We have to deal with dummy spans anyway
Remove def-site span from expander interfaces.
It's not used by the expansion infra, only by specific expanders, which can keep it themselves if they want it.
To implement pipelining, Cargo needs to know when metadata generation is
finished. This commit adds code to do that. Unfortunately, metadata file
writing currently occurs very late during compilation, so pipelining
won't produce a speed-up. Moving metadata file writing earlier will be a
follow-up.
The change involves splitting the existing `Emitter::emit` method in
two: `Emitter::emit_diagnostic` and `Emitter::emit_directive`.
The JSON directives look like this:
```
{"directive":"metadata file written: liba.rmeta"}
```
The functionality is behind the `-Z emit-directives` option, and also
requires `--error-format=json`.
Rename rustc_errors dependency in rust 2018 crates
I think this is a better solution than `use rustc_errors as errors` in `lib.rs` and `use crate::errors` in modules.
Related: rust-lang/cargo#5653
cc #58099
r? @Centril
Add approximate suggestions for rustfix
This adds `span_approximate_suggestion()` that lets you emit a
suggestion marked as "non-machine applicable" in the JSON output. UI
users see no difference. This is for when rustc and clippy wish to
emit suggestions which will make sense to the reader (e.g. they may
have placeholders like `<type>`) but are not source-applicable, so that
rustfix/etc can ignore these.
fixes#39254
This adds `span_approximate_suggestion()` that lets you emit a
suggestion marked as "approximate" in the JSON output. UI
users see no difference. This is for when rustc and clippy wish to
emit suggestions which will make sense to the reader (e.g. they may
have placeholders like `<type>`) but are not source-applicable, so that
rustfix/etc can ignore these.
fixes#39254
Refactor internal suggestion API
~~The only functional change is that whitespace, which is suggested to be added, also gets `^^^^` under it. An example is shown in the tests (the only test that changed).~~
Continuation of #41876
r? @nagisa
the changes are probably best viewed [without whitespace](https://github.com/rust-lang/rust/pull/45741/files?w=1)