When both `std::` and `core::` items are available, only suggest the
`std::` ones. We ensure that in `no_std` crates we suggest `core::`
items.
Ensure that the list of items suggested to be imported are always in the
order of local crate items, `std`/`core` items and finally foreign crate
items.
Tweak wording of import suggestion: if there are multiple items but they
are all of the same kind, we use the kind name and not the generic "items".
Fix#83564.
Spruce up the diagnostics of some early lints
Implement the various "*(note to myself) in a follow-up PR we should turn parts of this message into a subdiagnostic (help msg or even struct sugg)*" drive-by comments I left in #124417 during my review.
For context, before #124417, only a few early lints touched/decorated/customized their diagnostic because the former API made it a bit awkward. Likely because of that, things that should've been subdiagnostics were just crammed into the primary message. This PR rectifies this.
Change the algorithm which determines whether a self lifetime can be
used for return type lifetime elision, such that we consider lifetimes
attached to any reference in the self type, so long as Self can be found
anywhere inside the type of that reference.
Rollup of 9 pull requests
Successful merges:
- #124840 (resolve: mark it undetermined if single import is not has any bindings)
- #125622 (Winnow private method candidates instead of assuming any candidate of the right name will apply)
- #125648 (Remove unused(?) `~/rustsrc` folder from docker script)
- #125672 (Add more ABI test cases to miri (RFC 3391))
- #125800 (Fix `mut` static task queue in SGX target)
- #125871 (Orphanck[old solver]: Consider opaque types to never cover type parameters)
- #125893 (Handle all GVN binops in a single place.)
- #126008 (Port `tests/run-make-fulldeps/issue-19371` to ui-fulldeps)
- #126032 (Update description of the `IsTerminal` example)
r? `@ghost`
`@rustbot` modify labels: rollup
resolve: mark it undetermined if single import is not has any bindings
- Fixes#124490
- Fixes#125013
This issue arises from incorrect resolution updates, for example:
```rust
mod a {
pub mod b {
pub mod c {}
}
}
use a::*;
use b::c;
use c as b;
fn main() {}
```
1. In the first loop, binding `(root, b)` is refer to `root:🅰️:b` due to `use a::*`.
1. However, binding `(root, c)` isn't defined by `use b::c` during this stage because `use c as b` falls under the `single_imports` of `(root, b)`, where the `imported_module` hasn't been computed yet. This results in marking the `path_res` for `b` as `Indeterminate`.
2. Then, the `imported_module` for `use c as b` will be recorded.
2. In the second loop, `use b::c` will be processed again:
1. Firstly, it attempts to find the `path_res` for `(root, b)`.
2. It will iterate through the `single_imports` of `use b::c`, encounter `use c as b`, attempt to resolve `c` in `root`, and ultimately return `Err(Undetermined)`, thus passing the iterator.
3. Use the binding `(root, b)` -> `root:🅰️:b` introduced by `use a::*` and ultimately return `root:🅰️:b` as the `path_res` of `b`.
4. Then define the binding `(root, c)` -> `root:🅰️🅱️:c`.
3. Then process `use c as b`, update the resolution for `(root, b)` to refer to `root:🅰️🅱️:c`, ultimately causing inconsistency.
In my view, step `2.2` has an issue where it should exit early, similar to the behavior when there's no `imported_module`. Therefore, I've added an attribute called `indeterminate` to `ImportData`. This will help us handle only those single imports that have at least one determined binding.
r? ``@petrochenkov``
Detect when user is trying to create a lending `Iterator` and give a custom explanation
The scope for this diagnostic is to detect lending iterators specifically and it's main goal is to help beginners to understand that what they are trying to implement might not be possible for `Iterator` trait specifically.
I ended up to changing the wording from originally proposed in the ticket because it might be misleading otherwise: `Data` might have a lifetime parameter but it can be unrelated to items user is planning to return.
Fixes https://github.com/rust-lang/rust/issues/125337
Improve renaming suggestion for names with leading underscores
Fixes#125650
Before:
```
error[E0425]: cannot find value `p` in this scope
--> test.rs:2:13
|
2 | let _ = p;
| ^
|
help: a local variable with a similar name exists, consider renaming `_p` into `p`
|
1 | fn a(p: i32) {
| ~
```
After:
```
error[E0425]: cannot find value `p` in this scope
--> test.rs:2:13
|
1 | fn a(_p: i32) {
| -- `_p` defined here
2 | let _ = p;
| ^
|
help: the leading underscore in `_p` marks it as unused, consider renaming it to `p`
|
1 | fn a(p: i32) {
| ~
```
This change doesn't exactly conform to what was proposed in the issue:
1. I've kept the suggested code instead of solely replacing it with the label
2. I've removed the "...similar name exists..." message instead of relocating to the usage span
3. You could argue that it still isn't completely clear that the change is referring to the definition (not the usage), but I'm not sure how to do this without playing down the fact that the error was caused by the usage of an undefined name.
Rename HIR `TypeBinding` to `AssocItemConstraint` and related cleanup
Rename `hir::TypeBinding` and `ast::AssocConstraint` to `AssocItemConstraint` and update all items and locals using the old terminology.
