compiler: Hint at multiple crate versions if trait impl is for wrong ADT
If a user does e.g.
impl From<Bar> for foo::Foo
and get a compilation error about that `From<Bar>` is not implemented for `Foo`, check if multiple versions of the crate with `Foo` is present in the dependency graph. If so, give a hint about it.
Note that a test is added as a separate commit so it is easy to see what effect the fix has on the emitted error message.
This can be seen as a continuation of rust-lang/rust#124944.
I think this closes RUST-71693 but I haven't checked since it lacks a minimal reproducer. If this gets merged I'll ask that reporter if this fix works for them.
## Real world example
I encountered this case in the wild and didn't realize I had multiple versions of a crate in my dependency graph. So I was a bit confused at first. For reference, here is what that looked like.
<details>
<summary>Click to expand</summary>
### Before fix
```
error[E0277]: the trait bound `lambda_http::lambda_runtime::Diagnostic: From<Error>` is not satisfied
--> src/main.rs:73:5
|
73 | lambda_http::run(service_fn(handle_event)).await
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `From<Error>` is not implemented for `lambda_http::lambda_runtime::Diagnostic`
|
= help: the following other types implement trait `From<T>`:
`lambda_http::lambda_runtime::Diagnostic` implements `From<&str>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError + Send + Sync>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Infallible>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<lambda_runtime::deserializer::DeserializeError>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::io::Error>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::string::String>`
= note: required for `Error` to implement `Into<lambda_http::lambda_runtime::Diagnostic>`
note: required by a bound in `lambda_http::run`
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_http-0.17.0/src/lib.rs:199:26
|
194 | pub async fn run<'a, R, S, E>(handler: S) -> Result<(), Error>
| --- required by a bound in this function
...
199 | E: std::fmt::Debug + Into<Diagnostic>,
| ^^^^^^^^^^^^^^^^ required by this bound in `run`
error[E0277]: the trait bound `lambda_http::lambda_runtime::Diagnostic: From<Error>` is not satisfied
--> src/main.rs:73:48
|
73 | lambda_http::run(service_fn(handle_event)).await
| ^^^^^ the trait `From<Error>` is not implemented for `lambda_http::lambda_runtime::Diagnostic`
|
= help: the following other types implement trait `From<T>`:
`lambda_http::lambda_runtime::Diagnostic` implements `From<&str>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError + Send + Sync>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Infallible>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<lambda_runtime::deserializer::DeserializeError>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::io::Error>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::string::String>`
= note: required for `Error` to implement `Into<lambda_http::lambda_runtime::Diagnostic>`
note: required by a bound in `lambda_http::run`
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_http-0.17.0/src/lib.rs:199:26
|
194 | pub async fn run<'a, R, S, E>(handler: S) -> Result<(), Error>
| --- required by a bound in this function
...
199 | E: std::fmt::Debug + Into<Diagnostic>,
| ^^^^^^^^^^^^^^^^ required by this bound in `run`
For more information about this error, try `rustc --explain E0277`.
error: could not compile `auto-merge-dependabot-pull-requests-webhook` (bin "auto-merge-dependabot-pull-requests-webhook") due to 2 previous errors
```
### After fix
```
Compiling auto-merge-dependabot-pull-requests-webhook v0.1.0 (/home/martin/src/auto-merge-dependabot-prs/rust-webhook)
error[E0277]: the trait bound `lambda_http::lambda_runtime::Diagnostic: From<Error>` is not satisfied
--> src/main.rs:73:5
|
73 | lambda_http::run(service_fn(handle_event)).await
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `From<Error>` is not implemented for `lambda_http::lambda_runtime::Diagnostic`
|
help: item with same name found
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_runtime-0.13.0/src/diagnostic.rs:43:1
|
43 | pub struct Diagnostic {
| ^^^^^^^^^^^^^^^^^^^^^
= note: perhaps two different versions of crate `lambda_runtime` are being used?
= help: the following other types implement trait `From<T>`:
`lambda_http::lambda_runtime::Diagnostic` implements `From<&str>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError + Send + Sync>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Infallible>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<lambda_runtime::deserializer::DeserializeError>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::io::Error>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::string::String>`
= note: required for `Error` to implement `Into<lambda_http::lambda_runtime::Diagnostic>`
note: required by a bound in `lambda_http::run`
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_http-0.17.0/src/lib.rs:199:26
|
194 | pub async fn run<'a, R, S, E>(handler: S) -> Result<(), Error>
| --- required by a bound in this function
...
199 | E: std::fmt::Debug + Into<Diagnostic>,
| ^^^^^^^^^^^^^^^^ required by this bound in `run`
error[E0277]: the trait bound `lambda_http::lambda_runtime::Diagnostic: From<Error>` is not satisfied
--> src/main.rs:73:48
|
73 | lambda_http::run(service_fn(handle_event)).await
| ^^^^^ the trait `From<Error>` is not implemented for `lambda_http::lambda_runtime::Diagnostic`
|
help: item with same name found
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_runtime-0.13.0/src/diagnostic.rs:43:1
|
43 | pub struct Diagnostic {
| ^^^^^^^^^^^^^^^^^^^^^
= note: perhaps two different versions of crate `lambda_runtime` are being used?
