From bfd1ccfb271f03aa85488408c3b03a15ad8d7c7f Mon Sep 17 00:00:00 2001 From: Amanieu d'Antras Date: Wed, 10 Feb 2021 21:30:30 +0000 Subject: [PATCH] Seal the CommandExt, OsStrExt and OsStringExt traits --- library/std/src/ffi/os_str.rs | 8 ++++++++ library/std/src/lib.rs | 8 ++++++++ library/std/src/process.rs | 8 ++++++++ library/std/src/sys/unix/ext/process.rs | 19 ++++++------------- library/std/src/sys/windows/ext/ffi.rs | 11 +++++++++-- library/std/src/sys/windows/ext/process.rs | 19 ++++++------------- library/std/src/sys_common/os_str_bytes.rs | 11 +++++++++-- 7 files changed, 54 insertions(+), 30 deletions(-) diff --git a/library/std/src/ffi/os_str.rs b/library/std/src/ffi/os_str.rs index c9c8f68cd9cce..5bb3f6bdcfd7b 100644 --- a/library/std/src/ffi/os_str.rs +++ b/library/std/src/ffi/os_str.rs @@ -76,6 +76,10 @@ pub struct OsString { inner: Buf, } +/// Allows extension traits within `std`. +#[unstable(feature = "sealed", issue = "none")] +impl crate::sealed::Sealed for OsString {} + /// Borrowed reference to an OS string (see [`OsString`]). /// /// This type represents a borrowed reference to a string in the operating system's preferred @@ -100,6 +104,10 @@ pub struct OsStr { inner: Slice, } +/// Allows extension traits within `std`. +#[unstable(feature = "sealed", issue = "none")] +impl crate::sealed::Sealed for OsStr {} + impl OsString { /// Constructs a new empty `OsString`. /// diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs index 961cff661e3ba..d5e00ae4be659 100644 --- a/library/std/src/lib.rs +++ b/library/std/src/lib.rs @@ -582,3 +582,11 @@ include!("keyword_docs.rs"); // is unconditional, so the unstable feature needs to be defined somewhere. #[unstable(feature = "restricted_std", issue = "none")] mod __restricted_std_workaround {} + +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 {} +} diff --git a/library/std/src/process.rs b/library/std/src/process.rs index fb78e62834a07..6480e654c55f0 100644 --- a/library/std/src/process.rs +++ b/library/std/src/process.rs @@ -498,6 +498,10 @@ pub struct Command { inner: imp::Command, } +/// Allows extension traits within `std`. +#[unstable(feature = "sealed", issue = "none")] +impl crate::sealed::Sealed for Command {} + impl Command { /// Constructs a new `Command` for launching the program at /// path `program`, with the following default configuration: @@ -1375,6 +1379,10 @@ impl From for Stdio { #[stable(feature = "process", since = "1.0.0")] pub struct ExitStatus(imp::ExitStatus); +/// Allows extension traits within `std`. +#[unstable(feature = "sealed", issue = "none")] +impl crate::sealed::Sealed for ExitStatus {} + impl ExitStatus { /// Was termination successful? Signal termination is not considered a /// success, and success is defined as a zero exit status. diff --git a/library/std/src/sys/unix/ext/process.rs b/library/std/src/sys/unix/ext/process.rs index 724b5dcca6a36..7559c1f1d9e29 100644 --- a/library/std/src/sys/unix/ext/process.rs +++ b/library/std/src/sys/unix/ext/process.rs @@ -6,20 +6,16 @@ use crate::ffi::OsStr; use crate::io; use crate::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd}; use crate::process; +use crate::sealed::Sealed; use crate::sys; use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner}; -mod private { - /// This trait being unreachable from outside the crate - /// prevents other implementations of the `ExitStatusExt` trait, - /// which allows potentially adding more trait methods in the future. - #[stable(feature = "none", since = "1.51.0")] - pub trait Sealed {} -} - /// Unix-specific extensions to the [`process::Command`] builder. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait CommandExt { +pub trait CommandExt: Sealed { /// Sets the child process's user ID. This translates to a /// `setuid` call in the child process. Failure in the `setuid` /// call will cause the spawn to fail. @@ -193,7 +189,7 @@ impl CommandExt for process::Command { /// This trait is sealed: it cannot be implemented outside the standard library. /// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait ExitStatusExt: private::Sealed { +pub trait ExitStatusExt: Sealed { /// Creates a new `ExitStatus` from the raw underlying `i32` return value of /// a process. #[stable(feature = "exit_status_from", since = "1.12.0")] @@ -228,9 +224,6 @@ pub trait ExitStatusExt: private::Sealed { fn into_raw(self) -> i32; } -#[stable(feature = "none", since = "1.51.0")] -impl