CLI Testing via msbuild (#3779)

* Rebase

* Remove Multi-Project Validator

* Remove projectmodelserver tests

* Enable test package creation

* Incremental test restore

* WiP

* Enable Test Asset Project restore

* Build Test Assets & Restore Test Projects

* Build Test projects

* Enable Test Execution

also moves Test Targets to a well-known CLI Version [Stage 2]

* Pass throuh existing telemetry profile

* 2-space tabs

* Revert TestTargets.cs

* WiP PR feedback

* Refactoring

* Fix naming of RestoreTestAssetPackages

* DotNetTest task

* Fix merge issue

* ExecuteWithCapturedOutput

MSBuild considers StdErr output to be failures. This causes output of any test command which is expected to produce an error to be swallowed in the test.

* Workaround for always-on tracing functionality in dotnet-test

* Fix Path Separator Windows/Unix

* Seperate package build from pack

* Windows Pathing issues

* PR Feedback

* Workaround for msbuild #773

https://github.com/Microsoft/msbuild/issues/773

build_projects/dotnet-cli-build/DotNetTool.cs

@@ -80,4 +80,53 @@ namespace Microsoft.DotNet.Cli.Build
             return null;
         }
     }
+
+    public class DotNetTest : DotNetTool
+    {
+        protected override string Command
+        {
+            get { return "test"; }
+        }
+
+        protected override string Args
+        {
+            get { return $"{GetConfiguration()} {GetXml()} {GetNoTrait()}"; }
+        }
+
+        public string Configuration { get; set; }
+
+        public string Xml { get; set; }
+
+        public string NoTrait { get; set; }
+
+        private string GetConfiguration()
+        {
+            if (!string.IsNullOrEmpty(Configuration))
+            {
+                return $"--configuration {Configuration}";
+            }
+
+            return null;
+        }
+
+        private string GetNoTrait()
+        {
+            if (!string.IsNullOrEmpty(Configuration))
+            {
+                return $"-notrait {NoTrait}";
+            }
+
+            return null;
+        }
+
+        private string GetXml()
+        {
+            if (!string.IsNullOrEmpty(Xml))
+            {
+                return $"-xml {Xml}";
+            }
+
+            return null;
+        }
+    }
 }