Make ForwardingDirectory generic. (#74)
Due to an upcoming change in Dart 2.0
(https://github.com/dart-lang/sdk/issues/32148), it will no longer be
allowed for a class to implement the same generic interface in
different ways. (E.g. a class cannot implement/extend/mixin both
A<int> and A<String>).
This causes problems with _LocalDirectory. It extends
_LocalFileSystemEntity<_LocalDirectory, Directory>, which extends
ForwardingFileSystemEntity<_LocalDirectory, Directory>, but it mixes
in ForwardingDirectory, which extends
ForwardingFileSystemEntity<Directory, io.Directory>.
The solution is to make ForwardingDirectory a generic mixin, with
ForwardingDirectory<T> extending ForwardingFileSystemEntity<T,
io.Directory>. Type inference automatically fills in the type
argument T=_LocalDirectory at the site of the declaration of
_LocalDirectory.
diff --git a/lib/src/forwarding/forwarding_directory.dart b/lib/src/forwarding/forwarding_directory.dart
index 3c75a02..e49b9a7 100644
--- a/lib/src/forwarding/forwarding_directory.dart
+++ b/lib/src/forwarding/forwarding_directory.dart
@@ -5,11 +5,10 @@
part of file.src.forwarding;
/// A directory that forwards all methods and properties to a delegate.
-abstract class ForwardingDirectory
- extends ForwardingFileSystemEntity<Directory, io.Directory>
- implements Directory {
+abstract class ForwardingDirectory<T extends Directory>
+ extends ForwardingFileSystemEntity<T, io.Directory> implements Directory {
@override
- ForwardingDirectory wrap(io.Directory delegate) => wrapDirectory(delegate);
+ T wrap(io.Directory delegate) => wrapDirectory(delegate);
@override
Future<Directory> create({bool recursive: false}) async =>