Motivation: The terminology *type binding* is extremely outdated. "Type bindings" not only include constraints on associated *types* but also on associated *constants* (feature `associated_const_equality`) and on RPITITs of associated *functions* (feature `return_type_notation`). Hence the word *item* in the new name. Furthermore, the word *binding* commonly refers to a mapping from a binder/identifier to a "value" for some definition of "value". Its use in "type binding" made sense when equality constraints (e.g., `AssocTy = Ty`) were the only kind of associated item constraint. Nowadays however, we also have *associated type bounds* (e.g., `AssocTy: Bound`) for which the term *binding* doesn't make sense.
---
Old terminology (HIR, rustdoc):
```
`TypeBinding`: (associated) type binding
├── `Constraint`: associated type bound
└── `Equality`: (associated) equality constraint (?)
├── `Ty`: (associated) type binding
└── `Const`: associated const equality (constraint)
```
Old terminology (AST, abbrev.):
```
`AssocConstraint`
├── `Bound`
└── `Equality`
├── `Ty`
└── `Const`
```
New terminology (AST, HIR, rustdoc):
```
`AssocItemConstraint`: associated item constraint
├── `Bound`: associated type bound
└── `Equality`: associated item equality constraint OR associated item binding (for short)
├── `Ty`: associated type equality constraint OR associated type binding (for short)
└── `Const`: associated const equality constraint OR associated const binding (for short)
```
r? compiler-errors
Reintroduce name resolution check for trying to access locals from an inline const
fixes#125676
I removed this without replacement in https://github.com/rust-lang/rust/pull/124650 without considering the consequences
Silence some resolve errors when there have been glob import errors
When encountering `use foo::*;` where `foo` fails to be found, and we later encounter resolution errors, we silence those later errors.
A single case of the above, for an *existing* import on a big codebase would otherwise have a huge number of knock-down spurious errors.
Ideally, instead of a global flag to silence all subsequent resolve errors, we'd want to introduce an unnameable binding in the appropriate rib as a sentinel when there's a failed glob import, so when we encounter a resolve error we can search for that sentinel and if found, and only then, silence that error. The current approach is just a quick proof of concept to iterate over.
Partially address #96799.
When encountering `use foo::*;` where `foo` fails to be found, and we later
encounter resolution errors, we silence those later errors.
A single case of the above, for an *existing* import on a big codebase would
otherwise have a huge number of knock-down spurious errors.
Ideally, instead of a global flag to silence all subsequent resolve errors,
we'd want to introduce an unameable binding in the appropriate rib as a
sentinel when there's a failed glob import, so when we encounter a resolve
error we can search for that sentinel and if found, and only then, silence
that error. The current approach is just a quick proof of concept to
iterate over.
Partially address #96799.
Expand `for_loops_over_fallibles` lint to lint on fallibles behind references.
Extends the scope of the (warn-by-default) lint `for_loops_over_fallibles` from just `for _ in x` where `x: Option<_>/Result<_, _>` to also cover `x: &(mut) Option<_>/Result<_>`
```rs
fn main() {
// Current lints
for _ in Some(42) {}
for _ in Ok::<_, i32>(42) {}
// New lints
for _ in &Some(42) {}
for _ in &mut Some(42) {}
for _ in &Ok::<_, i32>(42) {}
for _ in &mut Ok::<_, i32>(42) {}
// Should not lint
for _ in Some(42).into_iter() {}
for _ in Some(42).iter() {}
for _ in Some(42).iter_mut() {}
for _ in Ok::<_, i32>(42).into_iter() {}
for _ in Ok::<_, i32>(42).iter() {}
for _ in Ok::<_, i32>(42).iter_mut() {}
}
```
<details><summary><code>cargo build</code> diff</summary>
```diff
diff --git a/old.out b/new.out
index 84215aa..ca195a7 100644
--- a/old.out
+++ b/new.out
`@@` -1,33 +1,93 `@@`
warning: for loop over an `Option`. This is more readably written as an `if let` statement
--> src/main.rs:3:14
|
3 | for _ in Some(42) {}
| ^^^^^^^^
|
= note: `#[warn(for_loops_over_fallibles)]` on by default
help: to check pattern in a loop use `while let`
|
3 | while let Some(_) = Some(42) {}
| ~~~~~~~~~~~~~~~ ~~~
help: consider using `if let` to clear intent
|
3 | if let Some(_) = Some(42) {}
| ~~~~~~~~~~~~ ~~~
warning: for loop over a `Result`. This is more readably written as an `if let` statement
--> src/main.rs:4:14
|
4 | for _ in Ok::<_, i32>(42) {}
| ^^^^^^^^^^^^^^^^
|
help: to check pattern in a loop use `while let`
|
4 | while let Ok(_) = Ok::<_, i32>(42) {}
