Remove `TokenStreamBuilder`
`TokenStreamBuilder` is used to combine multiple token streams. It can be removed, leaving the code a little simpler and a little faster.
r? `@Aaron1011`
`TokenStreamBuilder` exists to concatenate multiple `TokenStream`s
together. This commit removes it, and moves the concatenation
functionality directly into `TokenStream`, via two new methods
`push_tree` and `push_stream`. This makes things both simpler and
faster.
`push_tree` is particularly important. `TokenStreamBuilder` only had a
single `push` method, which pushed a stream. But in practice most of the
time we push a single token tree rather than a stream, and `push_tree`
avoids the need to build a token stream with a single entry (which
requires two allocations, one for the `Lrc` and one for the `Vec`).
The main `push_tree` use arises from a change to one of the `ToInternal`
impls in `proc_macro_server.rs`. It now returns a `SmallVec` instead of
a `TokenStream`. This return value is then iterated over by
`concat_trees`, which does `push_tree` on each element. Furthermore, the
use of `SmallVec` avoids more allocations, because there is always only
one or two token trees.
Note: the removed `TokenStreamBuilder::push` method had some code to
deal with a quadratic blowup case from #57735. This commit removes the
code. I tried and failed to reproduce the blowup from that PR, before
and after this change. Various other changes have happened to
`TokenStreamBuilder` in the meantime, so I suspect the original problem
is no longer relevant, though I don't have proof of this. Generally
speaking, repeatedly extending a `Vec` without pre-determining its
capacity is *not* quadratic. It's also incredibly common, within rustc
and many other Rust programs, so if there were performance problems
there you'd think it would show up in other places, too.
`TokenTree::Punct` is handled outside the `match`. This commits moves it
inside the `match`, avoiding the need for the `return`s and making it
easier to read.
FIX - ambiguous Diagnostic link in docs
UPDATE - rename diagnostic_items to IntoDiagnostic and AddToDiagnostic
[Gardening] FIX - formatting via `x fmt`
FIX - rebase conflicts. NOTE: Confirm wheather or not we want to handle TargetDataLayoutErrorsWrapper this way
DELETE - unneeded allow attributes in Handler method
FIX - broken test
FIX - Rebase conflict
UPDATE - rename residual _SessionDiagnostic and fix LintDiag link
On later stages, the feature is already stable.
Result of running:
rg -l "feature.let_else" compiler/ src/librustdoc/ library/ | xargs sed -s -i "s#\\[feature.let_else#\\[cfg_attr\\(bootstrap, feature\\(let_else\\)#"
`To` is better than `Create` for indicating that this is a non-consuming
conversion, rather than creating something out of nothing.
And the addition of `Attr` is because the current names makes them sound
like they relate to `TokenStream`, but really they relate to
`AttrTokenStream`.
These two type names are long and have long matching prefixes. I find
them hard to read, especially in combinations like
`AttrAnnotatedTokenStream::new(vec![AttrAnnotatedTokenTree::Token(..)])`.
This commit renames them as `AttrToken{Stream,Tree}`.
Debuginfo line information for macro invocations are collapsed by
default - line information are replaced by the line of the outermost
expansion site. Using `-Zdebug-macros` disables this behaviour.
When the `collapse_debuginfo` feature is enabled, the default behaviour
is reversed so that debuginfo is not collapsed by default. In addition,
the `#[collapse_debuginfo]` attribute is available and can be applied to
macro definitions which will then have their line information collapsed.
Signed-off-by: David Wood <david.wood@huawei.com>
Fix a bunch of typo
This PR will fix some typos detected by [typos].
I only picked the ones I was sure were spelling errors to fix, mostly in
the comments.
[typos]: https://github.com/crate-ci/typos
proc_macro/bridge: send diagnostics over the bridge as a struct
This removes some RPC when creating and emitting diagnostics, and
simplifies the bridge slightly.
After this change, there are no remaining methods which take advantage
of the support for `&mut` references to objects in the store as
arguments, meaning that support for them could technically be removed if
we wanted. The only remaining uses of immutable references into the
store are `TokenStream` and `SourceFile`.
r? `@eddyb`
This PR will fix some typos detected by [typos].
I only picked the ones I was sure were spelling errors to fix, mostly in
the comments.
[typos]: https://github.com/crate-ci/typos
In some places we use `Vec<Attribute>` and some places we use
`ThinVec<Attribute>` (a.k.a. `AttrVec`). This results in various points
where we have to convert between `Vec` and `ThinVec`.
This commit changes the places that use `Vec<Attribute>` to use
`AttrVec`. A lot of this is mechanical and boring, but there are
some interesting parts:
- It adds a few new methods to `ThinVec`.
- It implements `MapInPlace` for `ThinVec`, and introduces a macro to
avoid the repetition of this trait for `Vec`, `SmallVec`, and
`ThinVec`.
Overall, it makes the code a little nicer, and has little effect on
performance. But it is a precursor to removing
`rustc_data_structures::thin_vec::ThinVec` and replacing it with
`thin_vec::ThinVec`, which is implemented more efficiently.
Migrations for rustc_expand transcribe.rs
This PR includes some migrations to the new diagnostics API for the `rustc_expand` module.
r? ```@davidtwco```
- Rename `ast::Lit::token` as `ast::Lit::token_lit`, because its type is
`token::Lit`, which is not a token. (This has been confusing me for a
long time.)
reasonable because we have an `ast::token::Lit` inside an `ast::Lit`.
- Rename `LitKind::{from,to}_lit_token` as
`LitKind::{from,to}_token_lit`, to match the above change and
`token::Lit`.
Implement `#[rustc_default_body_unstable]`
This PR implements a new stability attribute — `#[rustc_default_body_unstable]`.
`#[rustc_default_body_unstable]` controls the stability of default bodies in traits.
For example:
```rust
pub trait Trait {
#[rustc_default_body_unstable(feature = "feat", isssue = "none")]
fn item() {}
}
```
In order to implement `Trait` user needs to either
- implement `item` (even though it has a default implementation)
- enable `#![feature(feat)]`
This is useful in conjunction with [`#[rustc_must_implement_one_of]`](https://github.com/rust-lang/rust/pull/92164), we may want to relax requirements for a trait, for example allowing implementing either of `PartialEq::{eq, ne}`, but do so in a safe way — making implementation of only `PartialEq::ne` unstable.
r? `@Aaron1011`
cc `@nrc` (iirc you were interested in this wrt `read_buf`), `@danielhenrymantilla` (you were interested in the related `#[rustc_must_implement_one_of]`)
P.S. This is my first time working with stability attributes, so I'm not sure if I did everything right 😅
This removes some RPC when creating and emitting diagnostics, and
simplifies the bridge slightly.
After this change, there are no remaining methods which take advantage
of the support for `&mut` references to objects in the store as
arguments, meaning that support for them could technically be removed if
we wanted. The only remaining uses of immutable references into the
store are `TokenStream` and `SourceFile`.
