Do not emit note suggesting to implement operation trait to foreign type
When a binary operation isn't valid, you will get a lint proposing to add a trait implementation to make the operation possible. However, this cannot be done for foreign types, such as types from `core` or `std`.
For example:
```
= note: an implementation of `std::ops::Add` might be missing for `std::option::Option<i8>`
```
As mentioned in https://github.com/rust-lang/rust/issues/60497#issuecomment-562665539:
> The note suggesting implementing Add<i8> should only be emitted if Option<i8> were local to the current crate, which it isn't, so in this case it shouldn't be emitted.
(I will use the CI to check tests for me, or my computer will just burn... and running IDEs is not possible on a pile of ashes)
r? @estebank
parser: Simplify treatment of macro variables in `Parser::bump`
Follow-up to https://github.com/rust-lang/rust/pull/69006.
Token normalization for `$ident` and `$lifetime` is merged directly into `bump`.
Special "unknown macro variable" diagnostic for unexpected `$`s is removed as preventing legal code from compiling (as a result `bump` also doesn't call itself recursively anymore and can't make `prev_token` inconsistent).
r? @Centril
parse: fuse associated and extern items up to defaultness
Language changes:
- The grammar of extern `type` aliases is unified with associated ones, and becomes:
```rust
TypeItem = "type" ident generics {":" bounds}? where_clause {"=" type}? ";" ;
```
Semantic restrictions (`ast_validation`) are added to forbid any parameters in `generics`, any bounds in `bounds`, and any predicates in `where_clause`, as well as the presence of a type expression (`= u8`).
(Work still remains to fuse this with free `type` aliases, but this can be done later.)
- The grammar of constants and static items (free, associated, and extern) now permits the absence of an expression, and becomes:
```rust
GlobalItem = {"const" {ident | "_"} | "static" "mut"? ident} {"=" expr}? ";" ;
```
- A semantic restriction is added to enforce the presence of the expression (the body).
- A semantic restriction is added to reject `const _` in associated contexts.
Together, these changes allow us to fuse the grammar of associated items and extern items up to `default`ness which is the main goal of the PR.
-----------------------
We are now very close to fully fusing the entirely of item parsing and their ASTs. To progress further, we must make a decision: should we parse e.g. `default use foo::bar;` and whatnot? Accepting that is likely easiest from a parsing perspective, as it does not require using look-ahead, but it is perhaps not too onerous to only accept it for `fn`s (and all their various qualifiers), `const`s, `static`s, and `type`s.
r? @petrochenkov
recursion_limit parsing handles overflows
This PR adds overflow handling to `#![recursion_limit]` attribute parsing. If parsing the given value results in an `IntErrorKind::Overflow`, then the recursion_limit is set to `usize::max_value()`.
closes#67265
Token normalization is merged directly into `bump`.
Special "unknown macro variable" diagnostic for unexpected `$`s is removed as preventing legal code from compiling.
This prevents accidental dereferences and so forth of the Void type, as well as
cleaning up the error message to reference Opaque rather than the more
complicated PhantomData type.
This adds parsing for expressions like 'x as Ty[0]' which will
immediately error out, but still give the rest of the parser a valid
parse tree to continue.
Fixes#68690
When we generate the proc macro harness, we now explicitly recorder the
order in which we generate entries. We then use this ordering data to
deserialize the correct proc-macro-data from the crate metadata.
Suggest a comma if a struct initializer field fails to parse
Currently, we emit a "try adding a comma" suggestion if a comma is
missing in a struct definition. However, we emit no such suggestion if a
comma is missing in a struct initializer.
This commit adds a "try adding a comma" suggestion when we don't find a
comma during the parsing of a struct initializer field.
The change to `src/test/ui/parser/removed-syntax-with-1.stderr` isn't
great, but I don't see a good way of avoiding it.
Currently, we emit a "try adding a comma" suggestion if a comma is
missing in a struct definition. However, we emit no such suggestion if a
comma is missing in a struct initializer.
This commit adds a "try adding a comma" suggestion when we don't find a
comma during the parsing of a struct initializer field.
The change to `src/test/ui/parser/removed-syntax-with-1.stderr` isn't
great, but I don't see a good way of avoiding it.
Infer regions for opaque types in borrowck
This is a step towards the goal of typeck not doing region inference.
The commits up to `Arena allocate the result of mir_borrowck` are various bug fixes and prerequisites.
The remaining commits move opaque type inference to borrow checking.
r? @nikomatsakis
