Improve diagnostics: update note and add help message
I moved the content from the note to a help message, as it seemed more appropriate there, and then added new information to the note(`Modules are usually placed outside of blocks, at the top level of the file`)!
resolve: rust-lang/rust#147314
mbe: Implement `unsafe` attribute rules
This implements `unsafe attr` rules for declarative `macro_rules!` attributes, as specified in [RFC 3697](https://github.com/rust-lang/rfcs/pull/3697).
An invocation of an attribute that uses an `unsafe attr` rule requires the `unsafe(attr(...))` syntax.
An invocation of an attribute that uses an ordinary `attr` rule must *not* use the `unsafe(attr(...))` syntax.
`unsafe` is only supported on an `attr` rule, not any other kind of `macro_rules!` rule.
Tracking issue for `macro_rules!` attributes: https://github.com/rust-lang/rust/issues/143547
`LegacyAttr` is only used for builtin attributes, and builtin attributes
have their safety checked by `check_attribute_safety`, so we don't need
to check `unsafety` here.
mbe: macro_check: Fix function comments referencing non-existent parameters
Several functions had comments referencing a non-existent `valid`
parameter. Remove those. The `guar` parameter that handles errors is
already documented.
In the process, remove another duplicate reference to an
already-documented parameter (`binders`).
mbe: Simplify check_redundant_vis_repetition
Eliminate a use of `map_or` in favor of a match.
Inline some variable definitions that don't add clarity, and that
prevent short-circuiting.
Reduce some uses of `LegacyBang`
- **Switch `dummy_bang` from `LegacyBang` to `Bang`**
- **mbe: Switch dummy extension used for errors from `LegacyBang` to `Bang`**
Several functions had comments referencing a non-existent `valid`
parameter. Remove those. The `guar` parameter that handles errors is
already documented.
In the process, remove another duplicate reference to an
already-documented parameter (`binders`).
mbe: Simplifications and refactoring
A few simplifications and refactors in advance of other work.
Macro metavariable expressions were using `Ident::as_str` and doing string
comparisons; I converted them to use symbols.
I factored out a function for transcribing a `ParseNtResult`, which will help
separate the evaluation and transcription of future macro metavariable
expressions.
support integer literals in `${concat()}`
Tracking issue: rust-lang/rust#124225
Adds support for using integer literals as arguments to `${concat()}` macro expressions.
Integer formatting such as `1_000` is preserved by this.
Strip frontmatter in fewer places
* Stop stripping frontmatter in `proc_macro::Literal::from_str` (RUST-146132)
* Stop stripping frontmatter in expr-ctxt (but not item-ctxt!) `include`s (RUST-145945)
* Stop stripping shebang (!) in `proc_macro::Literal::from_str`
* Not a breaking change because it did compare spans already to ensure there wasn't extra whitespace or comments (`Literal::from_str("#!\n0")` already yields `Err(_)` thankfully!)
* Stop stripping frontmatter+shebang inside some rustdoc code where it doesn't make any observable difference (see self review comments)
* (Stop stripping frontmatter+shebang inside internal test code)
Fixes https://github.com/rust-lang/rust/issues/145945.
Fixes https://github.com/rust-lang/rust/issues/146132.
r? fee1-dead
Derive `PartialEq` for `InvisibleOrigin`
For https://github.com/rust-lang/rust/pull/145354, we need `PartialEq` for `TokenStream` to "just work". However, due to the special comparison implementation that was used for `InvisibleOrigin`, this wasn't the case.
So I derived `PartialEq` for `InvisibleOrigin`, and used the previous special comparison logic only on the single place where it was actually required.
r? `````````@petrochenkov`````````
Add compiler error when trying to use concat metavar expr in repetitions
## Disclaimer
This is my first PR to rust, so if I missed/could improve something about this PR, please excuse and tell me!
## The improvement
The [metavar_expr_concat feature](https://github.com/rust-lang/rust/issues/124225) currently does not seem to support nested repetitions, and throws an ICE without much explanation if the relevant code path is hit.
This PR adds a draft compiler error that attempts to explain the issue. I am not 100% sure what all the ways of triggering this error are, so the message is currently pretty generic, please do correct me if there's something wrong with it or it could be improved.
Thank you for you time!
Fixesrust-lang/rust#140479.
This was done in #145740 and #145947. It is causing problems for people
using r-a on anything that uses the rustc-dev rustup package, e.g. Miri,
clippy.
This repository has lots of submodules and subtrees and various
different projects are carved out of pieces of it. It seems like
`[workspace.dependencies]` will just be more trouble than it's worth.
Refactor lint buffering to avoid requiring a giant enum
Lint buffering currently relies on a giant enum `BuiltinLintDiag` containing all the lints that might potentially get buffered. In addition to being an unwieldy enum in a central crate, this also makes `rustc_lint_defs` a build bottleneck: it depends on various types from various crates (with a steady pressure to add more), and many crates depend on it.
Having all of these variants in a separate crate also prevents detecting when a variant becomes unused, which we can do with a dedicated type defined and used in the same crate.
Refactor this to use a dyn trait, to allow using `LintDiagnostic` types directly.
Because the existing `BuiltinLintDiag` requires some additional types in order to decorate some variants, which are only available later in `rustc_lint`, use an enum `DecorateDiagCompat` to handle both the `dyn LintDiagnostic` case and the `BuiltinLintDiag` case.
---
With the infrastructure in place, use it to migrate three of the enum variants to use `LintDiagnostic` directly, as a proof of concept and to demonstrate that the net result is a reduction in code size and a removal of a boilerplate-heavy layer of indirection.
Also remove an unused `BuiltinLintDiag` variant.
Rewrite the new attribute argument parser
Fixes https://github.com/rust-lang/rust/issues/143940
This rewrites the parser, should improve performance and maintainability.
This can be reviewed commit by commit
Lint buffering currently relies on a giant enum `BuiltinLintDiag`
containing all the lints that might potentially get buffered. In
addition to being an unwieldy enum in a central crate, this also makes
`rustc_lint_defs` a build bottleneck: it depends on various types from
various crates (with a steady pressure to add more), and many crates
depend on it.
Having all of these variants in a separate crate also prevents detecting
when a variant becomes unused, which we can do with a dedicated type
defined and used in the same crate.
Refactor this to use a dyn trait, to allow using `LintDiagnostic` types
directly.
This requires boxing, but all of this is already on the slow path
(emitting an error).
Because the existing `BuiltinLintDiag` requires some additional types in
order to decorate some variants, which are only available later in
`rustc_lint`, use an enum `DecorateDiagCompat` to handle both the `dyn
LintDiagnostic` case and the `BuiltinLintDiag` case.
