Switch from using SafeHandle for Unix enumeration (#27052)

* Switch from using SafeHandle for Unix enumeration

* Address feedback

* Fix faceplant, dispose in test.

2 files changed, 44 insertions, 0 deletions

diff --git a/src/System.IO.FileSystem/tests/Enumeration/ErrorHandlingTests.netcoreapp.cs b/src/System.IO.FileSystem/tests/Enumeration/ErrorHandlingTests.netcoreapp.cs
new file mode 100644
index 0000000000..24f07f8911
--- /dev/null
+++ b/src/System.IO.FileSystem/tests/Enumeration/ErrorHandlingTests.netcoreapp.cs
@@ -0,0 +1,43 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.IO.Enumeration;
+using Xunit;
+
+namespace System.IO.Tests
+{
+    public class ErrorHandlingTests : FileSystemTest
+    {
+        private class IgnoreErrors : FileSystemEnumerator<string>
+        {
+            public IgnoreErrors(string directory)
+                : base(directory)
+            { }
+
+            public int ErrorCount { get; private set; }
+
+            protected override string TransformEntry(ref FileSystemEntry entry)
+            {
+                throw new NotImplementedException();
+            }
+
+            protected override bool ContinueOnError(int error)
+            {
+                ErrorCount++;
+                return true;
+            }
+        }
+
+        [Fact]
+        public void OpenErrorDoesNotHappenAgainOnMoveNext()
+        {
+            using (IgnoreErrors ie = new IgnoreErrors(Path.GetRandomFileName()))
+            {
+                Assert.Equal(1, ie.ErrorCount);
+                Assert.False(ie.MoveNext());
+                Assert.Equal(1, ie.ErrorCount);
+            }
+        }
+    }
+}
diff --git a/src/System.IO.FileSystem/tests/System.IO.FileSystem.Tests.csproj b/src/System.IO.FileSystem/tests/System.IO.FileSystem.Tests.csproj
index 471bf4cd52..63a4b2c7cf 100644
--- a/src/System.IO.FileSystem/tests/System.IO.FileSystem.Tests.csproj
+++ b/src/System.IO.FileSystem/tests/System.IO.FileSystem.Tests.csproj
@@ -59,6 +59,7 @@
     <Compile Include="Enumeration\DosMatcherTests.netcoreapp.cs" />
     <Compile Include="Enumeration\MatchCasingTests.netcoreapp.cs" />
     <Compile Include="Enumeration\TrimmedPaths.netcoreapp.cs" />
+    <Compile Include="Enumeration\ErrorHandlingTests.netcoreapp.cs" />
   </ItemGroup>
   <ItemGroup>
     <!-- Rewritten -->