add `unused_braces` lint
Add the lint `unused_braces` which is warn by default.
`unused_parens` is also extended and now checks anon consts.
closes#68387
r? @varkor
BTreeMap/BTreeSet: implement drain_filter
Provide an implementation of drain_filter for BTreeMap and BTreeSet. Should be optimal when the predicate picks only elements in leaf nodes with at least MIN_LEN remaining elements, which is a common case, at least when draining only a fraction of the map/set, and also when the predicate picks elements stored in internal nodes where the right subtree can easily let go of a replacement element.
The first commit adds benchmarks with an external, naive implementation. to compare how much this claimed optimality-in-some-cases is actually worth.
Rollup of 7 pull requests
Successful merges:
- #69425 (add fn make_contiguous to VecDeque)
- #69458 (improve folder name for persistent doc tests)
- #70268 (Document ThreadSanitizer in unstable-book)
- #70600 (Ensure there are versions of test code for aarch64 windows)
- #70606 (Clean up E0466 explanation)
- #70614 (remove unnecessary relocation check in const_prop)
- #70623 (Fix broken link in README)
Failed merges:
r? @ghost
Ensure there are versions of test code for aarch64 windows
Remove the `cfg` flags that were preventing some tests from running on `aarch64-pc-windows-msvc`.
All the existing `target_os = windows` targets had the same `align()` and `size()` values, so this change just removes the `target_arch` flags.
r? @alexcrichton
improve folder name for persistent doc tests
This fixes#69411, by using the entire path as folder name and storing already visited paths in a HashMap + appending a number to the file name for duplicates.
more clippy fixes
* use is_empty() instead of len comparison (clippy::len_zero)
* use if let instead of while let loop that never loops (clippy::never_loop)
* remove redundant returns (clippy::needless_return)
* remove redundant closures (clippy::redundant_closure)
* use if let instead of match and wildcard pattern (clippy::single_match)
* don't repeat field names redundantly (clippy::redundant_field_names)
r? @Centril
Fix incorrect documentation for `str::{split_at, split_at_mut}`
The documentation for each method currently states:
> Panics if `mid` is not on a UTF-8 code point boundary, or if it is beyond the last code point of the string slice.
However, this is not consistent with the real behavior, or that of the corresponding methods for `[T]` slices. A comment inside each of the `str` methods states:
> is_char_boundary checks that the index is in [0, .len()]
That is what I would expect the behavior to be, and in fact this seems to be the real behavior. For example ([playground](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=8e03dcc209d4dd176df2297523f9fee1)):
```rust
fn main() {
// Prints ("abc", "") and doesn't panic
println!("{:?}", "abc".split_at(3));
}
```
In this case, I would interpret "the last code point of the string slice" to mean the byte at index 2 in UTF-8. However, it is possible to pass an index of 3, which is definitely "beyond the last code point of the string slice".
I think that this is much clearer, but feel free to bikeshed.
Add `Rust` to the code snippet
Adds `Rust` to the snippet where the code causing the ICE should be placed, so github can render it as Rust code rather than plain code.
std: Fix over-aligned allocations on wasm32-wasi
The wasm32-wasi target delegates its malloc implementation to the
functions in wasi-libc, but the invocation of `aligned_alloc` was
incorrect by passing the number of bytes requested first rather than the
alignment. This commit swaps the order of these two arguments to ensure
that we allocate over-aligned memory correctly.
infer array len from pattern
closes#70529
This still errors in the following case
```rust
#![feature(const_generics)]
fn arr<const N: usize>() -> [u8; N] {
todo!()
}
fn main() {
match arr() {
[5, ..] => (),
//~^ ERROR cannot pattern-match on an array without a fixed length
[_, _] => (),
}
}
```
Considering that this should be rare and is harder to implement I would merge this PR without *fixing* the above.
Add long error code for error E0226
Added a long description message for error E0226, which previously did not exist.
As requested in issue #61137
r? @GuillaumeGomez
Optimize strip_prefix and strip_suffix with str patterns
As mentioned in https://github.com/rust-lang/rust/issues/67302#issuecomment-585639226.
I'm not sure whether adding these methods to `Pattern` is desirable—but they have default implementations so the change is backwards compatible. Plus it seems like they're slated for wholesale replacement soon anyway? #56345
----
Constructing a Searcher in strip_prefix and strip_suffix is
unnecessarily slow when the pattern is a fixed-length string. Add
strip_prefix and strip_suffix methods to the Pattern trait, and add
optimized implementations of these methods in the str implementation.
The old implementation is retained as the default for these methods.
use is_empty() instead of len comparison (clippy::len_zero)
use if let instead of while let loop that never loops (clippy::never_loop)
remove redundant returns (clippy::needless_return)
remove redundant closures (clippy::redundant_closure)
use if let instead of match and wildcard pattern (clippy::single_match)
don't repeat field names redundantly (clippy::redundant_field_names)
The wasm32-wasi target delegates its malloc implementation to the
functions in wasi-libc, but the invocation of `aligned_alloc` was
incorrect by passing the number of bytes requested first rather than the
alignment. This commit swaps the order of these two arguments to ensure
that we allocate over-aligned memory correctly.
Constructing a Searcher in strip_prefix and strip_suffix is
unnecessarily slow when the pattern is a fixed-length string. Add
strip_prefix and strip_suffix methods to the Pattern trait, and add
optimized implementations of these methods in the str implementation.
The old implementation is retained as the default for these methods.
Polonius: update to 0.12.1, fix more move errors false positives, update test expectations
This PR:
- updates `polonius-engine` to version 0.12.1 to fix some move errors false positives
- fixes a fact generation mistake creating the other move errors false positives
- updates the test expectations for the polonius compare-mode so that all (minus the 2 OOMs) ui tests pass again (matching the [analysis doc](https://hackmd.io/CjYB0fs4Q9CweyeTdKWyEg?view) starting at case 34)
In my opinion, this is safe to rollup.
r? @nikomatsakis
