Add `std_instead_of_core`, `std_instead_of_alloc`, `alloc_instead_of_core`
Closes#7724
Introduces 3 new lints:
- `std_instead_of_core` - lints items resolved through `std` which are available in `core`
- `std_instead_of_alloc` - lints items resolved through `std` which are available in `alloc`
- `alloc_instead_of_core` - lints items resolved through `alloc` which are available in `core`
Though the original issue only mentions `std_instead_of_alloc`, the other two lints could be useful as well.
questions:
- what do I call the file the lints live in? I was thinking `std_reexports`?
changelog: new lint's: [`std_instead_of_core`], [`std_instead_of_alloc`], [`alloc_instead_of_core`]
[`box_collection`]: raise warn for all std collections
So far, only [`Vec`, `String`, `HashMap`] were considered.
Extend collection checklist for this lint with:
- `HashSet`
- `VecDeque`
- `LinkedList`
- `BTreeMap`
- `BTreeSet`
- `BinaryHeap`
changelog: [`box_collection`]: raise warn for all std collections
Move format_push_string to restriction
Fixes#9077 (kinda) by moving the lint to the restriction group. As I noted in that issue, I think the suggested change is too much and as the OP of the issue points out, the ramifications of the change are not necessarily easily understood. As such I don't think the lint should be enabled by default.
changelog: [`format_push_string`]: moved to restriction (see #9077).
Implement `for<>` lifetime binder for closures
This PR implements RFC 3216 ([TI](https://github.com/rust-lang/rust/issues/97362)) and allows code like the following:
```rust
let _f = for<'a, 'b> |a: &'a A, b: &'b B| -> &'b C { b.c(a) };
// ^^^^^^^^^^^--- new!
```
cc ``@Aaron1011`` ``@cjgillot``
Always create elided lifetime parameters for functions
Anonymous and elided lifetimes in functions are sometimes (async fns) --and sometimes not (regular fns)-- desugared to implicit generic parameters.
This difference of treatment makes it some downstream analyses more complicated to handle. This step is a pre-requisite to perform lifetime elision resolution on AST.
There is currently an inconsistency in the treatment of argument-position impl-trait for functions and async fns:
```rust
trait Foo<'a> {}
fn foo(t: impl Foo<'_>) {} //~ ERROR missing lifetime specifier
async fn async_foo(t: impl Foo<'_>) {} //~ OK
fn bar(t: impl Iterator<Item = &'_ u8>) {} //~ ERROR missing lifetime specifier
async fn async_bar(t: impl Iterator<Item = &'_ u8>) {} //~ OK
```
The current implementation reports "missing lifetime specifier" on `foo`, but **accepts it** in `async_foo`.
This PR **proposes to accept** the anonymous lifetime in both cases as an extra generic lifetime parameter.
This change would be insta-stable, so let's ping t-lang.
Anonymous lifetimes in GAT bindings keep being forbidden:
```rust
fn foo(t: impl Foo<Assoc<'_> = Bar<'_>>) {}
^^ ^^
forbidden ok
```
I started a discussion here: https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Anonymous.20lifetimes.20in.20universal.20impl-trait/near/284968606
r? ``@petrochenkov``
Pull Derefer before ElaborateDrops
_Follow up work to #97025#96549#96116#95887 #95649_
This moves `Derefer` before `ElaborateDrops` and creates a new `Rvalue` called `VirtualRef` that allows us to bypass many constraints for `DerefTemp`.
r? `@oli-obk`
Use `LazyLock` for `lint_message_convention` regexes
They were being recompiled for `Message::new` call, for me this shaves 7s off the time it takes to run the test. Also removes a redundant exception from the list and joins the various `message...` exceptions into one
changelog: none
Lower let-else in MIR
This MR will switch to lower let-else statements in MIR building instead.
To lower let-else in MIR, we build a mini-switch two branches. One branch leads to the matching case, and the other leads to the `else` block. This arrangement will allow temporary lifetime analysis running as-is so that the temporaries are properly extended according to the same rule applied to regular `let` statements.
cc https://github.com/rust-lang/rust/issues/87335Fix#98672
fix [`manual_flatten`] help texts order
fixes #8948
Whenever suggestion for this lint does not fit in one line,
legacy solution has some unexpected/unhandled behavior:
lint will then generate two help messages which seem to be shown in the wrong order.
The second help message in that case will contain the suggestion.
The first help message always refers to a suggestion message,
and **it should adapt** depending on the location of the suggestion:
- inline suggestion within the error/warning message
- suggestion separated into a second help text
This is my first contribution here, so I hope I didn't miss anything for creating this PR.
changelog: fix [`manual_flatten`] help texts order
Build the Clippy book as part of x.py doc
r? ``@ehuss`` since you said you would be interested in helping moving this forward.
cc ``@jyn514`` as part of the bootstrap team.
Whenever suggestion for this lint does not fit in one line,
lint will generate two help messages. The second help message
will always contain the suggestion.
The first help message refers to suggestion message,
and it should adapt depending on the location of the suggestion:
- inline suggestion within the error/warning message
- suggestion separated into second help text
Add `repeated_where_clause_or_trait_bound` lint
I thought I would try and scratch my own itch for #8674.
1. Is comparing the `Res` the correct way for ensuring we have the same trait?
2. Is there a way to get the spans for the bounds and clauses for suggestions?
I tried to use `GenericParam::bounds_span_for_suggestions` but it only gave me an empty span at the end of the spans.
I tried `WhereClause::span_for_predicates_or_empty_place` and it included the comma.
3. Is there a simpler way to get the trait names? I have used the spans of the traits because I didn't see a way to get it off the `Res` or `Def`.
changelog: Add ``[`repeated_where_clause_or_trait_bound`]`` lint.
change applicability type to MaybeIncorrect in `explicit_counter_loop`
close#9013
This PR changes applicability type to `MaybeIncorrect`, because the suggestion is not `MachineApplicable`.
changelog: change applicability type to MaybeIncorrect in `explicit_counter_loop`
Fixes for `branches_sharing_code`
fixes#7198fixes#7452fixes#7555fixes#7589
changelog: Don't suggest moving modifications to locals used in any of the condition expressions in `branches_sharing_code`
changelog: Don't suggest moving anything after a local with a significant drop in `branches_sharing_code`
