Joshua Nelson e3031fe22a Allow registering tool lints with register_tool
Previously, there was no way to add a custom tool prefix, even if the tool
itself had registered a lint:

 ```
 #![feature(register_tool)]
 #![register_tool(xyz)]
 #![warn(xyz::my_lint)]
 ```

```
$ rustc unknown-lint.rs  --crate-type lib
error[E0710]: an unknown tool name found in scoped lint: `xyz::my_lint`
 --> unknown-lint.rs:3:9
  |
3 | #![warn(xyz::my_lint)]
  |         ^^^
```

This allows opting-in to lints from other tools using `register_tool`.
2021-03-16 17:33:03 -04:00
..
2021-02-14 18:03:11 +03:00

The rustc_ast crate contains those things concerned purely with syntax that is, the AST ("abstract syntax tree"), parser, pretty-printer, lexer, macro expander, and utilities for traversing ASTs.

For more information about how these things work in rustc, see the rustc dev guide: