diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs index d0eb1cfc222..988ec3d4374 100644 --- a/src/librustc_resolve/build_reduced_graph.rs +++ b/src/librustc_resolve/build_reduced_graph.rs @@ -426,7 +426,7 @@ fn build_reduced_graph_for_use_tree( return; } - // Replace `use foo::self;` with `use foo;` + // Replace `use foo::{ self };` with `use foo;` source = module_path.pop().unwrap(); if rename.is_none() { ident = source.ident; @@ -435,10 +435,33 @@ fn build_reduced_graph_for_use_tree( } else { // Disallow `self` if source.ident.name == kw::SelfLower { + let parent = module_path.last(); + + let span = match parent { + // only `::self` from `use foo::self as bar` + Some(seg) => seg.ident.span.shrink_to_hi().to(source.ident.span), + None => source.ident.span, + }; + let span_with_rename = match rename { + // only `self as bar` from `use foo::self as bar` + Some(rename) => source.ident.span.to(rename.span), + None => source.ident.span, + }; self.r.report_error( - use_tree.span, - ResolutionError::SelfImportsOnlyAllowedWithin, + span, + ResolutionError::SelfImportsOnlyAllowedWithin { + root: parent.is_none(), + span_with_rename, + }, ); + + // Error recovery: replace `use foo::self;` with `use foo;` + if let Some(parent) = module_path.pop() { + source = parent; + if rename.is_none() { + ident = source.ident; + } + } } // Disallow `use $crate;` diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs index c66e9a60406..ea237f1a04f 100644 --- a/src/librustc_resolve/diagnostics.rs +++ b/src/librustc_resolve/diagnostics.rs @@ -301,13 +301,40 @@ impl<'a> Resolver<'a> { } err } - ResolutionError::SelfImportsOnlyAllowedWithin => struct_span_err!( - self.session, - span, - E0429, - "{}", - "`self` imports are only allowed within a { } list" - ), + ResolutionError::SelfImportsOnlyAllowedWithin { root, span_with_rename } => { + let mut err = struct_span_err!( + self.session, + span, + E0429, + "{}", + "`self` imports are only allowed within a { } list" + ); + + // None of the suggestions below would help with a case like `use self`. + if !root { + // use foo::bar::self -> foo::bar + // use foo::bar::self as abc -> foo::bar as abc + err.span_suggestion( + span, + "consider importing the module directly", + "".to_string(), + Applicability::MachineApplicable, + ); + + // use foo::bar::self -> foo::bar::{self} + // use foo::bar::self as abc -> foo::bar::{self as abc} + let braces = vec![ + (span_with_rename.shrink_to_lo(), "{".to_string()), + (span_with_rename.shrink_to_hi(), "}".to_string()), + ]; + err.multipart_suggestion( + "alternatively, use the multi-path `use` syntax to import `self`", + braces, + Applicability::MachineApplicable, + ); + } + err + } ResolutionError::SelfImportCanOnlyAppearOnceInTheList => { let mut err = struct_span_err!( self.session, diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index 2031b7868c0..bfb7f081fc3 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -194,7 +194,7 @@ enum ResolutionError<'a> { /// Error E0426: use of undeclared label. UndeclaredLabel(&'a str, Option), /// Error E0429: `self` imports are only allowed within a `{ }` list. - SelfImportsOnlyAllowedWithin, + SelfImportsOnlyAllowedWithin { root: bool, span_with_rename: Span }, /// Error E0430: `self` import can only appear once in the list. SelfImportCanOnlyAppearOnceInTheList, /// Error E0431: `self` import can only appear in an import list with a non-empty prefix. diff --git a/src/test/ui/error-codes/E0429.stderr b/src/test/ui/error-codes/E0429.stderr index b5f76a1fcd8..c598803fa6c 100644 --- a/src/test/ui/error-codes/E0429.stderr +++ b/src/test/ui/error-codes/E0429.stderr @@ -1,8 +1,17 @@ error[E0429]: `self` imports are only allowed within a { } list - --> $DIR/E0429.rs:1:5 + --> $DIR/E0429.rs:1:13 | LL | use std::fmt::self; - | ^^^^^^^^^^^^^^ + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use std::fmt; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use std::fmt::{self}; + | ^ ^ error: aborting due to previous error diff --git a/src/test/ui/issues/issue-45829/import-self.rs b/src/test/ui/issues/issue-45829/import-self.rs index 6cb18e1cdb7..2dc4331ced7 100644 --- a/src/test/ui/issues/issue-45829/import-self.rs +++ b/src/test/ui/issues/issue-45829/import-self.rs @@ -9,7 +9,7 @@ mod foo { use foo as self; //~^ ERROR expected identifier -use foo::self; +use foo::self; //~ ERROR is defined multiple times //~^ ERROR `self` imports are only allowed within a { } list use foo::A; diff --git a/src/test/ui/issues/issue-45829/import-self.stderr b/src/test/ui/issues/issue-45829/import-self.stderr index 39522cd8183..158e81cdd96 100644 --- a/src/test/ui/issues/issue-45829/import-self.stderr +++ b/src/test/ui/issues/issue-45829/import-self.stderr @@ -5,10 +5,19 @@ LL | use foo as self; | ^^^^ expected identifier, found keyword error[E0429]: `self` imports are only allowed within a { } list - --> $DIR/import-self.rs:12:5 + --> $DIR/import-self.rs:12:8 | LL | use foo::self; - | ^^^^^^^^^ + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use foo; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use foo::{self}; + | ^ ^ error[E0255]: the name `foo` is defined multiple times --> $DIR/import-self.rs:6:11 @@ -25,6 +34,21 @@ help: you can use `as` to change the binding name of the import LL | use foo::{self as other_foo}; | ^^^^^^^^^^^^^^^^^ +error[E0255]: the name `foo` is defined multiple times + --> $DIR/import-self.rs:12:5 + | +LL | mod foo { + | ------- previous definition of the module `foo` here +... +LL | use foo::self; + | ^^^^^^^^^ `foo` reimported here + | + = note: `foo` must be defined only once in the type namespace of this module +help: you can use `as` to change the binding name of the import + | +LL | use foo as other_foo; + | ^^^^^^^^^^^^^^^^ + error[E0252]: the name `A` is defined multiple times --> $DIR/import-self.rs:16:11 | @@ -39,7 +63,7 @@ help: you can use `as` to change the binding name of the import LL | use foo::{self as OtherA}; | ^^^^^^^^^^^^^^ -error: aborting due to 4 previous errors +error: aborting due to 5 previous errors Some errors have detailed explanations: E0252, E0255, E0429. For more information about an error, try `rustc --explain E0252`. diff --git a/src/test/ui/use/use-keyword.stderr b/src/test/ui/use/use-keyword.stderr index 62b6a77fbfb..501d14be521 100644 --- a/src/test/ui/use/use-keyword.stderr +++ b/src/test/ui/use/use-keyword.stderr @@ -2,7 +2,7 @@ error[E0429]: `self` imports are only allowed within a { } list --> $DIR/use-keyword.rs:6:13 | LL | use self as A; - | ^^^^^^^^^ + | ^^^^ error[E0432]: unresolved import `super` --> $DIR/use-keyword.rs:8:13 diff --git a/src/test/ui/use/use-mod/use-mod-4.stderr b/src/test/ui/use/use-mod/use-mod-4.stderr index e30e5c3ceb1..a29bd07ac44 100644 --- a/src/test/ui/use/use-mod/use-mod-4.stderr +++ b/src/test/ui/use/use-mod/use-mod-4.stderr @@ -1,20 +1,38 @@ error[E0429]: `self` imports are only allowed within a { } list - --> $DIR/use-mod-4.rs:1:5 + --> $DIR/use-mod-4.rs:1:8 | LL | use foo::self; - | ^^^^^^^^^ + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use foo; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use foo::{self}; + | ^ ^ error[E0429]: `self` imports are only allowed within a { } list - --> $DIR/use-mod-4.rs:4:5 + --> $DIR/use-mod-4.rs:4:13 | LL | use std::mem::self; - | ^^^^^^^^^^^^^^ + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use std::mem; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use std::mem::{self}; + | ^ ^ error[E0432]: unresolved import `foo` --> $DIR/use-mod-4.rs:1:5 | LL | use foo::self; - | ^^^ maybe a missing crate `foo`? + | ^^^^^^^^^ no `foo` in the root error: aborting due to 3 previous errors diff --git a/src/test/ui/use/use-mod/use-mod-5.rs b/src/test/ui/use/use-mod/use-mod-5.rs new file mode 100644 index 00000000000..df5b423ec57 --- /dev/null +++ b/src/test/ui/use/use-mod/use-mod-5.rs @@ -0,0 +1,13 @@ +mod foo { + pub mod bar { + pub fn drop() {} + } +} + +use foo::bar::self; +//~^ ERROR `self` imports are only allowed within a { } list + +fn main() { + // Because of error recovery this shouldn't error + bar::drop(); +} diff --git a/src/test/ui/use/use-mod/use-mod-5.stderr b/src/test/ui/use/use-mod/use-mod-5.stderr new file mode 100644 index 00000000000..ebb71c51293 --- /dev/null +++ b/src/test/ui/use/use-mod/use-mod-5.stderr @@ -0,0 +1,18 @@ +error[E0429]: `self` imports are only allowed within a { } list + --> $DIR/use-mod-5.rs:7:13 + | +LL | use foo::bar::self; + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use foo::bar; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use foo::bar::{self}; + | ^ ^ + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0429`. diff --git a/src/test/ui/use/use-mod/use-mod-6.rs b/src/test/ui/use/use-mod/use-mod-6.rs new file mode 100644 index 00000000000..1f8777daca4 --- /dev/null +++ b/src/test/ui/use/use-mod/use-mod-6.rs @@ -0,0 +1,13 @@ +mod foo { + pub mod bar { + pub fn drop() {} + } +} + +use foo::bar::self as abc; +//~^ ERROR `self` imports are only allowed within a { } list + +fn main() { + // Because of error recovery this shouldn't error + abc::drop(); +} diff --git a/src/test/ui/use/use-mod/use-mod-6.stderr b/src/test/ui/use/use-mod/use-mod-6.stderr new file mode 100644 index 00000000000..36fdf9c75c7 --- /dev/null +++ b/src/test/ui/use/use-mod/use-mod-6.stderr @@ -0,0 +1,18 @@ +error[E0429]: `self` imports are only allowed within a { } list + --> $DIR/use-mod-6.rs:7:13 + | +LL | use foo::bar::self as abc; + | ^^^^^^ + | +help: consider importing the module directly + | +LL | use foo::bar as abc; + | -- +help: alternatively, use the multi-path `use` syntax to import `self` + | +LL | use foo::bar::{self as abc}; + | ^ ^ + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0429`.