Implement destructuring assignment for structs and slices
This is the second step towards implementing destructuring assignment (RFC: rust-lang/rfcs#2909, tracking issue: #71126). This PR is the second part of #71156, which was split up to allow for easier review.
Note that the first PR (#78748) is not merged yet, so it is included as the first commit in this one. I thought this would allow the review to start earlier because I have some time this weekend to respond to reviews. If ``@petrochenkov`` prefers to wait until the first PR is merged, I totally understand, of course.
This PR implements destructuring assignment for (tuple) structs and slices. In order to do this, the following *parser change* was necessary: struct expressions are not required to have a base expression, i.e. `Struct { a: 1, .. }` becomes legal (in order to act like a struct pattern).
Unfortunately, this PR slightly regresses the diagnostics implemented in #77283. However, it is only a missing help message in `src/test/ui/issues/issue-77218.rs`. Other instances of this diagnostic are not affected. Since I don't exactly understand how this help message works and how to fix it yet, I was hoping it's OK to regress this temporarily and fix it in a follow-up PR.
Thanks to ``@varkor`` who helped with the implementation, particularly around the struct rest changes.
r? ``@petrochenkov``
Do not collect tokens for doc comments
Doc comment is a single token and AST has all the information to re-create it precisely.
Doc comments are also responsible for majority of calls to `collect_tokens` (with `num_calls == 1` and `num_calls == 0`, cc https://github.com/rust-lang/rust/pull/78736).
(I also moved token collection into `fn parse_attribute` to deduplicate code a bit.)
r? `@Aaron1011`
Add `let_underscore_drop`
This line generalizes `let_underscore_lock` (#5101) to warn about any initializer expression that implements `Drop`.
So, for example, the following would generate a warning:
```rust
struct Droppable;
impl Drop for Droppable {
fn drop(&mut self) {}
}
let _ = Droppable;
```
I tried to preserve the original `let_underscore_lock` functionality in the sense that the warning generated for
```rust
let _ = mutex.lock();
```
should be unchanged.
*Please keep the line below*
changelog: Add lint [`let_underscore_drop`]
rustc_ast: Do not panic by default when visiting macro calls
Panicking by default made sense when we didn't have HIR or MIR and everything worked on AST, but now all AST visitors run early and majority of them have to deal with macro calls, often by ignoring them.
The second commit renames `visit_mac` to `visit_mac_call`, the corresponding structures were renamed earlier in https://github.com/rust-lang/rust/pull/69589.
Fix bad suggestions for `deref_addrof` and `try_err` lints
Fix bad suggestions when in macro expansion for `deref_addrof` and `try_err` lints.
Fixes: #6234Fixes: #6242Fixes: #6237
changelog: none
r? `@llogiq`
Fix example used in cargo_common_metadata
The previous example used in `cargo_common_metadata` included an authors field, even though the comment says it doesn't. And thus doesn't actually demonstrate an example of how the lint fails.
This removes that authors field from the _bad_ example and suggest to fix the _bad_ example by adding the authors field
changelog: Fix example used in `cargo_common_metadata`
We skip the lint if the `loop {}` is in the `#[panic_handler]` as the
main recommendation we give is to panic, which obviously isn't
possible in a panic handler.
Signed-off-by: Joe Richey <joerichey@google.com>
Check when `from_utf8` is called from sliced byte array from string
---
*Please keep the line below*
changelog: Fix#5487: Add linter to check when `from_utf8` is called from sliced byte array from string.
"Respect" enums in `interior_mutable_const`
fixes#3962fixes#3825
Hello,
It might not be a good idea to submit another relatively large PR while I have an opened PR; but, I've finished this anyway. This may be able to wait for months.
Note: the code uses the MIR interpreter, which the author of #3962 thought unlikely to be a solution. This might be over-engineering; but, I think it's important to be able to work with the 'http' crate (#3825). (And, I don't want to write a MIR visitor)
---
changelog: fix a false positive in two `interior_mutable_const` lints where a constant with enums gets linted
even if it uses a clearly unfrozen variant
Provide diagnostic suggestion in ExprUseVisitor Delegate
The [Delegate trait](981346fc07/compiler/rustc_typeck/src/expr_use_visitor.rs (L28-L38)) currently use `PlaceWithHirId` which is composed of Hir `Place` and the
corresponding expression id.
Even though this is an accurate way of expressing how a Place is used,
it can cause confusion during diagnostics.
Eg:
```
let arr : [String; 5];
let [a, ...] = arr;
^^^ E1 ^^^ = ^^E2^^
```
Here `arr` is moved because of the binding created E1. However, when we
point to E1 in diagnostics with the message `arr` was moved, it can be
confusing. Rather we would like to report E2 to the user.
Closes: https://github.com/rust-lang/project-rfc-2229/issues/20
r? `@ghost`
Add lint for 'field_reassign_with_default` #568
changelog: Add lint for field_reassign_with_default that checks if mutable object + field modification is used to edit a binding initialized with Default::default() instead of struct constructor.
Fixes#568
Notes:
- Checks for reassignment of one or more fields of a binding initialized with Default::default().
- Implemented using EarlyLintPass, might be future proofed better with LateLintPass.
- Does not trigger if Default::default() is used via another type implementing Default.
- This is a re-open of [PR#4761](https://github.com/rust-lang/rust-clippy/pull/4761), but I couldn't figure out how to re-open that one so here's a new one with the requested changes :S
