Build NetCoreApp2.1 test project with .NET Core SDK 2.1

build.json

@@ -2,6 +2,7 @@
     "DotNetInstallScriptURL": "https://dot.net/v1",
     "DotNetChannel": "Preview",
     "DotNetVersions": [
+        "2.1.811",
         "3.1.403",
         "5.0.100"
     ],
@@ -44,6 +45,7 @@
         "ProjectWithDisabledAnalyzers2",
         "ProjectWithAnalyzers",
         "NetCore21Project",
+        "NetCore31Project",
         "Net50Project",
         "ProjectWithAnalyzersAndEditorConfig",
         "ProjectWithParentEditorConfig"

test-assets/test-projects/NetCore21Project/global.json

@@ -0,0 +1,5 @@
+{
+    "sdk": {
+        "version": "2.1.811"
+    }
+}

test-assets/test-projects/NetCore31Project/NetCore31Project.csproj

@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>

test-assets/test-projects/NetCore31Project/Program.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace ProjectAndSolution
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("Hello World!");
+        }
+    }
+}

test-assets/test-projects/NetCore31Project/global.json

@@ -0,0 +1,5 @@
+{
+    "sdk": {
+        "version": "3.1.403"
+    }
+}

tests/OmniSharp.MSBuild.Tests/ProjectLoadListenerTests.cs

@@ -185,23 +185,35 @@ public async Task The_correct_project_capablities_is_emitted()
             using var testProject = await TestAssets.Instance.GetTestProjectAsync("NetCore21Project");
             using var host = CreateMSBuildTestHost(testProject.Directory, emitter.AsExportDescriptionProvider(LoggerFactory));
             Assert.Single(emitter.ReceivedMessages);
-            Assert.Equal("GenerateDocumentationFile CSharp Managed ReferencesFolder LanguageService RelativePathDerivedDefaultNamespace AssemblyReferences COMReferences ProjectReferences SharedProjectReferences OutputGroups AllTargetOutputGroups VisualStudioWellKnownOutputGroups SingleFileGenerators DeclaredSourceItems UserSourceItems BuildWindowsDesktopTarget CrossPlatformExecutable Pack", string.Join(" ", emitter.ReceivedMessages[0].ProjectCapabilities));
+            Assert.Equal("GenerateDocumentationFile CSharp Managed ReferencesFolder LanguageService RelativePathDerivedDefaultNamespace AssemblyReferences COMReferences ProjectReferences SharedProjectReferences OutputGroups AllTargetOutputGroups VisualStudioWellKnownOutputGroups SingleFileGenerators DeclaredSourceItems UserSourceItems BuildWindowsDesktopTarget CrossPlatformExecutable FolderPublish Pack", string.Join(" ", emitter.ReceivedMessages[0].ProjectCapabilities));
         }
 
         [Fact]
-        public async Task The_correct_sdk_version_is_emitted()
+        public async Task The_correct_sdk_version_is_emitted_NETCore2_1()
         {
             // Arrange
             var emitter = new ProjectLoadTestEventEmitter();
 
             using var testProject = await TestAssets.Instance.GetTestProjectAsync("NetCore21Project");
             using var host = CreateMSBuildTestHost(testProject.Directory, emitter.AsExportDescriptionProvider(LoggerFactory));
             Assert.Single(emitter.ReceivedMessages);
+            Assert.Equal(GetHashedFileExtension("2.1.811"), emitter.ReceivedMessages[0].SdkVersion);
+        }
+
+        [Fact]
+        public async Task The_correct_sdk_version_is_emitted_NETCore3_1()
+        {
+            // Arrange
+            var emitter = new ProjectLoadTestEventEmitter();
+
+            using var testProject = await TestAssets.Instance.GetTestProjectAsync("NetCore31Project");
+            using var host = CreateMSBuildTestHost(testProject.Directory, emitter.AsExportDescriptionProvider(LoggerFactory));
+            Assert.Single(emitter.ReceivedMessages);
             Assert.Equal(GetHashedFileExtension("3.1.403"), emitter.ReceivedMessages[0].SdkVersion);
         }
 
         [Fact]
-        public async Task The_correct_sdk_version_is_emitted_2()
+        public async Task The_correct_sdk_version_is_emitted_NET5()
         {
             // Arrange
             var emitter = new ProjectLoadTestEventEmitter();