Simplify target paths by leveraging newest dir behavior in dotnet-file

The trailing '/' on the URL now means "construct target path from here on", so we don't get duplicated directory structure.

src/Core/Interop/src/shared/Core/Interop/src/shared/Core/Interop/MacOS/MacOSKeychain.cs → src/Core/Interop/MacOS/MacOSKeychain.cs

@@ -66,6 +66,7 @@ public IList<string> GetAccounts(string service)
                         if (typeId == CFArrayGetTypeID())
                         {
                             int len = (int)CFArrayGetCount(resultPtr);
+                            // NOTE: removed len from HashSet ctor since it's not supported in NS2.0
                             var accounts = new HashSet<string>();
                             for (int i = 0; i < len; i++)
                             {

src/Core/Interop/Posix/PosixFileSystem.Custom.cs

@@ -0,0 +1,35 @@
+namespace GitCredentialManager.Interop.Posix;
+
+// NOTE: delete the existing TryResolve* in the sync'ed file, make the class partial, 
+// and this implementation will fix the build when upgrading. Note that links will 
+// actually not be supported.
+partial class PosixFileSystem
+{
+#if NETSTANDARD2_0
+    private static bool TryResolveFileLink(string path, out string target)
+    {
+        target = null;
+        return false;
+    }
+
+    private static bool TryResolveDirectoryLink(string path, out string target)
+    {
+        target = null;
+        return false;
+    }
+#elif !NETFRAMEWORK
+        private static bool TryResolveFileLink(string path, out string target)
+        {
+            FileSystemInfo fsi = Polyfills.FileResolveLinkTarget(path, true);
+            target = fsi?.FullName;
+            return fsi != null;
+        }
+
+        private static bool TryResolveDirectoryLink(string path, out string target)
+        {
+            FileSystemInfo fsi = Polyfills.DirectoryResolveLinkTarget(path, true);
+            target = fsi?.FullName;
+            return fsi != null;
+        }
+#endif
+}

src/Core/Interop/src/shared/Core/Interop/src/shared/Core/Interop/Posix/PosixFileSystem.cs → src/Core/Interop/Posix/PosixFileSystem.cs

@@ -3,7 +3,7 @@
 
 namespace GitCredentialManager.Interop.Posix
 {
-    public abstract class PosixFileSystem : FileSystem
+    public abstract partial class PosixFileSystem : FileSystem
     {
         /// <summary>
         /// Recursively resolve a symbolic link.
@@ -56,33 +56,5 @@ protected internal static string ResolveSymbolicLinks(string path)
             return Path.Combine("/", partialPath);
 #endif
         }
-
-#if NETSTANDARD2_0
-        private static bool TryResolveFileLink(string path, out string target)
-        {
-            target = null;
-            return false;
-        }
-
-        private static bool TryResolveDirectoryLink(string path, out string target)
-        {
-            target = null;
-            return false;
-        }
-#elif !NETFRAMEWORK
-        private static bool TryResolveFileLink(string path, out string target)
-        {
-            FileSystemInfo fsi = File.ResolveLinkTarget(path, true);
-            target = fsi?.FullName;
-            return fsi != null;
-        }
-
-        private static bool TryResolveDirectoryLink(string path, out string target)
-        {
-            FileSystemInfo fsi = Directory.ResolveLinkTarget(path, true);
-            target = fsi?.FullName;
-            return fsi != null;
-        }
-#endif
     }
 }