= help: the following other types implement trait `From<T>`:
`lambda_http::lambda_runtime::Diagnostic` implements `From<&str>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError + Send + Sync>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Box<dyn StdError>>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<Infallible>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<lambda_runtime::deserializer::DeserializeError>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::io::Error>`
`lambda_http::lambda_runtime::Diagnostic` implements `From<std::string::String>`
= note: required for `Error` to implement `Into<lambda_http::lambda_runtime::Diagnostic>`
note: required by a bound in `lambda_http::run`
--> /home/martin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/lambda_http-0.17.0/src/lib.rs:199:26
|
194 | pub async fn run<'a, R, S, E>(handler: S) -> Result<(), Error>
| --- required by a bound in this function
...
199 | E: std::fmt::Debug + Into<Diagnostic>,
| ^^^^^^^^^^^^^^^^ required by this bound in `run`
For more information about this error, try `rustc --explain E0277`.
error: could not compile `auto-merge-dependabot-pull-requests-webhook` (bin "auto-merge-dependabot-pull-requests-webhook") due to 2 previous errors
```
</details>
try-job: dist-various-1
try-job: aarch64-msvc-1
If a user does e.g.
impl From<Bar> for foo::Foo
and get a compilation error about that `From<Bar>` is not implemented
for `Foo`, check if multiple versions of the crate with `Foo` is present
in the dependency graph. If so, give a hint about it.
I encountered this case in the wild and didn't realize I had multiple
versions of a crate in my dependency graph. So I was a bit confused at
first. This fix will make life easier for others.
Don’t suggest foreign `doc(hidden)` types in "the following other types implement trait" diagnostics
Fixes https://github.com/rust-lang/rust/issues/132024.
``@rustbot`` label A-diagnostics T-compiler
Clean up `ty::Dynamic`
1. As a follow-up to PR rust-lang/rust#143036, remove `DynKind` entirely.
2. Inside HIR ty lowering, consolidate modules `dyn_compatibility` and `lint` into `dyn_trait`
* `dyn_compatibility` wasn't about dyn compatibility itself, it's about lowering trait object types
* `lint` contained dyn-Trait-specific diagnostics+lints only
Make `AssocItem` aware of its impl kind
The general goal is to have fewer query dependencies by making `AssocItem` aware of its parent impl kind (inherent vs. trait) without having to query the parent def_kind.
See individual commits.
This reverts commit 1eeb8e8b151d1da7daa73837a25dc5f7a1a7fa28, reversing
changes made to 324bf2b9fd8bf9661e7045c8a93f5ff0ec1a8ca5.
Unfortunately the assert desugaring change is not backwards compatible,
see RUST-145770.
Code such as
```rust
#[derive(Debug)]
struct F {
data: bool
}
impl std::ops::Not for F {
type Output = bool;
fn not(self) -> Self::Output { !self.data }
}
fn main() {
let f = F { data: true };
assert!(f);
}
```
would be broken by the assert desugaring change. We may need to land
the change over an edition boundary, or limit the editions that the
desugaring change impacts.
rename erase_regions to erase_and_anonymize_regions
I find it consistently confusing that `erase_regions` does more than replacing regions with `'erased`. it also makes some code look real goofy to be writing manual folders to erase regions with a comment saying "we cant use erase regions" :> or code that re-calls erase_regions on types with regions already erased just to anonymize all the bound regions.
r? lcnr
idk how i feel about the name being almost twice as long now
Port limit attributes to the new attribute parsing infrastructure
Doesn't pass tests, to be rebased on https://github.com/rust-lang/rust/pull/145792 which will solve that
r? `@fmease`
Suggest bounds in more cases, accounting for type parameters referenced in predicate
Use a `ty::Visitor` to see if the failed predicate references a type parameter. If it does, then we only suggest adding a bound to an (associated) item only if the referenced parameter is present in its generics.
Provide adding bound suggestion in trait and impl associated functions in cases we previously weren't:
```
error[E0277]: `?` couldn't convert the error to `ApplicationError`
--> $DIR/suggest-complex-bound-on-method.rs:18:16
|
LL | t.run()?;
| -----^ the trait `From<<T as Trait>::Error>` is not implemented for `ApplicationError`
| |
| this can't be annotated with `?` because it has type `Result<_, <T as Trait>::Error>`
|
note: `ApplicationError` needs to implement `From<<T as Trait>::Error>`
--> $DIR/suggest-complex-bound-on-method.rs:12:1
|
LL | enum ApplicationError {
| ^^^^^^^^^^^^^^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
|
LL | fn thing<T: Trait>(&self, t: T) -> Result<(), ApplicationError> where ApplicationError: From<<T as Trait>::Error> {
| +++++++++++++++++++++++++++++++++++++++++++++++++
```
Fixrust-lang/rust#144734.
