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Regression in spacing of left margin in diagnostics #71363
Description
struct MyError;
impl std::error::Error for MyError {}$ cargo +nightly-2020-04-19 check
error[E0277]: `MyError` doesn't implement `std::fmt::Display`
--> src/main.rs:2:6
|
2 | impl std::error::Error for MyError {}
| ^^^^^^^^^^^^^^^^^ `MyError` cannot be formatted with the default formatter
|
= help: the trait `std::fmt::Display` is not implemented for `MyError`
= note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
$ cargo +nightly-2020-04-20 check
error[E0277]: `MyError` doesn't implement `std::fmt::Display`
--> src/main.rs:2:6
|
2 | impl std::error::Error for MyError {}
| ^^^^^^^^^^^^^^^^^ `MyError` cannot be formatted with the default formatter
|
= help: the trait `std::fmt::Display` is not implemented for `MyError`
= note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) insteadNotice the extra one column of indentation in front of the pipes. I presume this is unintentional because almost any other error is still printed without such extra indentation; for example:
error: expected one of `!`, `(`, `+`, `::`, `<`, `where`, or `{`, found `;`
--> src/main.rs:2:35
|
2 | impl std::error::Error for MyError;
| ^ expected one of 7 possible tokensThe relevant commit range is 52fa23a...dbf8b6b.
Mentioning @estebank @eddyb because #69745 looks like it touches error messages vaguely along the same lines.
Activity
Update ui tests to nightly-2020-04-20
estebank commentedon Apr 20, 2020
Could you show the output of
--message-format=json? The only thing I can think of is that there's aDUMMY_SPspan that isn't being displayed.dtolnay commentedon Apr 20, 2020
cargo +nightly-2020-04-20 check --message-format=json | jq{ "reason": "compiler-message", "package_id": "testing 0.0.0 (path+file:///git/testing)", "target": { "kind": [ "bin" ], "crate_types": [ "bin" ], "name": "testing", "src_path": "/git/testing/src/main.rs", "edition": "2018", "doctest": false }, "message": { "rendered": "error[E0277]: `MyError` doesn't implement `std::fmt::Display`\n --> src/main.rs:2:6\n |\n2 | impl std::error::Error for MyError {}\n | ^^^^^^^^^^^^^^^^^ `MyError` cannot be formatted with the default formatter\n |\n = help: the trait `std::fmt::Display` is not implemented for `MyError`\n = note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead\n\n", "children": [ { "children": [], "code": null, "level": "help", "message": "the trait `std::fmt::Display` is not implemented for `MyError`", "rendered": null, "spans": [] }, { "children": [], "code": null, "level": "note", "message": "in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead", "rendered": null, "spans": [] } ], "code": { "code": "E0277", "explanation": "You tried to use a type which doesn't implement some trait in a place which\nexpected that trait.\n\nErroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n foo.bar();\n}\n\nfn main() {\n // we now call the method with the i32 type, which doesn't implement\n // the Foo trait\n some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n foo.bar(); // we can now use this method since i32 implements the\n // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n fn bar(&self) {}\n}\n\nfn main() {\n some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n // implemented for the type `T`\n}\n\nfn main() {\n // We now call the method with the i32 type,\n // which *does* implement the Debug trait.\n some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n println!(\"{:?}\", foo);\n}\n\nfn main() {\n // Calling the method is still fine, as i32 implements Debug.\n some_func(5i32);\n\n // This would fail to compile now:\n // struct WithoutDebug;\n // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n" }, "level": "error", "message": "`MyError` doesn't implement `std::fmt::Display`", "spans": [ { "byte_end": 38, "byte_start": 21, "column_end": 23, "column_start": 6, "expansion": null, "file_name": "src/main.rs", "is_primary": true, "label": "`MyError` cannot be formatted with the default formatter", "line_end": 2, "line_start": 2, "suggested_replacement": null, "suggestion_applicability": null, "text": [ { "highlight_end": 23, "highlight_start": 6, "text": "impl std::error::Error for MyError {}" } ] }, { "byte_end": 1885, "byte_start": 1878, "column_end": 33, "column_start": 26, "expansion": null, "file_name": "/rustc/dbf8b6bf116c7bece2987ff4bd2792f008a6ee77/src/libstd/error.rs", "is_primary": false, "label": "required by this bound in `std::error::Error`", "line_end": 47, "line_start": 47, "suggested_replacement": null, "suggestion_applicability": null, "text": [] } ] } } { "reason": "compiler-message", "package_id": "testing 0.0.0 (path+file:///git/testing)", "target": { "kind": [ "bin" ], "crate_types": [ "bin" ], "name": "testing", "src_path": "/git/testing/src/main.rs", "edition": "2018", "doctest": false }, "message": { "rendered": "error[E0277]: `MyError` doesn't implement `std::fmt::Debug`\n --> src/main.rs:2:6\n |\n2 | impl std::error::Error for MyError {}\n | ^^^^^^^^^^^^^^^^^ `MyError` cannot be formatted using `{:?