Make the `const_err` lint `deny`-by-default
At best these things are runtime panics (debug mode) or overflows (release mode). More likely they are public constants that are unused in the crate declaring them.
This is not a breaking change, as dependencies won't break and root crates can `#![warn(const_err)]`, though I don't know why anyone would do that.
Implement edition hygiene for keywords
Determine "keywordness" of an identifier in its hygienic context.
cc https://github.com/rust-lang/rust/pull/49611
I've resurrected `proc` as an Edition-2015-only keyword for testing purposes, but it should probably be buried again. EDIT: `proc` is removed again.
stop considering location when computing outlives relationships
This doesn't (yet?) use SEME regions, but it does ignore the location for outlives constraints. This makes (I believe) NLL significantly faster -- but we should do some benchmarks. It regresses the "get-default" family of use cases for NLL, which is a shame, but keeps the other benefits, and thus represents a decent step forward.
r? @pnkfelix
Improve format string errors
Point at format string position inside the formatting string:
```
error: invalid format string: unmatched `}` found
--> $DIR/format-string-error.rs:21:22
|
LL | let _ = format!("}");
| ^ unmatched `}` in format string
```
Explain that argument names can't start with an underscore:
```
error: invalid format string: invalid argument name `_foo`
--> $DIR/format-string-error.rs:15:23
|
LL | let _ = format!("{_foo}", _foo = 6usize);
| ^^^^ invalid argument name in format string
|
= note: argument names cannot start with an underscore
```
Fix#23476.
The more accurate spans will only be seen when using `format!` directly, when using `println!` the diagnostics machinery makes the span be the entire statement.
compiletest: Run revisions as independent tests.
Fixes#47604.
- The output of each test is now in its own directory.
- "auxiliary" output is now under the respective test directory.
- `stage_id` removed from filenames, and instead placed in the stamp file as a hash. This helps keep path lengths down for Windows.
In brief, the new layout looks like this:
```
<build_base>/<relative_dir>/<testname>.<revision>.<mode>/
stamp
<testname>.err
<testname>.out
a (binary)
auxiliary/lib<auxname>.dylib
auxiliary/<auxname>/<auxname>.err
auxiliary/<auxname>/<auxname>.out
```
(revision and mode are optional)
- The output of each test is now in its own directory.
- "auxiliary" output is now under the respective test directory.
- `stage_id` removed from filenames, and instead placed in the stamp file as a hash. This helps keep path lengths down for Windows.
In brief, the new layout looks like this:
```
<build_base>/<relative_dir>/<testname>.<revision>.<mode>/
stamp
<testname>.err
<testname>.out
a (binary)
auxiliary/lib<auxname>.dylib
auxiliary/<auxname>/<auxname>.err
auxiliary/<auxname>/<auxname>.out
```
(revision and mode are optional)
rustc: Fix `crate` lint for single-item paths
This commit fixes recommending the `crate` prefix when migrating to 2018 for
paths that look like `use foo;` or `use {bar, baz}`
Closes#50660
tidy: Add a check for empty UI test files
Check for empty `.stderr` and `.stdout` files in UI test directories.
Empty files could still pass testing for `compile-pass` tests with no output
so they can get into the repo accidentally, but they are not necessary and can
be removed.
This is very much an in progress pull request. I'm having an issue with rustfmt. It wanted to reformat the entire file for almost every file by default. And when I run tidy it just errors out because it catches the empty files that are already in the repo.
My next step is goin got be to remove those empty file and see if running tidy again will actually reformat things outside of the context of `cargo fmt`
Fixes https://github.com/rust-lang/rust/issues/50785
Fix `fn main() -> impl Trait` for non-`Termination` trait
Fixes#50595.
This bug currently affects stable. Why I think we can go for hard error:
- It will in stable for at most one cycle and there is no legitimate reason to abuse it, nor any known uses in the wild.
- It only affects `bin` crates (which have a `main`), so there is little practical difference between a hard error or a deny lint, both are a one line fix.
The fix was to just unshadow a variable. Thanks @nikomatsakis for the mentoring!
r? @nikomatsakis
Implement RFC 2056 trivial constraints in where clauses
This is an implementation of the new behaviour for #48214. Tests are mostly updated to show the effects of this. Feature gate hasn't been added yet.
Some things that are worth noting and are maybe not want we want
* `&mut T: Copy` doesn't allow as much as someone might expect because there is often an implicit reborrow.
* ~There isn't a check that a where clause is well-formed any more, so `where Vec<str>: Debug` is now allowed (without a `str: Sized` bound).~
r? @nikomatsakis
The Great Generics Generalisation: Ty Edition
Part of the generic parameter refactoring effort, split off from https://github.com/rust-lang/rust/pull/48149. Contains the `ty`-relative refactoring.
r? @eddyb
Improve eager type resolution error message
This PR improves the span of eager resolution type errors referring to indexing and field access to use the base span rather than the whole expression.
Also a "note: type must be known at this point" is added where in the past we emitted the "type must be known at this context" error, so that early failures can be differentiated and will hopefully be less surprising.
Fixes#50692 (or at least does the best we can for the moment)
r? @estebank
