing_whitespace = true
+
+[*.{props,sln,targets}]
+indent_style = tab
+
+[*.{yml,yaml}]
+indent_size = 2
+

.gitattributes

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+* text=auto eol=lf
+*.sln text eol=crlf
+*.cs diff=csharp

.github/workflows/build.yml

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+name: Build
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions/setup-dotnet@v3
+    - name: Restore dependencies
+      run: dotnet restore /p:TreatWarningsAsErrors=true
+    - name: Build
+      run: dotnet build --no-restore /p:TreatWarningsAsErrors=true
+    - name: Run Tests
+      run: dotnet test --no-build
+  nupkg:
+    name: Generate NuGet Packages
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions/setup-dotnet@v3
+      name: Install Current .NET SDK
+    - name: Generate NuGet Packages
+      run: dotnet pack --configuration Release --output nupkg /p:TreatWarningsAsErrors=true
+    - uses: actions/upload-artifact@v2
+      if: success() && github.ref == 'refs/heads/main'
+      with:
+        name: nupkg
+        path: nupkg/*
+        retention-days: 1

.gitignore

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+bin/
+obj/

Directory.Build.props

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+<?xml version="1.0" encoding="utf-8"?>
+<Project>
+	<PropertyGroup Label="Shared NuGet Metadata">
+		<Authors>Polyadic</Authors>
+		<PackageLicenseExpression>MIT OR Apache-2.0</PackageLicenseExpression>
+		<PackageProjectUrl>https://github.com/polyadic/dispownership</PackageProjectUrl>
+		<Copyright>© Polyadic. All rights reserved.</Copyright>
+	</PropertyGroup>
+	<ItemGroup Label="Code Style">
+		<PackageReference Include="Messerli.CodeStyle" PrivateAssets="all" />
+	</ItemGroup>
+	<PropertyGroup Label="Deterministic Builds and Source Link">
+		<PublishRepositoryUrl>true</PublishRepositoryUrl>
+		<ContinuousIntegrationBuild Condition="'$(GITHUB_ACTIONS)' == 'true'">true</ContinuousIntegrationBuild>
+		<EmbedUntrackedSources>true</EmbedUntrackedSources>
+	</PropertyGroup>
+	<ItemGroup Label="Deterministic Builds and Source Link">
+		<PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All"/>
+	</ItemGroup>
+</Project>

Directory.Packages.props

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+<?xml version="1.0" encoding="utf-8"?>
+<Project>
+	<PropertyGroup>
+		<ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
+	</PropertyGroup>
+	<ItemGroup Label="Build Dependencies">
+		<PackageVersion Include="Messerli.CodeStyle" Version="2.2.0" />
+		<PackageVersion Include="Microsoft.SourceLink.GitHub" Version="1.1.1" />
+	</ItemGroup>
+	<ItemGroup Label="Test Dependencies">
+		<PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.2.0" />
+		<PackageVersion Include="xunit" Version="2.4.2" />
+		<PackageVersion Include="xunit.runner.visualstudio" Version="2.4.5" />
+	</ItemGroup>
+</Project>

Dispownership.Sources/Dispownership.Sources.csproj

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+<Project Sdk="Microsoft.Build.NoTargets/3.7.0">
+    <PropertyGroup>
+        <TargetFramework>netstandard2.0</TargetFramework>
+        <IncludeBuildOutput>false</IncludeBuildOutput>
+        <ContentTargetFolders>contentFiles</ContentTargetFolders>
+        <DisableImplicitFrameworkReferences>true</DisableImplicitFrameworkReferences>
+        <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
+        <GenerateTargetFrameworkAttribute>false</GenerateTargetFrameworkAttribute>
+        <SuppressDependenciesWhenPacking>true</SuppressDependenciesWhenPacking>
+        <LangVersion>11.0</LangVersion>
+    </PropertyGroup>
+    <ItemGroup>
+        <Compile Include="..\Dispownership\*.cs" Exclude="$(DefaultItemExcludes)" Link="%(FileName)%(Extension)" />
+    </ItemGroup>
+    <ItemGroup>
+        <Compile Update="@(Compile)">
+            <Pack>true</Pack>
+            <PackagePath>$(ContentTargetFolders)\cs\any\$(PackageId)\</PackagePath>
+        </Compile>
+    </ItemGroup>
+</Project>

