added a simple test that creates a full PS Runspace and executes a script

scripts/Makefile

@@ -194,7 +194,7 @@ native-tests: dotnetlibs/monad_native
 
 xunit-tests: $(RUN_TARGETS) internal-prepare-exec_env internal-prepare-release-clr $(addprefix $(TESTRUN_FOLDER)/, ps_test.dll xunit.console.netcore.exe xunit.runner.utility.dll xunit.abstractions.dll xunit.execution.dll)
 	# execute the xUnit runner, with XML output
-	cd exec_env/app_base && PSMODULEPATH=$(shell pwd)/exec_env/app_base/Modules LD_LIBRARY_PATH=../coreclr:. ../coreclr/corerun xunit.console.netcore.exe ps_test.dll -xml ../../xunittests.xml
+	exec_env/app_base/runps-test.sh ps_test.dll -xml ../../xunittests.xml
 
 pester-tests: $(RUN_TARGETS) internal-prepare-exec_env internal-prepare-release-clr
 	# execute the Pester tests, which needs a TEMP environment variable to be set

scripts/runps-test.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+CWD=$(pwd)
+SCRIPTDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+
+cd "$SCRIPTDIR"
+PSMODULEPATH="$SCRIPTDIR/Modules" LD_LIBRARY_PATH="$SCRIPTDIR" ./host_cmdline -c ../coreclr -alc Microsoft.PowerShell.CoreCLR.AssemblyLoadContext.dll -tpa xunit.console.netcore.exe xunit.console.netcore.exe "$@"

src/ps_test/test_Runspace.cs

@@ -0,0 +1,48 @@
+using Xunit;
+using System;
+using System.Management.Automation;
+using System.Management.Automation.Runspaces;
+
+namespace PSTests
+{
+    public static class RunspaceTests
+    {
+        [Fact]
+        public static void TestMethod()
+        {
+            InitialSessionState iss = InitialSessionState.CreateDefault2();
+
+            // NOTE: instantiate custom host myHost for the next line to capture stdout and stderr output
+            //       in addition to just the PSObjects
+            using (Runspace rs = RunspaceFactory.CreateRunspace(/*myHost,*/iss))
+            {
+                rs.Open();
+                using (PowerShell ps = PowerShell.Create())
+                {
+                    ps.Runspace = rs;
+
+                    string script = "get-process | select-object -first 3";
+                    ps.AddScript(script);
+
+                    // IMPORTANT NOTE: do not call AddCommand("out-host") here or
+                    // MergeMyResults, otherwise Invoke will not return any objects
+                    
+                    var results = ps.Invoke();
+
+                    // check that there are 3 captured objects
+                    int objCount = 0;
+                    foreach (var result in results)
+                    {
+                        // this is how an object would be captured here and looked at,
+                        // each result is a PSObject with the data from the pipeline
+                        ++objCount;
+                        Assert.NotNull(result);
+                    }
+                    Assert.Equal(3,objCount);
+                    ps.Dispose();
+                }
+            }
+        }
+    }
+}
+