Sealed Windows FileTypeExt extensible trait broke FileTypeExt in wasi-common #102260
Description
EDIT: So Sealing happened via 2nd commit on: #98583 - which I had originally traced down here but didn't have PR ref
Unknowns / TODO
Note: I can't find windows_file_type_ext feature from unstable book or it's tracking issue ?
So the Sealed trait was designed to prevent people rolling own trait impl's ?
I suspect that cap-primitives may need to deal with the Sealed trait instead of rolling own trait / impl like it's done now ?
But I think that may be troublematic.. going by guessing what was intended in cap-primitives
Don't know yet enough about the sealed feature (yet) as it doesn't seem to have much docs around and I need to dig deeper on this.
Issue
On Windows builds that rely on wasi-common on which we rely on at lunatic:
wasi-common v0.40.0
├── cap-std v0.25.2
├── cap-primitives v0.25.2
We now get via cap-primitives this in 1.66.0-nightly (4a14677 2022-09-23):
error[E0277]: the trait bound file_type::FileType: std::sealed::Sealed is not satisfied
<snip>
|
134 | impl std::os::windows::fs::FileTypeExt for FileType {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait std::sealed::Sealed is not implemented for file_type::FileType
|
<snip>
error: could not compile cap-primitives due to previous error
warning: build failed, waiting for other jobs to finish...
error: failed to compile lunatic-runtime v0.10.0, intermediate artifacts can be found at <snip>
Now this was probably very intentional but
Sealed
So Sealed acts as some kind of guard for the ecosystem not to mess with it ?
mod sealed {
/// This trait being unreachable from outside the crate
/// prevents outside implementations of our extension traits.
/// This allows adding more trait methods in the future.
#[unstable(feature = "sealed", issue = "none")]
pub trait Sealed {}
}Related earlier changes
I see the below changes re: stabilisation related to feature windows_file_type_ext
library/std/src/os/windows/fs.rs 2022-06-27 09:57:56 -0700 10) use crate::sealed::Sealed;
library/std/src/os/windows/fs.rs 2022-06-27 09:41:12 -0700 506) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
library/std/src/os/windows/fs.rs 2022-06-27 09:57:56 -0700 507) pub trait FileTypeExt: Sealed {
wasi/cap-primitives Related
This works okay in OSX, Linux but Windows builds are now broken with this where the error comes from:
cap-primitives/src/fs/file_type.rs - https://docs.rs/cap-primitives/latest/src/cap_primitives/fs/file_type.rs.html#125-147
/// Windows-specific extensions for [`FileType`].
///
/// This corresponds to [`std::os::windows::fs::FileTypeExt`].
#[cfg(all(windows, windows_file_type_ext))]
pub trait FileTypeExt {
/// Returns `true` if this file type is a symbolic link that is also a directory.
fn is_symlink_dir(&self) -> bool;
/// Returns `true` if this file type is a symbolic link that is also a file.
fn is_symlink_file(&self) -> bool;
}
#[cfg(all(windows, windows_file_type_ext))]
impl FileTypeExt for FileType {
#[inline]
fn is_symlink_dir(&self) -> bool {
self.0 == Inner::Ext(ImplFileTypeExt::symlink_dir())
}
#[inline]
fn is_symlink_file(&self) -> bool {
self.0 == Inner::Ext(ImplFileTypeExt::symlink_file())
}
}git b
0a96e089bade library/std/src/sys/windows/ext/fs.rs (Prabakaran Kumaresshan 2020-08-16 22:28:45 +0530 503) /// Windows-specific extensions to [`fs::FileType`].
182d99cfd1a5 src/libstd/sys/windows/ext/fs.rs (Dylan MacKenzie 2018-04-09 17:44:28 -0700 504) ///
182d99cfd1a5 src/libstd/sys/windows/ext/fs.rs (Dylan MacKenzie 2018-04-09 17:44:28 -0700 505) /// On Windows, a symbolic link knows whether it is a file or directory.
e374c911af9a library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:41:12 -0700 506) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
a4cb0b90c049 library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:57:56 -0700 507) pub trait FileTypeExt: Sealed {
99ed06eb8864 src/libstd/sys/windows/ext/fs.rs (Alexander Regueiro 2019-02-09 22:16:58 +0000 508) /// Returns `true` if this file type is a symbolic link that is also a directory.
e374c911af9a library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:41:12 -0700 509) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 510) fn is_symlink_dir(&self) -> bool;
99ed06eb8864 src/libstd/sys/windows/ext/fs.rs (Alexander Regueiro 2019-02-09 22:16:58 +0000 511) /// Returns `true` if this file type is a symbolic link that is also a file.
e374c911af9a library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:41:12 -0700 512) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 513) fn is_symlink_file(&self) -> bool;
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 514) }
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 515)
a4cb0b90c049 library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:57:56 -0700 516) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
a4cb0b90c049 library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:57:56 -0700 517) impl Sealed for fs::FileType {}
a4cb0b90c049 library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:57:56 -0700 518)
e374c911af9a library/std/src/os/windows/fs.rs (Josh Triplett 2022-06-27 09:41:12 -0700 519) #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 520) impl FileTypeExt for fs::FileType {
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 521) fn is_symlink_dir(&self) -> bool {
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 522) self.as_inner().is_symlink_dir()
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 523) }
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 524) fn is_symlink_file(&self) -> bool {
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 525) self.as_inner().is_symlink_file()
c34fbfaad38c src/libstd/sys/windows/ext/fs.rs (David Tolnay 2019-11-27 10:28:39 -0800 526) }
9269e83b37e8 src/libstd/sys/windows/ext/fs.rs (Peter Atashian 2018-02-11 13:40:46 -0500 527) }
Refs
https://docs.rs/cap-primitives/latest/src/cap_primitives/fs/file_type.rs.html#125-147
https://github.com/bytecodealliance/cap-std
https://doc.rust-lang.org/std/os/windows/fs/trait.FileTypeExt.html
https://stdrs.dev/nightly/x86_64-unknown-linux-gnu/std/sealed/trait.Sealed.html
https://stdrs.dev/nightly/x86_64-unknown-linux-gnu/std/sealed/trait.Sealed.html
lunatic-solutions/lunatic#136