Add test for order of raising AssemblyLoadContext.Unloading and AppDomain.ProcessExit

coreclr PR: https://github.com/dotnet/coreclr/pull/8737

2 files changed, 38 insertions, 0 deletions

diff --git a/src/System.Runtime.Extensions/tests/System.Runtime.Extensions.Tests.csproj b/src/System.Runtime.Extensions/tests/System.Runtime.Extensions.Tests.csproj
index ffdffdc7a8..a1d0c67a46 100644
--- a/src/System.Runtime.Extensions/tests/System.Runtime.Extensions.Tests.csproj
+++ b/src/System.Runtime.Extensions/tests/System.Runtime.Extensions.Tests.csproj
@@ -55,6 +55,7 @@
     <Compile Include="System\IO\Path.GetRelativePath.cs" />
     <Compile Include="System\MathTests.netcoreapp1.1.cs" />
     <Compile Include="System\MathF.netcoreapp1.1.cs" />
+    <Compile Include="System\UnloadingAndProcessExitTests.netcoreapp1.1.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="System\Diagnostics\Stopwatch.cs" />
diff --git a/src/System.Runtime.Extensions/tests/System/UnloadingAndProcessExitTests.netcoreapp1.1.cs b/src/System.Runtime.Extensions/tests/System/UnloadingAndProcessExitTests.netcoreapp1.1.cs
new file mode 100644
index 0000000000..49b10b0fe3
--- /dev/null
+++ b/src/System.Runtime.Extensions/tests/System/UnloadingAndProcessExitTests.netcoreapp1.1.cs
@@ -0,0 +1,37 @@
+using System.Diagnostics;
+using System.IO;
+using System.Threading;
+using Xunit;
+
+namespace System.Tests
+{
+    public class UnloadingAndProcessExitTests : RemoteExecutorTestBase
+    {
+        [Fact]
+        public void UnloadingEventMustHappenBeforeProcessExitEvent()
+        {
+            string fileName = GetTestFilePath();
+
+            File.WriteAllText(fileName, string.Empty);
+
+            Func<string, int> otherProcess = f =>
+            {
+                Action<int> OnUnloading = i => File.AppendAllText(f, string.Format("u{0}", i));
+                Action<int> OnProcessExit = i => File.AppendAllText(f, string.Format("e{0}", i));
+
+                AppDomain.CurrentDomain.ProcessExit += (sender, e) => OnProcessExit(0);
+                System.Runtime.Loader.AssemblyLoadContext.Default.Unloading += acl => OnUnloading(0);
+                AppDomain.CurrentDomain.ProcessExit += (sender, e) => OnProcessExit(1);
+                System.Runtime.Loader.AssemblyLoadContext.Default.Unloading += acl => OnUnloading(1);
+
+                return SuccessExitCode;
+            };
+
+            using (var remote = RemoteInvoke(otherProcess, fileName))
+            {
+            }
+
+            Assert.Equal(File.ReadAllText(fileName), "u0u1e0e1");
+        }
+    }
+}