Merge branch 'IxAsyncCSharp8' of https://github.com/dotnet/reactive into IxAsyncCSharp8

AUTHORS.txt

@@ -14,6 +14,7 @@ Arthur Watson
 Gert Drapers
 Mark Shields
 Eric Rozell
+Oren Novotny
 
 Rx.js and Ix.js:
 Matthew Podwysocki

Ix.NET/Source/System.Interactive.Async.Providers/System.Interactive.Async.Providers.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>Interactive Extensions Async Providers Library used to build query providers and express queries over async enumerable sequences.</Description>
     <AssemblyTitle>Interactive Extensions - Async Providers Library</AssemblyTitle>
-    <TargetFrameworks>net45;net46;netstandard2.0;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>net45;net46;netstandard2.0;netstandard2.1;netcoreapp3.0</TargetFrameworks>
     <PackageTags>Ix;Interactive;Extensions;Enumerable;Asynchronous</PackageTags>
   </PropertyGroup>
 
@@ -21,8 +21,4 @@
     <Compile Update="System\Linq\AsyncQueryableEx.Generated.cs" DesignTime="True" AutoGen="True" DependentUpon="AsyncQueryableEx.Generated.tt" />
   </ItemGroup>
 
-  <ItemGroup>
-    <Service Include="{508349b6-6b84-4df5-91f0-309beebad82d}" />
-  </ItemGroup>
-
 </Project>

Ix.NET/Source/System.Interactive.Async/System.Interactive.Async.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>Interactive Extensions Async Library used to express queries over asynchronous enumerable sequences.</Description>
     <AssemblyTitle>Interactive Extensions - Async Library</AssemblyTitle>
-    <TargetFrameworks>net45;net46;netstandard2.0;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>net45;net46;netstandard2.0;netstandard2.1;netcoreapp3.0</TargetFrameworks>
     <PackageTags>Ix;Interactive;Extensions;Enumerable;Asynchronous</PackageTags>
   </PropertyGroup>
 
@@ -22,9 +22,5 @@
   <ItemGroup>
     <ProjectReference Include="..\System.Linq.Async\System.Linq.Async.csproj" />
   </ItemGroup>
-
-  <ItemGroup>
-    <Folder Include="System\Threading\Tasks\" />
-  </ItemGroup>
   
 </Project>

Ix.NET/Source/System.Linq.Async.Queryable/System.Linq.Async.Queryable.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net45;net46;netstandard2.0;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>net45;net46;netstandard2.0;netstandard2.1;netcoreapp3.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>

Ix.NET/Source/System.Linq.Async/System.Linq.Async.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="MSBuild.Sdk.Extras">
 
   <PropertyGroup>
-    <TargetFrameworks>net45;net46;netstandard2.0;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>net45;net46;netstandard2.0;netstandard2.1;netcoreapp3.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>
@@ -18,7 +18,8 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Condition="'$(TargetFramework)' != 'netcoreapp3.0' " Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
+    <PackageReference Condition="'$(TargetFramework)' != 'netcoreapp3.0' and '$(TargetFramework)' != 'netstandard2.1' "
+                      Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
     <ReferenceAssemblyProjectReference Include="..\refs\System.Linq.Async.Ref\System.Linq.Async.Ref.csproj" />
   </ItemGroup>
 

Ix.NET/Source/refs/Directory.build.props

@@ -3,8 +3,6 @@
   <Import Project="..\Directory.Build.props" />
   
   <PropertyGroup>
-    <!-- This is here so we can create a fake .NET Standard 2.1 facade -->
-    <NETStandardMaximumVersion>2.1</NETStandardMaximumVersion>
     <DefineConstants>$(DefineConstants);REFERENCE_ASSEMBLY</DefineConstants>
   </PropertyGroup>
 

Ix.NET/Source/refs/System.Linq.Async.Ref/System.Linq.Async.Ref.csproj

@@ -4,12 +4,12 @@
     <Description>LINQ Standard Query Operators used to express queries over asynchronous enumerable sequences.</Description>
     <AssemblyTitle>System.Linq.Async</AssemblyTitle>
     <Authors>Microsoft</Authors>
-    <TargetFrameworks>net45;netstandard2.0;netcoreapp3.0</TargetFrameworks>
+    <TargetFrameworks>net45;netstandard2.0;netstandard2.1;netcoreapp3.0</TargetFrameworks>
     <PackageTags>Enumerable;Asynchronous;LINQ</PackageTags>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Condition="'$(TargetFramework)' != 'netcoreapp3.0' "
+    <PackageReference Condition="'$(TargetFramework)' != 'netcoreapp3.0' and '$(TargetFramework)' != 'netstandard2.1' "
                       Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
   </ItemGroup>
 

README.md

@@ -14,6 +14,17 @@ Catch us in the #rxnet channel over at http://reactiveui.net/slack
 ### Get nightly builds
 - NuGet v3 feed url (VS 2015+): `https://dotnet.myget.org/F/rx/api/v3/index.json`
 
+## System.Linq.Async / System.Interactive.Async / System.Interactive
+
+### v4.0 changes
+
+Ix Async 4.0 has a breaking change from prior versions due to being the first LINQ implementation
+to support the new C# 8 [async streams](https://github.com/dotnet/csharplang/blob/master/proposals/csharp-8.0/async-streams.md) feature. This means for .NET Standard 2.1 and .NET Core 3 targets, we use the in-box interfaces for `IAsyncEnumerable<T>` and friends. On other platforms, we provide the implementation, so you can use `await foreach` and create async iterators as you would expect. The types will unify to the system ones where the platform provides it.
+
+The code should be code-compatible, so recompiling should take care of most of it; note that binary compatibility will not work.
+
+## System.Reactive
+
 ### v4.0 changes
 Due to the [overwhelming](https://github.com/dotnet/reactive/issues/299) [pain](https://github.com/dotnet/reactive/issues/305) that fixing [#205 - Implement assembly version strategy](https://github.com/dotnet/reactive/issues/205) caused, we have refactored the libraries into a single library `System.Reactive`. To prevent breaking existing code that references the v3 libraries, we have facades with TypeForwarders to the new assembly. If you have a reference to a binary built against v3.0, then use the new `System.Reactive.Compatibility` package. 
 
@@ -97,7 +108,7 @@ Contributing
 
 ### Source code
 
-* Clone the sources: `git clone https://github.com/dotnet/reactive.git`
+* Clone the sources: `git clone https://github.com/dotnet/reactive`
 * [Building, testing and debugging the sources](https://github.com/dotnet/reactive/wiki/Building%20Testing%20and%20Debugging)
 
 ### Contribute!

azure-pipelines.ix.yml

@@ -1,4 +1,4 @@
-ntrigger:
+trigger:
   branches:
     include:
       - master
@@ -30,7 +30,7 @@ variables:
 steps:
 - task: DotNetCoreInstaller@0
   inputs:
-    version: '3.0.100-preview4-010374'
+    version: '3.0.100-preview4-010530'
 
 - task: DotNetCoreCLI@2  
   inputs: