This enforces that eof() must be called to get the String out, and
generally is better from an API perspective. No users of pretty printing
pre-allocate the buffer.
This function took too many arguments and are simple on the inside;
inlining them makes complexity go down.
hir::print's copy is unfortunately used from librustc_driver so inlining
it is not as straightforward.
rustdoc: set cfg(doctest) when collecting doctests
Note: This PR builds on top of https://github.com/rust-lang/rust/pull/61199; only the last commit is specific to this PR.
As discussed in https://github.com/rust-lang/rust/pull/61199, we want the ability to isolate items to only when rustdoc is collecting doctests, but we can't use `cfg(test)` because of libcore's `#![cfg(not(test))]`. This PR proposes a new cfg flag, `cfg(doctest)`, specific to this situation, rather than reusing an existing flag. I've isolated it behind a feature gate so that we can contain the effects to nightly only. (A stable workaround that can be used in lieu of `#[cfg(doctest)]` is `#[cfg(rustdoc)] #[doc(hidden)]`, at least once https://github.com/rust-lang/rust/pull/61351 lands.)
Tracking issue: https://github.com/rust-lang/rust/issues/62210
Now that procedural macros no longer link transitively to libsyntax,
this shouldn't be needed any more! This commit is an experiment in
removing all dynamic libraries from rustc except for librustc_driver
itself. Let's see how far we can get with that!
Remove support for 1-token lookahead from the lexer
`StringReader` maintained `peek_token` and `peek_span_src_raw` for look ahead.
`peek_token` was used only by rustdoc syntax coloring. After moving peeking logic into highlighter, I was able to remove `peek_token` from the lexer. I tried to use `iter::Peekable`, but that wasn't as pretty as I hoped, due to buffered fatal errors. So I went with hand-rolled peeking.
After that I've noticed that the only peeking behavior left was for raw tokens to test tt jointness. I've rewritten it in terms of trivia tokens, and not just spans.
After that it became possible to simplify the awkward constructor of the lexer, which could return `Err` if the first peeked token contained error.
Implement another internal lints
cc #49509
This adds ~~two~~ one internal lint~~s~~:
1. LINT_PASS_IMPL_WITHOUT_MACRO: Make sure, that the `{declare,impl}_lint_pass` macro is used to implement lint passes. cc #59669
2. ~~USAGE_OF_TYCTXT_AND_SPAN_ARGS: item 2 on the list in #49509~~
~~With 2. I wasn't sure, if this lint should be applied everywhere. That means a careful review of 0955835 would be great. Also 73fb9b4 allows this lint on some functions. Should I also apply this lint there?~~
TODO (not directly relevant for review):
- [ ] https://github.com/rust-lang/rust/pull/59316#discussion_r280186517 (not sure yet, if this works or how to query for `rustc_private`, since it's not in [`Features`](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/feature_gate/struct.Features.html) 🤔 cc @eddyb)
- [x] https://github.com/rust-lang/rust/pull/61735#discussion_r292389870
- [x] Check explicitly for the `{declare,impl}_lint_pass!` macros
r? @oli-obk