| ~~~~~~~~~~~~~ ~~~
help: consider using `if let` to clear intent
|
4 | if let Ok(_) = Ok::<_, i32>(42) {}
| ~~~~~~~~~~ ~~~
-warning: `for-loops-over-fallibles` (bin "for-loops-over-fallibles") generated 2 warnings
- Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.04s
+warning: for loop over a `&Option`. This is more readably written as an `if let` statement
+ --> src/main.rs:7:14
+ |
+7 | for _ in &Some(42) {}
+ | ^^^^^^^^^
+ |
+help: to check pattern in a loop use `while let`
+ |
+7 | while let Some(_) = &Some(42) {}
+ | ~~~~~~~~~~~~~~~ ~~~
+help: consider using `if let` to clear intent
+ |
+7 | if let Some(_) = &Some(42) {}
+ | ~~~~~~~~~~~~ ~~~
+
+warning: for loop over a `&mut Option`. This is more readably written as an `if let` statement
+ --> src/main.rs:8:14
+ |
+8 | for _ in &mut Some(42) {}
+ | ^^^^^^^^^^^^^
+ |
+help: to check pattern in a loop use `while let`
+ |
+8 | while let Some(_) = &mut Some(42) {}
+ | ~~~~~~~~~~~~~~~ ~~~
+help: consider using `if let` to clear intent
+ |
+8 | if let Some(_) = &mut Some(42) {}
+ | ~~~~~~~~~~~~ ~~~
+
+warning: for loop over a `&Result`. This is more readably written as an `if let` statement
+ --> src/main.rs:9:14
+ |
+9 | for _ in &Ok::<_, i32>(42) {}
+ | ^^^^^^^^^^^^^^^^^
+ |
+help: to check pattern in a loop use `while let`
+ |
+9 | while let Ok(_) = &Ok::<_, i32>(42) {}
+ | ~~~~~~~~~~~~~ ~~~
+help: consider using `if let` to clear intent
+ |
+9 | if let Ok(_) = &Ok::<_, i32>(42) {}
+ | ~~~~~~~~~~ ~~~
+
+warning: for loop over a `&mut Result`. This is more readably written as an `if let` statement
+ --> src/main.rs:10:14
+ |
+10 | for _ in &mut Ok::<_, i32>(42) {}
+ | ^^^^^^^^^^^^^^^^^^^^^
+ |
+help: to check pattern in a loop use `while let`
+ |
+10 | while let Ok(_) = &mut Ok::<_, i32>(42) {}
+ | ~~~~~~~~~~~~~ ~~~
+help: consider using `if let` to clear intent
+ |
+10 | if let Ok(_) = &mut Ok::<_, i32>(42) {}
+ | ~~~~~~~~~~ ~~~
+
+warning: `for-loops-over-fallibles` (bin "for-loops-over-fallibles") generated 6 warnings
+ Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.02s
```
</details>
-----
Question:
* ~~Currently, the article `an` is used for `&Option`, and `&mut Option` in the lint diagnostic, since that's what `Option` uses. Is this okay or should it be changed? (likewise, `a` is used for `&Result` and `&mut Result`)~~ The article `a` is used for `&Option`, `&mut Option`, `&Result`, `&mut Result` and (as before) `Result`. Only `Option` uses `an` (as before).
`@rustbot` label +A-lint
This makes a small change as requested in code review, such that if there's
ambiguity in the self lifetime, we avoid lifetime elision entirely instead of
considering using lifetimes from any of the other parameters.
For example,
impl Something {
fn method(self: &Box<&Self>, something_else: &u32) -> &u32 { ... }
}
in standard Rust would have assumed the return lifetime was that of &Self;
with this PR prior to this commit would have chosen the lifetime of
'something_else', and after this commit would give an error message explaining
that the lifetime is ambiguous.
struct Concrete(u32);
impl Concrete {
fn m(self: &Box<Self>) -> &u32 {
&self.0
}
}
resulted in a confusing error.
impl Concrete {
fn n(self: &Box<&Self>) -> &u32 {
&self.0
}
}
resulted in no error or warning, despite apparent ambiguity over the elided
lifetime.
This commit changes two aspects of the behavior.
Previously, when examining the self type, we considered lifetimes only if they
were immediately adjacent to Self. We now consider lifetimes anywhere in the
self type.
Secondly, if more than one lifetime is discovered in the self type, we
disregard it as a possible lifetime elision candidate.
This is a compatibility break, and in fact has required some changes to tests
which assumed the earlier behavior.
Fixes https://github.com/rust-lang/rust/issues/117715
Move `#[do_not_recommend]` to the `#[diagnostic]` namespace
This commit moves the `#[do_not_recommend]` attribute to the `#[diagnostic]` namespace. It still requires
`#![feature(do_not_recommend)]` to work.
r? `@compiler-errors`
Translation of the lint message happens when the actual diagnostic is
created, not when the lint is buffered. Generating the message from
BuiltinLintDiag ensures that all required data to construct the message
is preserved in the LintBuffer, eventually allowing the messages to be
moved to fluent.
Remove the `msg` field from BufferedEarlyLint, it is either generated
from the data in the BuiltinLintDiag or stored inside
BuiltinLintDiag::Normal.
Some minor (English only) heroics are performed to print error messages
like "5th rule of macro `m` is never used". The form "rule #5 of macro
`m` is never used" is just as good and much simpler to implement.
