This upcast coercion currently preserves the vtable for the object, but
eventually it can be used to create a derived vtable. The upcast
coercion is not introduced into method dispatch; see comment on #18737
for information about why. Fixes#18737.
This removes the error case of the compression functions, the only errors that
can occur are incorrect parameters or an out-of-memory condition, both of which
are handled with panics in Rust.
Also introduces an extensible `Error` type instead of returning an `Option`.
The type implements a destructor so you can't destructure it.
This removes the error case of the compression functions, the only errors that
can occur are incorrect parameters or an out-of-memory condition, both of which
are handled with panics in Rust.
Also introduces an extensible `Error` type instead of returning an `Option`.
This commit deprecates the `count`, `range` and `range_step` functions
in `iter`, in favor of range notation. To recover all existing
functionality, a new `step_by` adapter is provided directly on `ops::Range`
and `ops::RangeFrom`.
[breaking-change]
r? @alexcrichton
It wasn't clear to me that early_error was correct here, but it seems to
work. This code is reachable from `rustdoc`, which is problematic, because
early_error panics. rustc handles the panics gracefully (without ICEing or
crashing), but rustdoc does not. It's not the first such rustdoc problem,
though:
$ rustdoc hello.rs --extern std=bad-std
error: extern location for std does not exist: bad-std
hello.rs:1:1: 1:1 error: can't find crate for `std`
hello.rs:1
^
error: aborting due to 2 previous errors
thread '<unnamed>' panicked at 'Box<Any>', /home/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/libsyntax/diagnostic.rs:151
thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: "rustc failed"', /home/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/libcore/result.rs:744
thread '<main>' panicked at 'child thread None panicked', /home/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/libstd/thread.rs:661
This commit deprecates the `count`, `range` and `range_step` functions
in `iter`, in favor of range notation. To recover all existing
functionality, a new `step_by` adapter is provided directly on `ops::Range`
and `ops::RangeFrom`.
[breaking-change]
The new `std::io` module has had some time to bake now, and this commit
stabilizes its functionality. There are still portions of the module which
remain unstable, and below contains a summart of the actions taken.
This commit also deprecates the entire contents of the `old_io` module in a
blanket fashion. All APIs should now have a reasonable replacement in the
new I/O modules.
Stable APIs:
* `std::io` (the name)
* `std::io::prelude` (the name)
* `Read`
* `Read::read`
* `Read::{read_to_end, read_to_string}` after being modified to return a `usize`
for the number of bytes read.
* `ReadExt`
* `Write`
* `Write::write`
* `Write::{write_all, write_fmt}`
* `WriteExt`
* `BufRead`
* `BufRead::{fill_buf, consume}`
* `BufRead::{read_line, read_until}` after being modified to return a `usize`
for the number of bytes read.
* `BufReadExt`
* `BufReader`
* `BufReader::{new, with_capacity}`
* `BufReader::{get_ref, get_mut, into_inner}`
* `{Read,BufRead} for BufReader`
* `BufWriter`
* `BufWriter::{new, with_capacity}`
* `BufWriter::{get_ref, get_mut, into_inner}`
* `Write for BufWriter`
* `IntoInnerError`
* `IntoInnerError::{error, into_inner}`
* `{Error,Display} for IntoInnerError`
* `LineWriter`
* `LineWriter::{new, with_capacity}` - `with_capacity` was added
* `LineWriter::{get_ref, get_mut, into_inner}` - `get_mut` was added)
* `Write for LineWriter`
* `BufStream`
* `BufStream::{new, with_capacities}`
* `BufStream::{get_ref, get_mut, into_inner}`
* `{BufRead,Read,Write} for BufStream`
* `stdin`
* `Stdin`
* `Stdin::lock`
* `Stdin::read_line` - added method
* `StdinLock`
* `Read for Stdin`
* `{Read,BufRead} for StdinLock`
* `stdout`
* `Stdout`
* `Stdout::lock`
* `StdoutLock`
* `Write for Stdout`
* `Write for StdoutLock`
* `stderr`
* `Stderr`
* `Stderr::lock`
* `StderrLock`
* `Write for Stderr`
* `Write for StderrLock`
* `io::Result`
* `io::Error`
* `io::Error::last_os_error`
* `{Display, Error} for Error`
Unstable APIs:
(reasons can be found in the commit itself)
* `Write::flush`
* `Seek`
* `ErrorKind`
* `Error::new`
* `Error::from_os_error`
* `Error::kind`
Deprecated APIs
* `Error::description` - available via the `Error` trait
* `Error::detail` - available via the `Display` implementation
* `thread::Builder::{stdout, stderr}`
Changes in functionality:
* `old_io::stdio::set_stderr` is now a noop as the infrastructure for printing
backtraces has migrated to `std::io`.