Dispownership.Test/DisposableTest.cs

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+using System;
+using Xunit;
+
+namespace Dispownership.Test;
+
+public sealed class DisposableTest
+{
+    [Fact]
+    public void DisposesInnerValueIfOwned()
+    {
+#pragma warning disable IDISP001
+        var value = new DisposableStub();
+#pragma warning restore IDISP001
+
+        using (Disposable.Owned(value))
+        {
+        }
+
+        Assert.True(value.Disposed);
+    }
+
+    [Fact]
+    public void DoesNotDisposeInnerValueIfBorrowed()
+    {
+#pragma warning disable IDISP001
+        var value = new DisposableStub();
+#pragma warning restore IDISP001
+
+        using (Disposable.Borrowed(value))
+        {
+        }
+
+        Assert.False(value.Disposed);
+    }
+
+    [Fact]
+    public void DoesNotDisposeOwnedValueAfterMove()
+    {
+#pragma warning disable IDISP001
+        var value = new DisposableStub();
+#pragma warning restore IDISP001
+
+        using (var disposable = Disposable.Owned(value))
+        {
+            _ = disposable.Take();
+        }
+
+        Assert.False(value.Disposed);
+    }
+
+    [Fact]
+    public void ThrowsWhenMovingAValueTwice()
+    {
+#pragma warning disable IDISP004
+        using var disposable = Disposable.Owned(new DisposableStub());
+#pragma warning restore IDISP004
+        _ = disposable.Take();
+        Assert.Throws<InvalidOperationException>(() => disposable.Take());
+    }
+
+    [Fact]
+    public void ThrowsWhenMovingABorrowedValue()
+    {
+#pragma warning disable IDISP004
+        using var disposable = Disposable.Borrowed(new DisposableStub());
+#pragma warning restore IDISP004
+        Assert.Throws<InvalidOperationException>(() => disposable.Take());
+    }
+
+    private sealed class DisposableStub : IDisposable
+    {
+        public bool Disposed { get; private set; }
+
+        public void Dispose() => Disposed = true;
+    }
+}

Dispownership.Test/Dispownership.Test.csproj

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+<?xml version="1.0" encoding="utf-8"?>
+<Project Sdk="Microsoft.NET.Sdk">
+    <PropertyGroup>
+        <TargetFramework>net7.0</TargetFramework>
+        <IsPackable>false</IsPackable>
+    </PropertyGroup>
+    <ItemGroup>
+        <ProjectReference Include="..\Dispownership\Dispownership.csproj" />
+    </ItemGroup>
+    <ItemGroup>
+        <PackageReference Include="Microsoft.NET.Test.Sdk" />
+        <PackageReference Include="xunit" />
+        <PackageReference Include="xunit.runner.visualstudio" />
+    </ItemGroup>
+</Project>

