Suggest enclosing format string with `""` under special cases
This commit adds suggestions on enclosing format string with `""` when it falls into the following 3 cases: `{}`, `{:?}`, `{:#?}` as mentioned in rust-lang/rust#155508.
Currently, this commit only recognizes the above 3 cases. I wonder if we should generalize this to more cases, for example, appying this suggestion to `Block`s with only 0 or 1 `Stmt`, such as `{:#x}`, `{:^10}`, `{abc}`.
macro_metavar_expr_concat: explain why idents are invalid
Recently I've been playing around with `macro_metavar_expr_concat` and in the process wasted more time than I'd have liked on debugging my dodgy idents. This should make that experience much nicer going forward.
* Suggest enclosing format string under special cases
This commit add suggestions about enclosing format string when it falls
into the following cases: `{}`, `{:?}`, `{:#?}`.
* Add HELP annotations in the UI test
Change keyword order for `impl` restrictions
Based on rust-lang/rust#155222, this PR reorders keywords in trait definitions to group restrictions with visibility. It changes the order from `pub(...) const unsafe auto impl(...) trait Foo {...}` to `pub(...) impl(...) const unsafe auto trait Foo {...}`.
Tracking issue for restrictions: rust-lang/rust#105077
r? @Urgau
cc @jhpratt
Make `span_suggestions` always verbose
`span_suggestions` is to provide mutually exclusive suggestions. When it was introduced, we made its behavior be that if a single suggestion is given to it, we present the suggestion inline, otherwise in patch format. Changing this to make all of its uses be verbose, as that is closer in intent of output.
`span_suggestions` is to provide mutually exclusive suggestions. When it was introduced, we made its behavior be that if a single suggestion is given to it, we present the suggestion inline, otherwise in patch format. Changing this to make all of its uses be verbose, as that is closer in intent of output.
Make the expansion of guard metavars begin guard non-terminals
While investigating something unrelated, I noticed a bug in the impl of unstable feature `macro_guard_matcher` (tracking issue: rust-lang/rust#153104). Namely, the following doesn't compile:
```rs
#![feature(macro_guard_matcher)]
macro_rules! a { ($guard:guard) => { b!($guard); }; }
macro_rules! b { ($guard:guard) => {}; }
a!(if true);
```
```
error: no rules expected `guard` metavariable
--> src/lib.rs:3:41
|
3 | macro_rules! a { ($guard:guard) => { b!($guard); }; }
| ^^^^^^ no rules expected this token in macro call
4 | macro_rules! b { ($guard:guard) => {}; }
| -------------- when calling this macro
5 | a!(if true);
| ----------- in this macro invocation
|
note: while trying to match meta-variable `$guard:guard`
--> src/lib.rs:4:19
|
4 | macro_rules! b { ($guard:guard) => {}; }
| ^^^^^^^^^^^^
= note: this error originates in the macro `a` (in Nightly builds, run with -Z macro-backtrace for more info)
```
---
While I'm still skeptical of `guard` fragment specifiers in general (although I can't quite pinpoint why), I figured I should fix this issue.
rustc_expand: improve diagnostics for non-repeatable metavars
There was an initally opened pr which solve this issue here https://github.com/rust-lang/rust/pull/152679. It got merged but, there was a perf regression. And this new pr is opened to address the problem. The first did the computation of binding and matched_rule and then passed them as owned value down to `diagnostics::emit_frag_parse_err(` but, now this pr address the issue by passing `lhs` and `rules` as borrowed value to from_tts and the move the logic to `diagnostics::emit_frag_parse_err(`.
Fix https://github.com/rust-lang/rust/issues/47452.
some `tests/ui/macros` cleanup
Move most tests that do not run any code from `//@ run-pass` to `//@ check-pass` and merge the (outdated) `die-macro-*` tests into one file.
Add macro matcher for `guard` fragment specifier
Tracking issue #153104
This PR implements a new `guard` macro matcher to match `if-let` guards (specifically [`MatchArmGuard`](https://github.com/rust-lang/reference/blob/50a1075e879be75aeec436252c84eef0fad489f4/src/expressions/match-expr.md#match-guards)). In the upcoming PR, we can use this new matcher in the `matches!` and `assert_matches!` macros to support their use with `if-let` guards. (see #152313)
The original `Expr` used to represent a guard has been wrapped in a new `Guard` type, allowing us to carry the span information of the leading `if` keyword. However, it might be even better to include the `if` keyword in the `Guard` type as well? I've left a FIXME comment in the code.
Allow passing `expr` metavariable as `cfg` predicate
This PR allows expanding `expr` metavariables inside the configuration predicates of `cfg` and `cfg_attr` invocations.
For example, the following code will now compile:
```rust
macro_rules! mac {
($e:expr) => {
#[cfg_attr($e, inline)]
#[cfg($e)]
fn func() {}
#[cfg(not($e))]
fn func() {
panic!()
}
}
}
mac!(any(unix, feature = "foo"));
```
There is currently no `macro_rules` fragment specifier that can represent all valid `cfg` predicates. `meta` comes closest, but excludes `true` and `false`. By fixing that, this change makes it easier to write declarative macros that parse `cfg` or `cfg_attr` invocations, for example https://github.com/rust-lang/rust/pull/146281/.
@rustbot label T-lang needs-fcp A-attributes A-cfg A-macros
Move some ui tests
> [!NOTE]
> I split the commits to make the review easier and to keep the git history easier to trace.
Renamed issue-xxx tests
`tests/ui/dyn-drop` -> `tests/ui/dyn-keyword`
`tests/ui/missing-trait-bounds` -> `tests/ui/trait-bound/missing-trait-bounds`
`tests/ui/recursion_limit` -> `tests/ui/recursion/recursion_limit`
`tests/ui/version` -> `tests/ui/compile-flags`
Reorganize `tests/ui/empty`
* Move dyn-drop to dyn-keyword
* Reorganize `tests/ui/empty` into specific dirs
remove tests/ui/empty/empty-linkname.rs duplicate of tests/ui/error-codes/E0454.rs
* Move `missing-trait-bounds` to `trait-bound/missing-trait-bounds`
* bless traits/missing-trait-bounds tests
* Move `recursion_limit` to `recursion/recursion_limit`
* Move `version` to `compile-flags`