[breaking-change]
This implements a wish suggested in #17410, detecting enum variants that are never constructed, even in the presence of `#[derive(Clone)]`. The implementation is general and not specific to `#[derive(Clone)]`.
r? @jakub-
This commit stabilizes essentially all of the new `std::path` API. The
API itself is changed in a couple of ways (which brings it in closer
alignment with the RFC):
* `.` components are now normalized away, unless they appear at the
start of a path. This in turn effects the semantics of e.g. asking for
the file name of `foo/` or `foo/.`, both of which yield `Some("foo")`
now. This semantics is what the original RFC specified, and is also
desirable given early experience rolling out the new API.
* The `parent` method is now `without_file` and succeeds if, and only
if, `file_name` is `Some(_)`. That means, in particular, that it fails
for a path like `foo/../`. This change affects `pop` as well.
In addition, the `old_path` module is now deprecated.
[breaking-change]
r? @alexcrichton
This commit stabilizes essentially all of the new `std::path` API. The
API itself is changed in a couple of ways (which brings it in closer
alignment with the RFC):
* `.` components are now normalized away, unless they appear at the
start of a path. This in turn effects the semantics of e.g. asking for
the file name of `foo/` or `foo/.`, both of which yield `Some("foo")`
now. This semantics is what the original RFC specified, and is also
desirable given early experience rolling out the new API.
* The `parent` function now succeeds if, and only if, the path has at
least one non-root/prefix component. This change affects `pop` as
well.
* The `Prefix` component now involves a separate `PrefixComponent`
struct, to better allow for keeping both parsed and unparsed prefix data.
In addition, the `old_path` module is now deprecated.
Closes#23264
[breaking-change]
The end result is that common fields (id, name, attributes, etc.) are stored in now-structures `ImplItem` and `TraitItem`.
The signature of a method is no longer duplicated between methods with a body (default/impl) and those without, they now share `MethodSig`.
This is also a [breaking-change] because of minor bugfixes and changes to syntax extensions:
* `pub fn` methods in a trait no longer parse - remove the `pub`, it has no meaning anymore
* `MacResult::make_methods` is now `make_impl_items` and the return type has changed accordingly
* `quote_method` is gone, because `P<ast::Method>` doesn't exist and it couldn't represent a full method anyways - could be replaced by `quote_impl_item`/`quote_trait_item` in the future, but I do hope we realize how silly that combinatorial macro expansion is and settle on a single `quote` macro + some type hints - or just no types at all (only token-trees)
r? @nikomatsakis This is necessary (hopefully also sufficient) for associated constants.
now have a simple set of trait def-ids. During coherence, we use a
separate table to track the default impls for any given trait so that we
can report a nice error. This fixes various bugs in the metadata
encoding that led to `ty::trait_has_default_impl` yielding the wrong
values in the cross-crate case. (In particular, default impl def-ids
were not included in the list of all impl def-ids; I debated fixing just
that, but this approach seemed cleaner overall, since we usually treat
the "defaulted" bit on traits as being a property of the trait, and now
iterating over a list of impls doesn't intermingle default impls with
normal impls.)
Unstable items used in a macro expansion will now always trigger
stability warnings, *unless* the unstable items are directly inside a
macro marked with `#[allow_internal_unstable]`. IOW, the compiler warns
unless the span of the unstable item is a subspan of the definition of a
macro marked with that attribute.
E.g.
#[allow_internal_unstable]
macro_rules! foo {
($e: expr) => {{
$e;
unstable(); // no warning
only_called_by_foo!();
}}
}
macro_rules! only_called_by_foo {
() => { unstable() } // warning
}
foo!(unstable()) // warning
The unstable inside `foo` is fine, due to the attribute. But the
`unstable` inside `only_called_by_foo` is not, since that macro doesn't
have the attribute, and the `unstable` passed into `foo` is also not
fine since it isn't contained in the macro itself (that is, even though
it is only used directly in the macro).
In the process this makes the stability tracking much more precise,
e.g. previously `println!("{}", unstable())` got no warning, but now it
does. As such, this is a bug fix that may cause [breaking-change]s.
The attribute is definitely feature gated, since it explicitly allows
side-stepping the feature gating system.
---
This updates `thread_local!` macro to use the attribute, since it uses
unstable features internally (initialising a struct with unstable
fields).
This commit performs a stabilization pass over the `std::fs` module now that
it's had some time to bake. The change was largely just adding `#[stable]` tags,
but there are a few APIs that remain `#[unstable]`.