```
error[E0277]: the trait bound `usize: Neg` is not satisfied
--> $DIR/negative-literal-infered-to-unsigned.rs:2:14
|
LL | for x in -5..5 {
| ^^ the trait `Neg` is not implemented for `usize`
|
help: consider specifying an integer type that can be negative
|
LL | for x in -5isize..5 {
| +++++
```
On E0277, point at type that doesn't implement bound
When encountering an unmet trait bound, point at local type that doesn't implement the trait:
```
error[E0277]: the trait bound `Bar<T>: Foo` is not satisfied
--> $DIR/issue-64855.rs:9:19
|
LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ;
| ^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound
|
help: the trait `Foo` is not implemented for `Bar<T>`
--> $DIR/issue-64855.rs:9:1
|
LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ;
| ^^^^^^^^^^^^^^^^^
```
When encountering an unmet trait bound, point at local type that doesn't implement the trait:
```
error[E0277]: the trait bound `Bar<T>: Foo` is not satisfied
--> $DIR/issue-64855.rs:9:19
|
LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ;
| ^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound
|
help: the trait `Foo` is not implemented for `Bar<T>`
--> $DIR/issue-64855.rs:9:1
|
LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ;
| ^^^^^^^^^^^^^^^^^
```
Print regions in `type_name`.
Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`.
Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo.
`c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter.
The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions.
Fixesrust-lang/rust#145168.
r? `@lcnr`
Change the desugaring of `assert!` for better error output
In the desugaring of `assert!`, we now expand to a `match` expression instead of `if !cond {..}`.
The span of incorrect conditions will point only at the expression, and not the whole `assert!` invocation.
```
error[E0308]: mismatched types
--> $DIR/issue-14091.rs:2:13
|
LL | assert!(1,1);
| ^ expected `bool`, found integer
```
We no longer mention the expression needing to implement the `Not` trait.
```
error[E0308]: mismatched types
--> $DIR/issue-14091-2.rs:15:13
|
LL | assert!(x, x);
| ^ expected `bool`, found `BytePos`
```
Now `assert!(val)` desugars to:
```rust
match val {
true => {},
_ => $crate::panic::panic_2021!(),
}
```
Fix#122159.
Currently they are skipped, which is a bit weird, and it sometimes
causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`.
Most regions are erased by the time `type_name` does its work. So all
regions are now printed as `'_` in non-optional places. Not perfect, but
better than the status quo.
`c_name` is updated to trim lifetimes from MIR pass names, so that the
`PASS_NAMES` sanity check still works. It is also renamed as
`simplify_pass_type_name` and made non-const, because it doesn't need
to be const and the non-const implementation is much shorter.
The commit also renames `should_print_region` as
`should_print_optional_region`, which makes it clearer that it only
applies to some regions.
Fixes#145168.
In the desugaring of `assert!`, we now expand to a `match` expression
instead of `if !cond {..}`.
The span of incorrect conditions will point only at the expression, and not
the whole `assert!` invocation.
```
error[E0308]: mismatched types
--> $DIR/issue-14091.rs:2:13
|
LL | assert!(1,1);
| ^ expected `bool`, found integer
```
We no longer mention the expression needing to implement the `Not` trait.
```
error[E0308]: mismatched types
--> $DIR/issue-14091-2.rs:15:13
|
LL | assert!(x, x);
| ^ expected `bool`, found `BytePos`
```
`assert!(val)` now desugars to:
```rust
match val {
true => {},
_ => $crate::panic::panic_2021!(),
}
```
Fix#122159.
We make some minor changes to some diagnostics to avoid span overlap on
type mismatch or inverted "expected"/"found" on type errors.
We remove some unnecessary parens from core, alloc and miri.
address review comments
`TyCtxt::short_string` ensures that user visible type paths aren't overwhelming on the terminal output, and properly saves the long name to disk as a side-channel. We already use these throughout the compiler and have been using them as needed when users find cases where the output is verbose. This is a proactive search of some cases to use `short_string`.
We add support for shortening the path of "trait path only".
Every manual use of `short_string` is a bright marker that that error should be using structured diagnostics instead (as they have proper handling of long types without the maintainer having to think abou tthem).
When we don't actually print out a shortened type we don't need the "use `--verbose`" note.
On E0599 show type identity to avoid expanding the receiver's generic parameters.
Unify wording on `long_ty_path` everywhere.
Three of them are named `AbsolutePathPrinter`, which is confusing, so
give those names that better indicate how they are used. And then there
is `SymbolPrinter` and `SymbolMangler`, which are renamed as
`LegacySymbolMangler` and `V0SymbolMangler`, better indicating their
similarity.
