Started rebasing @sgrif's PR #33135 off of current master. (Well, actually merging it into a new branch based off current master.)
The following files still need to be fixed or at least reviewed:
- `src/libsyntax/ext/tt/macro_parser.rs`: calls `Parser::parse_lifetime`, which doesn't exist anymore
- `src/libsyntax/parse/parser.rs`: @sgrif added an error message to `Parser::parse_lifetime`. Code has since been refactored, so I just took it out for now.
- `src/libsyntax/ext/tt/transcribe.rs`: This code has been refactored bigtime. Not sure whether @sgrif's changes here are still necessary. Took it out for this commit.
Do not expand a derive invocation when derive is not allowed
Closes#46655.
The first commit is what actually closes#46655. The second one is just a refactoring I have done while waiting on a test.
Implements RFC 1937: `?` in `main`
This is the first part of the RFC 1937 that supports new
`Termination` trait in the rust `main` function.
Thanks @nikomatsakis, @arielb1 and all other people in the gitter channel for all your help!
The support for doctest and `#[test]` is still missing, bu as @nikomatsakis said, smaller pull requests are better :)
Make the output of the column! macro 1 based
Fixes #46868.
I didn't add any regression tests as the change already had to change tests inside the codebase.
r? @dtolnay
1. Change the return type of `expand_invoc()` and its subroutines to
`Option<Expansion>` from `Expansion`.
2. Return `None` when expanding a derive invocation if the item cannot
have derive on it (in `expand_derive_invoc()`).
Do not emit type errors on recovered blocks
When a parse error occurs on a block, the parser will recover and create
a block with the statements collected until that point. Now a flag
stating that a recovery has been performed in this block is propagated
so that the type checker knows that the type of the block (which will be
identified as `()`) shouldn't be checked against the expectation to
reduce the amount of irrelevant diagnostic errors shown to the user.
Fix#44579.
When a parse error occurs on a block, the parser will recover and create
a block with the statements collected until that point. Now a flag
stating that a recovery has been performed in this block is propagated
so that the type checker knows that the type of the block (which will be
identified as `()`) shouldn't be checked against the expectation to
reduce the amount of irrelevant diagnostic errors shown to the user.
Generics refactoring (groundwork for const generics)
These changes were suggested by @eddyb.
After this change, the `Generics` contain one `Vec` of an enum for the generic parameters, rather than two separate `Vec`s for lifetime and type parameters. Type params and const params will need to be in a shared `Vec` to preserve their ordering, and moving lifetimes into the same `Vec` should simplify the code that processes `Generics`.
tweaks and fixes for doc(include)
This PR makes a handful of changes around `#[doc(include="file.md")]` (https://github.com/rust-lang/rust/issues/44732):
* Turns errors when loading files into full errors. This matches the original RFC text.
* Makes the `missing_docs` lint check for `#[doc(include="file.md")]` as well as regular `#[doc="text"]` attributes.
* Loads files included by `#[doc(include="file.md")]` into dep-info, mirroring the behavior of `include_str!()` and friends.
* Adds or modifies tests to check for all of these.
incr.comp.: Precompute small hash for filenames to save some work.
For each span we hash the filename of the file it points to. Since filenames can be quite long, especially with absolute paths, this PR pre-computes a hash of the filename and we then only hash the hash.
r? @nikomatsakis
The Generics now contain one Vec of an enum for the generic parameters,
rather than two separate Vec's for lifetime and type parameters.
Additionally, places that previously used Vec<LifetimeDef> now use
Vec<GenericParam> instead.
syntax: Follow-up to the incorrect qpath recovery PR
cc https://github.com/rust-lang/rust/pull/46788
Add tests checking that "priority" of qpath recovery is higher than priority of unary and binary operators
Fix regressed parsing of paths with fn-like generic arguments
r? @estebank
Implement non-mod.rs mod statements
Fixes https://github.com/rust-lang/rust/issues/45385, cc https://github.com/rust-lang/rust/issues/44660
This will fail tidy right now because it doesn't recognize my UI tests as feature-gate tests. However, I'm not sure if compile-fail will work out either because compile-fail usually requires there to be error patterns in the top-level file, which isn't possible with this feature. What's the recommended way to handle this?
trait alias infrastructure
This will be an implementation of trait aliases (RFC 1733, #41517).
Progress so far:
- [x] Feature gate
- [x] Add to parser
- [x] `where` clauses
- [x] prohibit LHS type parameter bounds via AST validation https://github.com/rust-lang/rust/pull/45047#discussion_r143575575
- [x] Add to AST and HIR
- [x] make a separate PathSource for trait alias contexts https://github.com/rust-lang/rust/pull/45047#discussion_r143353932
- [x] Stub out enough of typeck and resolve to just barely not ICE
Postponed:
- [ ] Actually implement the alias part
- [ ] #21903
- [ ] #24010
I need some pointers on where to start with that last one. The test currently does this:
```
error[E0283]: type annotations required: cannot resolve `_: CD`
--> src/test/run-pass/trait-alias.rs:34:16
|
34 | let both = foo();
| ^^^
|
= note: required by `foo`
```
macros: hygienize use of `core`/`std` in builtin macros
Today, if a builtin macro wants to access an item from `core` or `std` (depending `#![no_std]`), it generates `::core::path::to::item` or `::std::path::to::item` respectively (c.f. `fn std_path()` in `libsyntax/ext/base.rs`).
This PR refactors the builtin macros to instead always emit `$crate::path::to::item` here. That is, the def site of builtin macros is taken to be in `extern crate core;` or `extern crate std;`. Since builtin macros are macros 1.0 (i.e. mostly unhygienic), changing the def site can only effect the resolution of `$crate`.
r? @nrc