The following apis are now marked `#[stable]`:
* `std::fs` (the name)
* `File`
* `Metadata`
* `ReadDir`
* `DirEntry`
* `OpenOptions`
* `Permissions`
* `File::{open, create}`
* `File::{sync_all, sync_data}`
* `File::set_len`
* `File::metadata`
* Trait implementations for `File` and `&File`
* `OpenOptions::new`
* `OpenOptions::{read, write, append, truncate, create}`
* `OpenOptions::open` - this function was modified, however, to not attempt to
reject cross-platform openings of directories. This means that some platforms
will succeed in opening a directory and others will fail.
* `Metadata::{is_dir, is_file, len, permissions}`
* `Permissions::{readonly, set_readonly}`
* `Iterator for ReadDir`
* `DirEntry::path`
* `remove_file` - like with `OpenOptions::open`, the extra windows code to
remove a readonly file has been removed. This means that removing a readonly
file will succeed on some platforms but fail on others.
* `metadata`
* `rename`
* `copy`
* `hard_link`
* `soft_link`
* `read_link`
* `create_dir`
* `create_dir_all`
* `remove_dir`
* `remove_dir_all`
* `read_dir`
The following apis remain `#[unstable]`.
* `WalkDir` and `walk` - there are many methods by which a directory walk can be
constructed, and it's unclear whether the current semantics are the right
ones. For example symlinks are not handled super well currently. This is now
behind a new `fs_walk` feature.
* `File::path` - this is an extra abstraction which the standard library
provides on top of what the system offers and it's unclear whether we should
be doing so. This is now behind a new `file_path` feature.
* `Metadata::{accessed, modified}` - we do not currently have a good
abstraction for a moment in time which is what these APIs should likely be
returning, so these remain `#[unstable]` for now. These are now behind a new
`fs_time` feature
* `set_file_times` - like with `Metadata::accessed`, we do not currently have
the appropriate abstraction for the arguments here so this API remains
unstable behind the `fs_time` feature gate.
* `PathExt` - the precise set of methods on this trait may change over time and
some methods may be removed. This API remains unstable behind the `path_ext`
feature gate.
* `set_permissions` - we may wish to expose a more granular ability to set the
permissions on a file instead of just a blanket \"set all permissions\" method.
This function remains behind the `fs` feature.
The following apis are now `#[deprecated]`
* The `TempDir` type is now entirely deprecated and is [located on
crates.io][tempdir] as the `tempdir` crate with [its source][github] at
rust-lang/tempdir.
[tempdir]: https://crates.io/crates/tempdir
[github]: https://github.com/rust-lang/tempdir
The stability of some of these APIs has been questioned over the past few weeks
in using these APIs, and it is intentional that the majority of APIs here are
marked `#[stable]`. The `std::fs` module has a lot of room to grow and the
material is [being tracked in a RFC issue][rfc-issue].
[rfc-issue]: rust-lang/rfcs#939
Closes#22879
[breaking-change]
This commit is an implementation of [RFC 563][rfc] which adds a new
`cfg(debug_assertions)` directive which is specially recognized and calculated
by the compiler. The flag is turned off at any optimization level greater than 1
and may also be explicitly controlled through the `-C debug-assertions`
flag.
[rfc]: https://github.com/rust-lang/rfcs/pull/563
The `debug_assert!` and `debug_assert_eq!` macros now respect this instead of
the `ndebug` variable and `ndebug` no longer holds any meaning to the standard
library.
Code which was previously relying on `not(ndebug)` to gate expensive code should
be updated to rely on `debug_assertions` instead.
Closes#22492
[breaking-change]
Unstable items used in a macro expansion will now always trigger
stability warnings, *unless* the unstable items are directly inside a
macro marked with `#[allow_internal_unstable]`. IOW, the compiler warns
unless the span of the unstable item is a subspan of the definition of a
macro marked with that attribute.
E.g.
#[allow_internal_unstable]
macro_rules! foo {
($e: expr) => {{
$e;
unstable(); // no warning
only_called_by_foo!();
}}
}
macro_rules! only_called_by_foo {
() => { unstable() } // warning
}
foo!(unstable()) // warning
The unstable inside `foo` is fine, due to the attribute. But the
`unstable` inside `only_called_by_foo` is not, since that macro doesn't
have the attribute, and the `unstable` passed into `foo` is also not
fine since it isn't contained in the macro itself (that is, even though
it is only used directly in the macro).
In the process this makes the stability tracking much more precise,
e.g. previously `println!(\"{}\", unstable())` got no warning, but now it
does. As such, this is a bug fix that may cause [breaking-change]s.
The attribute is definitely feature gated, since it explicitly allows
side-stepping the feature gating system.
---
This updates `thread_local!` macro to use the attribute, since it uses
unstable features internally (initialising a struct with unstable
fields).
This commit performs a stabilization pass over the `std::fs` module now that
it's had some time to bake. The change was largely just adding `#[stable]` tags,
but there are a few APIs that remain `#[unstable]`.