}`\n |\n = help: the trait `std::fmt::Debug` is not implemented for `MyError`\n = note: add `#[derive(Debug)]` or manually implement `std::fmt::Debug`\n\n", "children": [ { "children": [], "code": null, "level": "help", "message": "the trait `std::fmt::Debug` is not implemented for `MyError`", "rendered": null, "spans": [] }, { "children": [], "code": null, "level": "note", "message": "add `#[derive(Debug)]` or manually implement `std::fmt::Debug`", "rendered": null, "spans": [] } ], "code": { "code": "E0277", "explanation": "You tried to use a type which doesn't implement some trait in a place which\nexpected that trait.\n\nErroneous code example:\n\n```compile_fail,E0277\n// here we declare the Foo trait with a bar method\ntrait Foo {\n fn bar(&self);\n}\n\n// we now declare a function which takes an object implementing the Foo trait\nfn some_func<T: Foo>(foo: T) {\n foo.bar();\n}\n\nfn main() {\n // we now call the method with the i32 type, which doesn't implement\n // the Foo trait\n some_func(5i32); // error: the trait bound `i32 : Foo` is not satisfied\n}\n```\n\nIn order to fix this error, verify that the type you're using does implement\nthe trait. Example:\n\n```\ntrait Foo {\n fn bar(&self);\n}\n\nfn some_func<T: Foo>(foo: T) {\n foo.bar(); // we can now use this method since i32 implements the\n // Foo trait\n}\n\n// we implement the trait on the i32 type\nimpl Foo for i32 {\n fn bar(&self) {}\n}\n\nfn main() {\n some_func(5i32); // ok!\n}\n```\n\nOr in a generic context, an erroneous code example would look like:\n\n```compile_fail,E0277\nfn some_func<T>(foo: T) {\n println!(\"{:?}\", foo); // error: the trait `core::fmt::Debug` is not\n // implemented for the type `T`\n}\n\nfn main() {\n // We now call the method with the i32 type,\n // which *does* implement the Debug trait.\n some_func(5i32);\n}\n```\n\nNote that the error here is in the definition of the generic function: Although\nwe only call it with a parameter that does implement `Debug`, the compiler\nstill rejects the function: It must work with all possible input types. In\norder to make this example compile, we need to restrict the generic type we're\naccepting:\n\n```\nuse std::fmt;\n\n// Restrict the input type to types that implement Debug.\nfn some_func<T: fmt::Debug>(foo: T) {\n println!(\"{:?}\", foo);\n}\n\nfn main() {\n // Calling the method is still fine, as i32 implements Debug.\n some_func(5i32);\n\n // This would fail to compile now:\n // struct WithoutDebug;\n // some_func(WithoutDebug);\n}\n```\n\nRust only looks at the signature of the called function, as such it must\nalready specify all requirements that will be used for every type parameter.\n" }, "level": "error", "message": "`MyError` doesn't implement `std::fmt::Debug`", "spans": [ { "byte_end": 38, "byte_start": 21, "column_end": 23, "column_start": 6, "expansion": null, "file_name": "src/main.rs", "is_primary": true, "label": "`MyError` cannot be formatted using `{:?}`", "line_end": 2, "line_start": 2, "suggested_replacement": null, "suggestion_applicability": null, "text": [ { "highlight_end": 23, "highlight_start": 6, "text": "impl std::error::Error for MyError {}" } ] }, { "byte_end": 1875, "byte_start": 1870, "column_end": 23, "column_start": 18, "expansion": null, "file_name": "/rustc/dbf8b6bf116c7bece2987ff4bd2792f008a6ee77/src/libstd/error.rs", "is_primary": false, "label": "required by this bound in `std::error::Error`", "line_end": 47, "line_start": 47, "suggested_replacement": null, "suggestion_applicability": null, "text": [] } ] } }estebank commentedon Apr 20, 2020
I'm pretty sure it's happening because of this
It is weird because that file should be accessible to
rustcin all environments now. I think we can get away with some well placedif sp == DUMMY_SP { return; }in a few places.spastorino commentedon Apr 22, 2020
It maybe be nice if someone can find where this regressed ...
@rustbot ping cleanup
rustbot commentedon Apr 22, 2020
Hey Cleanup Crew ICE-breakers! This bug has been identified as a good
"Cleanup ICE-breaking candidate". In case it's useful, here are some
instructions for tackling these sorts of bugs. Maybe take a look?
Thanks! <3
cc @AminArria @chrissimpkins @contrun @DutchGhost @elshize @ethanboxx @h-michael @HallerPatrick @hdhoang @hellow554 @imtsuki @jakevossen5 @kanru @KarlK90 @LeSeulArtichaut @MAdrianMattocks @matheus-consoli @mental32 @nmccarty @Noah-Kennedy @pard68 @PeytonT @pierreN @Redblueflame @RobbieClarken @RobertoSnap @robjtede @SarthakSingh31 @senden9 @shekohex @sinato @spastorino @turboladen @woshilapin @yerke
spastorino commentedon Apr 22, 2020
Assigning
P-lowas discussed as part of the Prioritization Working Group process.chrissimpkins commentedon Apr 22, 2020
cargo bisect-rustc indicates that the regression is @ e7497a8 / PR #69793
cc @estebank
rossmacarthur commentedon Sep 26, 2021
@rustbot claim
Rollup merge of rust-lang#97504 - JohnTitor:cleanup-deps, r=davidtwco
fix rust-lang#71363 test by adding `-Z translate-remapped-path-to-loc…
Rollup merge of rust-lang#97789 - ferrocene:pa-fix-issue-71363-test, …
Rollup merge of rust-lang#97789 - ferrocene:pa-fix-issue-71363-test, …
Update ui tests to nightly-2020-04-20