compiler: Hint at multiple crate versions if trait impl is for wrong ADT #146874
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bors merged 2 commits intorust-lang:masterfrom Oct 6, 2025
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compiler: Hint at multiple crate versions if trait impl is for wrong ADT #146874bors merged 2 commits intorust-lang:masterfrom
bors merged 2 commits intorust-lang:masterfrom
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I haven't compared the two PRs but CC open PR #144674 which also touches this function. |
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Zalathar
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tests/run-make/crate-loading: Rename source files for clarity For rust-lang#146874 I originally tried to extend the existing test **tests/run-make/crate-loading**. That didn't work out since adding a re-export of the entire crate significantly changes the emitted error messsage. I did put some effort into making that test easier to understand however, by renaming its files. (Since I was confused myself at first.) Let's save some time for future devs by doing just the renames. Further cleanups are possible, but that will change the blessed output, so let's not do that right now. r? `@jieyouxu` since you have the context of rust-lang#146874
Kobzol
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Sep 23, 2025
tests/run-make/crate-loading: Rename source files for clarity For rust-lang#146874 I originally tried to extend the existing test **tests/run-make/crate-loading**. That didn't work out since adding a re-export of the entire crate significantly changes the emitted error messsage. I did put some effort into making that test easier to understand however, by renaming its files. (Since I was confused myself at first.) Let's save some time for future devs by doing just the renames. Further cleanups are possible, but that will change the blessed output, so let's not do that right now. r? ``@jieyouxu`` since you have the context of rust-lang#146874
matthiaskrgr
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Sep 23, 2025
tests/run-make/crate-loading: Rename source files for clarity For rust-lang#146874 I originally tried to extend the existing test **tests/run-make/crate-loading**. That didn't work out since adding a re-export of the entire crate significantly changes the emitted error messsage. I did put some effort into making that test easier to understand however, by renaming its files. (Since I was confused myself at first.) Let's save some time for future devs by doing just the renames. Further cleanups are possible, but that will change the blessed output, so let's not do that right now. r? ```@jieyouxu``` since you have the context of rust-lang#146874
rust-timer
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Rollup merge of #146875 - Enselic:better-file-names, r=jieyouxu tests/run-make/crate-loading: Rename source files for clarity For #146874 I originally tried to extend the existing test **tests/run-make/crate-loading**. That didn't work out since adding a re-export of the entire crate significantly changes the emitted error messsage. I did put some effort into making that test easier to understand however, by renaming its files. (Since I was confused myself at first.) Let's save some time for future devs by doing just the renames. Further cleanups are possible, but that will change the blessed output, so let's not do that right now. r? ```@jieyouxu``` since you have the context of #146874
Muscraft
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Sep 24, 2025
tests/run-make/crate-loading: Rename source files for clarity For rust-lang#146874 I originally tried to extend the existing test **tests/run-make/crate-loading**. That didn't work out since adding a re-export of the entire crate significantly changes the emitted error messsage. I did put some effort into making that test easier to understand however, by renaming its files. (Since I was confused myself at first.) Let's save some time for future devs by doing just the renames. Further cleanups are possible, but that will change the blessed output, so let's not do that right now. r? ```@jieyouxu``` since you have the context of rust-lang#146874
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…ieyouxu
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#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>
bors
added a commit
that referenced
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Oct 4, 2025
Rollup of 14 pull requests Successful merges: - #142670 (Document fully-qualified syntax in `as`' keyword doc) - #145685 (add CloneFromCell and Cell::get_cloned) - #146330 (Bump unicode_data and printables to version 17.0.0) - #146451 (Fix atan2 inaccuracy in documentation) - #146479 (add mem::conjure_zst) - #146874 (compiler: Hint at multiple crate versions if trait impl is for wrong ADT ) - #147117 (interpret `#[used]` as `#[used(compiler)]` on illumos) - #147190 (std: `sys::net` cleanups) - #147251 (Do not assert that a change in global cache only happens when concurrent) - #147280 (Return to needs-llvm-components being info-only) - #147288 (compiletest: Make `DirectiveLine` responsible for name/value splitting) - #147309 (Add documentation about unwinding to wasm targets) - #147315 (bless autodiff batching test) - #147323 (Fix top level ui tests check in tidy) r? `@ghost` `@rustbot` modify labels: rollup
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Oct 4, 2025
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@bors2 delegate=try |
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✌️ @Enselic, you can now perform try builds on this pull request! You can now post |
Zalathar
added a commit
to Zalathar/rust
that referenced
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Oct 5, 2025
…ieyouxu
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#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
Collaborator
bors
added a commit
that referenced
this pull request
Oct 5, 2025
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 #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
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💔 Test failed - checks-actions |
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Oh... you may need to normalize path separators too... I've been meaning to pull out shared normalization logic into |
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.
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@bors2 try |
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compiler: Hint at multiple crate versions if trait impl is for wrong ADT try-job: dist-various-1 try-job: aarch64-msvc-1
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@bors r+ rollup=iffy |
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rust-timer
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Rollup merge of #146874 - Enselic:multiple-adt-versions, r=jieyouxu 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 #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
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Rollup of 3 pull requests Successful merges: - rust-lang/rust#146027 (support link modifier `as-needed` for raw-dylib-elf) - rust-lang/rust#146874 (compiler: Hint at multiple crate versions if trait impl is for wrong ADT ) - rust-lang/rust#147237 ([rustdoc] Cleanup "highlight::end_expansion") r? `@ghost` `@rustbot` modify labels: rollup
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If a user does e.g.
and get a compilation error about that
From<Bar>is not implemented forFoo, check if multiple versions of the crate withFoois 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 #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.
Click to expand
Before fix
After fix
try-job: dist-various-1
try-job: aarch64-msvc-1