private::Sealed for process::ExitStatus {} - #[stable(feature = "rust1", since = "1.0.0")] impl ExitStatusExt for process::ExitStatus { fn from_raw(raw: i32) -> Self { diff --git a/library/std/src/sys/windows/ext/ffi.rs b/library/std/src/sys/windows/ext/ffi.rs index 1df2a0df143b3..c89b9ff1efa6b 100644 --- a/library/std/src/sys/windows/ext/ffi.rs +++ b/library/std/src/sys/windows/ext/ffi.rs @@ -53,6 +53,7 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::ffi::{OsStr, OsString}; +use crate::sealed::Sealed; use crate::sys::os_str::Buf; use crate::sys_common::wtf8::Wtf8Buf; use crate::sys_common::{AsInner, FromInner}; @@ -61,8 +62,11 @@ use crate::sys_common::{AsInner, FromInner}; pub use crate::sys_common::wtf8::EncodeWide; /// Windows-specific extensions to [`OsString`]. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait OsStringExt { +pub trait OsStringExt: Sealed { /// Creates an `OsString` from a potentially ill-formed UTF-16 slice of /// 16-bit code units. /// @@ -92,8 +96,11 @@ impl OsStringExt for OsString { } /// Windows-specific extensions to [`OsStr`]. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait OsStrExt { +pub trait OsStrExt: Sealed { /// Re-encodes an `OsStr` as a wide character sequence, i.e., potentially /// ill-formed UTF-16. /// diff --git a/library/std/src/sys/windows/ext/process.rs b/library/std/src/sys/windows/ext/process.rs index 7a92381d6609b..3d680a7f2d94f 100644 --- a/library/std/src/sys/windows/ext/process.rs +++ b/library/std/src/sys/windows/ext/process.rs @@ -4,17 +4,10 @@ use crate::os::windows::io::{AsRawHandle, FromRawHandle, IntoRawHandle, RawHandle}; use crate::process; +use crate::sealed::Sealed; use crate::sys; use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner}; -mod private { - /// This trait being unreachable from outside the crate - /// prevents other implementations of the `ExitStatusExt` trait, - /// which allows potentially adding more trait methods in the future. - #[stable(feature = "none", since = "1.51.0")] - pub trait Sealed {} -} - #[stable(feature = "process_extensions", since = "1.2.0")] impl FromRawHandle for process::Stdio { unsafe fn from_raw_handle(handle: RawHandle) -> process::Stdio { @@ -85,7 +78,7 @@ impl IntoRawHandle for process::ChildStderr { /// This trait is sealed: it cannot be implemented outside the standard library. /// This is so that future additional methods are not breaking changes. #[stable(feature = "exit_status_from", since = "1.12.0")] -pub trait ExitStatusExt: private::Sealed { +pub trait ExitStatusExt: Sealed { /// Creates a new `ExitStatus` from the raw underlying `u32` return value of /// a process. #[stable(feature = "exit_status_from", since = "1.12.0")] @@ -99,12 +92,12 @@ impl ExitStatusExt for process::ExitStatus { } } -#[stable(feature = "none", since = "1.51.0")] -impl private::Sealed for process::ExitStatus {} - /// Windows-specific extensions to the [`process::Command`] builder. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "windows_process_extensions", since = "1.16.0")] -pub trait CommandExt { +pub trait CommandExt: Sealed { /// Sets the [process creation flags][1] to be passed to `CreateProcess`. /// /// These will always be ORed with `CREATE_UNICODE_ENVIRONMENT`. diff --git a/library/std/src/sys_common/os_str_bytes.rs b/library/std/src/sys_common/os_str_bytes.rs index 497e5fc7bdd16..302c519740717 100644 --- a/library/std/src/sys_common/os_str_bytes.rs +++ b/library/std/src/sys_common/os_str_bytes.rs @@ -6,6 +6,7 @@ use crate::ffi::{OsStr, OsString}; use crate::fmt; use crate::mem; use crate::rc::Rc; +use crate::sealed::Sealed; use crate::str; use crate::sync::Arc; use crate::sys_common::bytestring::debug_fmt_bytestring; @@ -232,8 +233,11 @@ impl Slice { } /// Platform-specific extensions to [`OsString`]. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait OsStringExt { +pub trait OsStringExt: Sealed { /// Creates an [`OsString`] from a byte vector. /// /// See the module documentation for an example. @@ -258,8 +262,11 @@ impl OsStringExt for OsString { } /// Platform-specific extensions to [`OsStr`]. +/// +/// This trait is sealed: it cannot be implemented outside the standard library. +/// This is so that future additional methods are not breaking changes. #[stable(feature = "rust1", since = "1.0.0")] -pub trait OsStrExt { +pub trait OsStrExt: Sealed { #[stable(feature = "rust1", since = "1.0.0")] /// Creates an [`OsStr`] from a byte slice. ///