This commit adds a reproduction of the error reported in servo which
demonstrates the current, incorrect behaviour.
Co-authored-by: Rémy Rakić <remy.rakic@gmail.com>
The idea here is to make a reusable library out of the existing
rust-lexer, by separating out pure lexing and rustc-specific concerns,
like spans, error reporting an interning.
So, rustc_lexer operates directly on `&str`, produces simple tokens
which are a pair of type-tag and a bit of original text, and does not
report errors, instead storing them as flags on the token.
Specific error for positional args after named args in `format!()`
When writing positional arguments after named arguments in the
`format!()` and `println!()` macros, provide a targeted diagnostic.
Follow up to https://github.com/rust-lang/rust/pull/57522/files#r247278885
Add meta-variable checks in macro definitions
This is an implementation of #61053. It is not sound (some errors are not reported) and not complete (reports may not be actual errors). This is due to the possibility to define macros in macros in indirect ways. See module documentation of `macro_check` for more details.
What remains to be done:
- [x] Migrate from an error to an allow-by-default lint.
- [x] Add more comments in particular for the handling of nested macros.
- [x] Add more tests if needed.
- [x] Try to avoid cloning too much (one idea is to use lists on the stack).
- [ ] Run crater with deny-by-default lint (measure rate of false positives).
- [ ] Remove extra commit for deny-by-default lint
- [x] Create a PR to remove the old `question_mark_macro_sep` lint #62160
libsyntax: Rename `Mark` into `ExpnId`
"`Mark`" is an ID that identifies both a macro invocation (`foo!()`), and expansion process, and expansion result of that macro invocation.
The problem is that it's pretty hard to infer that from its name.
This PR renames it into `ExpnId` reflecting its meaning in most contexts.
(The contexts where it's meaning is closer to "macro invocation ID" are rarer.)
I've kept "mark" in the names of functions that add or remove marks to/from syntactic contexts, those marks are not just expansion IDs, but something more complex.
This is needed for having complete error messages where reporting macro variable
errors. Here is what they would look like:
error: meta-variable repeats with different kleene operator
--> $DIR/issue-61053-different-kleene.rs:3:57
|
LL | ( $( $i:ident = $($j:ident),+ );* ) => { $( $( $i = $j; )* )* };
| - expected repetition ^^ - conflicting repetition
