Allow copying/moving/replacing broken symlinks

2 files changed, 34 insertions, 0 deletions

diff --git a/src/System.IO.FileSystem/tests/File/Copy.cs b/src/System.IO.FileSystem/tests/File/Copy.cs
index 81338ceb91..2cf108e8db 100644
--- a/src/System.IO.FileSystem/tests/File/Copy.cs
+++ b/src/System.IO.FileSystem/tests/File/Copy.cs
@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using Xunit;
+using System.Runtime.InteropServices;
 
 namespace System.IO.Tests
 {
@@ -48,6 +49,22 @@ namespace System.IO.Tests
             Assert.Throws<IOException>(() => Copy(testFile, testFile));
         }
 
+        [DllImport("libc", SetLastError = true)]
+        private static extern int symlink(string target, string linkpath);
+
+        [Fact]
+        [PlatformSpecific(TestPlatforms.AnyUnix)]
+        public void DanglingSymlinkCopy()
+        {
+            string dangling_symlink = GetTestFileName();
+            string missing_target = GetTestFileName();
+            string dangling_symlink_new_location = GetTestFileName();
+            Assert.False(File.Exists(missing_target));
+            Assert.Equal(symlink(missing_target, dangling_symlink), 0);
+            Copy(dangling_symlink, dangling_symlink_new_location);
+            Assert.True(File.Exists(dangling_symlink_new_location)); // File.Exists returns true for dangling symlinks
+        }
+
         [Fact]
         [SkipOnTargetFramework(TargetFrameworkMonikers.Mono, "CoreFX FileStream not yet imported")]
         public void NonExistentPath()
diff --git a/src/System.IO.FileSystem/tests/File/Move.cs b/src/System.IO.FileSystem/tests/File/Move.cs
index e9da920edd..6548b4f564 100644
--- a/src/System.IO.FileSystem/tests/File/Move.cs
+++ b/src/System.IO.FileSystem/tests/File/Move.cs
@@ -4,6 +4,7 @@
 
 using Xunit;
 using System.Linq;
+using System.Runtime.InteropServices;
 
 namespace System.IO.Tests
 {
@@ -174,6 +175,22 @@ namespace System.IO.Tests
             Assert.False(File.Exists(testFileSource.FullName));
         }
 
+        [DllImport("libc", SetLastError = true)]
+        private static extern int symlink(string target, string linkpath);
+
+        [Fact]
+        [PlatformSpecific(TestPlatforms.AnyUnix)]
+        public void DanglingSymlinkMove()
+        {
+            string dangling_symlink = GetTestFileName();
+            string missing_target = GetTestFileName();
+            string dangling_symlink_new_location = GetTestFileName();
+            Assert.False(File.Exists(missing_target));
+            Assert.Equal(symlink(missing_target, dangling_symlink), 0);
+            Move(dangling_symlink, dangling_symlink_new_location);
+            Assert.True(File.Exists(dangling_symlink_new_location)); // File.Exists returns true for dangling symlinks
+        }
+
         [Fact]
         public void FileNameWithSignificantWhitespace()
         {