Dispownership.sln

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+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dispownership", "Dispownership\Dispownership.csproj", "{0FC69541-37D7-4E58-A80B-2E8B8217A906}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dispownership.Sources", "Dispownership.Sources\Dispownership.Sources.csproj", "{B3926389-9766-4C06-ADDF-C46C0FFFDEE2}"
+EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{6FB7B031-CD30-4B19-A58C-23C4FE78FF0A}"
+	ProjectSection(SolutionItems) = preProject
+		.editorconfig = .editorconfig
+		.gitattributes = .gitattributes
+		.gitignore = .gitignore
+		readme.md = readme.md
+	EndProjectSection
+EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Build Config", "Build Config", "{688F10E7-1CEB-412E-A9A8-8BD16F2BDED5}"
+	ProjectSection(SolutionItems) = preProject
+		Directory.Build.props = Directory.Build.props
+		Directory.Packages.props = Directory.Packages.props
+		global.json = global.json
+		NuGet.config = NuGet.config
+	EndProjectSection
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dispownership.Test", "Dispownership.Test\Dispownership.Test.csproj", "{A1F6A514-4CC2-49E8-B4CF-D731692EE463}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{0FC69541-37D7-4E58-A80B-2E8B8217A906}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{0FC69541-37D7-4E58-A80B-2E8B8217A906}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{0FC69541-37D7-4E58-A80B-2E8B8217A906}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{0FC69541-37D7-4E58-A80B-2E8B8217A906}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B3926389-9766-4C06-ADDF-C46C0FFFDEE2}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B3926389-9766-4C06-ADDF-C46C0FFFDEE2}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B3926389-9766-4C06-ADDF-C46C0FFFDEE2}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B3926389-9766-4C06-ADDF-C46C0FFFDEE2}.Release|Any CPU.Build.0 = Release|Any CPU
+		{A1F6A514-4CC2-49E8-B4CF-D731692EE463}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{A1F6A514-4CC2-49E8-B4CF-D731692EE463}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{A1F6A514-4CC2-49E8-B4CF-D731692EE463}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{A1F6A514-4CC2-49E8-B4CF-D731692EE463}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal

Dispownership/AsyncDisposable.cs

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+#pragma warning disable SA1201
+#pragma warning disable IDE0005 // Disable unused usings warning if enabled in consuming project
+
+#if (NETSTANDARD2_1 || NET5_0_OR_GREATER) && DISPOWNERSHIP_ASYNC
+using System;
+using System.Threading.Tasks;
+
+namespace Dispownership;
+
+#if DISPOWNERSHIP_VISIBILITY_PUBLIC
+public
+#else
+internal
+#endif
+static class AsyncDisposable
+{
+    /// <summary>Creates a owned wrapper around a disposable i.e. the disposable will be disposed when the wrapper is disposed.</summary>
+    public static AsyncDisposable<TDisposable> Owned<TDisposable>(TDisposable value)
+        where TDisposable : IAsyncDisposable
+        => new(value, hasOwnership: true);
+
+    /// <summary>Creates a borrowing wrapper around a disposable i.e. the disposable will not be disposed when the wrapper is disposed.</summary>
+    public static AsyncDisposable<TDisposable> Borrowed<TDisposable>(TDisposable value)
+        where TDisposable : IAsyncDisposable
+        => new(value, hasOwnership: false);
+}
+
+/// <summary>A wrapper around an <see cref="IAsyncDisposable"/> that either owns or borrows the value.
+/// Use <see cref="AsyncDisposable.Owned{TDisposable}"/> or <see cref="AsyncDisposable.Borrowed{TDisposable}"/> to create an instance of this wrapper.</summary>
+#if DISPOWNERSHIP_VISIBILITY_PUBLIC
+public
+#else
+internal
+#endif
+struct AsyncDisposable<TDisposable> : IAsyncDisposable
+    where TDisposable : IAsyncDisposable
+{
+    private readonly TDisposable _inner;
+    private bool _hasOwnership;
+
+    internal AsyncDisposable(TDisposable inner, bool hasOwnership)
+    {
+        _inner = inner;
+        _hasOwnership = hasOwnership;
+    }
+
+    public TDisposable Value => _inner;
+
+    /// <summary>Consumes the value leaving this wrapper without ownership.
+    /// This is useful in scenarios where you want to create a disposable, do some work that might fail and then return it.</summary>
+    /// <exception cref="InvalidOperationException">Thrown when this instance does not have ownership over the disposable.</exception>
+    public TDisposable Take()
+    {
+        if (!_hasOwnership)
+        {
+            throw new InvalidOperationException(
+                $"Value can only be consumed when owned. " +
+                $"This error may occur if you call {nameof(Take)} more than once");
+        }
+
+        _hasOwnership = false;
+        return _inner;
+    }
+
+#pragma warning disable IDISP007
+    public ValueTask DisposeAsync()
+        => _hasOwnership
+            ? (_inner?.DisposeAsync() ?? default)
+            : default;
+#pragma warning restore IDISP007
+}
+#endif