The following apis are now marked `#[stable]`:
* `std::fs` (the name)
* `File`
* `Metadata`
* `ReadDir`
* `DirEntry`
* `OpenOptions`
* `Permissions`
* `File::{open, create}`
* `File::{sync_all, sync_data}`
* `File::set_len`
* `File::metadata`
* Trait implementations for `File` and `&File`
* `OpenOptions::new`
* `OpenOptions::{read, write, append, truncate, create}`
* `OpenOptions::open` - this function was modified, however, to not attempt to
reject cross-platform openings of directories. This means that some platforms
will succeed in opening a directory and others will fail.
* `Metadata::{is_dir, is_file, len, permissions}`
* `Permissions::{readonly, set_readonly}`
* `Iterator for ReadDir`
* `DirEntry::path`
* `remove_file` - like with `OpenOptions::open`, the extra windows code to
remove a readonly file has been removed. This means that removing a readonly
file will succeed on some platforms but fail on others.
* `metadata`
* `rename`
* `copy`
* `hard_link`
* `soft_link`
* `read_link`
* `create_dir`
* `create_dir_all`
* `remove_dir`
* `remove_dir_all`
* `read_dir`
The following apis remain `#[unstable]`.
* `WalkDir` and `walk` - there are many methods by which a directory walk can be
constructed, and it's unclear whether the current semantics are the right
ones. For example symlinks are not handled super well currently. This is now
behind a new `fs_walk` feature.
* `File::path` - this is an extra abstraction which the standard library
provides on top of what the system offers and it's unclear whether we should
be doing so. This is now behind a new `file_path` feature.
* `Metadata::{accessed, modified}` - we do not currently have a good
abstraction for a moment in time which is what these APIs should likely be
returning, so these remain `#[unstable]` for now. These are now behind a new
`fs_time` feature
* `set_file_times` - like with `Metadata::accessed`, we do not currently have
the appropriate abstraction for the arguments here so this API remains
unstable behind the `fs_time` feature gate.
* `PathExt` - the precise set of methods on this trait may change over time and
some methods may be removed. This API remains unstable behind the `path_ext`
feature gate.
* `set_permissions` - we may wish to expose a more granular ability to set the
permissions on a file instead of just a blanket "set all permissions" method.
This function remains behind the `fs` feature.
The following apis are now `#[deprecated]`
* The `TempDir` type is now entirely deprecated and is [located on
crates.io][tempdir] as the `tempdir` crate with [its source][github] at
rust-lang/tempdir.
[tempdir]: https://crates.io/crates/tempdir
[github]: https://github.com/rust-lang/tempdir
The stability of some of these APIs has been questioned over the past few weeks
in using these APIs, and it is intentional that the majority of APIs here are
marked `#[stable]`. The `std::fs` module has a lot of room to grow and the
material is [being tracked in a RFC issue][rfc-issue].
[rfc-issue]: https://github.com/rust-lang/rfcs/issues/939
[breaking-change]
The two main sub-modules, `c_str` and `os_str`, have now had some time to bake
in the standard library. This commits performs a sweep over the modules adding
various stability tags.
The following APIs are now marked `#[stable]`
* `OsString`
* `OsStr`
* `OsString::from_string`
* `OsString::from_str`
* `OsString::new`
* `OsString::into_string`
* `OsString::push` (renamed from `push_os_str`, added an `AsOsStr` bound)
* various trait implementations for `OsString`
* `OsStr::from_str`
* `OsStr::to_str`
* `OsStr::to_string_lossy`
* `OsStr::to_os_string`
* various trait implementations for `OsStr`
* `CString`
* `CStr`
* `NulError`
* `CString::new` - this API's implementation may change as a result of
rust-lang/rfcs#912 but the usage of `CString::new(thing)` looks like it is
unlikely to change. Additionally, the `IntoBytes` bound is also likely to
change but the set of implementors for the trait will not change (despite the
trait perhaps being renamed).
* `CString::from_vec_unchecked`
* `CString::as_bytes`
* `CString::as_bytes_with_nul`
* `NulError::nul_position`
* `NulError::into_vec`
* `CStr::from_ptr`
* `CStr::as_ptr`
* `CStr::to_bytes`
* `CStr::to_bytes_with_nul`
* various trait implementations for `CStr`
The following APIs remain `#[unstable]`
* `OsStr*Ext` traits remain unstable as the organization of `os::platform` is
uncertain still and the traits may change location.
* `AsOsStr` remains unstable as generic conversion traits are likely to be
rethought soon.
The following APIs were deprecated
* `OsString::push_os_str` is now called `push` and takes `T: AsOsStr` instead (a
superset of the previous functionality).