From 0fb4ef6769dd2f5ccb3daf1e84c0afe75ca8c118 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Le=C3=B3n=20Orell=20Valerian=20Liehr?= Date: Wed, 10 Aug 2022 14:06:27 +0200 Subject: [PATCH] Suggest path separator when a dot is used on a trait --- .../rustc_resolve/src/late/diagnostics.rs | 53 ++++++++---- src/test/ui/resolve/issue-100365.rs | 50 +++++++++++ src/test/ui/resolve/issue-100365.stderr | 54 ++++++++++++ src/test/ui/resolve/issue-22692.rs | 59 ++++++++++++- src/test/ui/resolve/issue-22692.stderr | 85 ++++++++++++++++++- .../suggest-path-for-tuple-struct.stderr | 8 +- .../suggest-path-instead-of-mod-dot-item.rs | 52 ++++++++++++ ...uggest-path-instead-of-mod-dot-item.stderr | 82 +++++++++++++----- .../suggestions/assoc-const-as-field.stderr | 4 +- 9 files changed, 394 insertions(+), 53 deletions(-) create mode 100644 src/test/ui/resolve/issue-100365.rs create mode 100644 src/test/ui/resolve/issue-100365.stderr diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs index cb133841bca..09c1f44826f 100644 --- a/compiler/rustc_resolve/src/late/diagnostics.rs +++ b/compiler/rustc_resolve/src/late/diagnostics.rs @@ -985,27 +985,45 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { let ns = source.namespace(); let is_expected = &|res| source.is_expected(res); - let path_sep = |err: &mut Diagnostic, expr: &Expr| match expr.kind { - ExprKind::Field(_, ident) => { + let path_sep = |err: &mut Diagnostic, expr: &Expr, kind: DefKind| { + const MESSAGE: &str = "use the path separator to refer to an item"; + + let (lhs_span, rhs_span) = match &expr.kind { + ExprKind::Field(base, ident) => (base.span, ident.span), + ExprKind::MethodCall(_, receiver, _, span) => (receiver.span, *span), + _ => return false, + }; + + if lhs_span.eq_ctxt(rhs_span) { err.span_suggestion( - expr.span, - "use the path separator to refer to an item", - format!("{}::{}", path_str, ident), + lhs_span.between(rhs_span), + MESSAGE, + "::", Applicability::MaybeIncorrect, ); true - } - ExprKind::MethodCall(ref segment, ..) => { - let span = expr.span.with_hi(segment.ident.span.hi()); - err.span_suggestion( - span, - "use the path separator to refer to an item", - format!("{}::{}", path_str, segment.ident), + } else if kind == DefKind::Struct + && let Some(lhs_source_span) = lhs_span.find_ancestor_inside(expr.span) + && let Ok(snippet) = self.r.session.source_map().span_to_snippet(lhs_source_span) + { + // The LHS is a type that originates from a macro call. + // We have to add angle brackets around it. + + err.span_suggestion_verbose( + lhs_source_span.until(rhs_span), + MESSAGE, + format!("<{snippet}>::"), Applicability::MaybeIncorrect, ); true + } else { + // Either we were unable to obtain the source span / the snippet or + // the LHS originates from a macro call and it is not a type and thus + // there is no way to replace `.` with `::` and still somehow suggest + // valid Rust code. + + false } - _ => false, }; let find_span = |source: &PathSource<'_>, err: &mut Diagnostic| { @@ -1027,7 +1045,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { match source { PathSource::Expr(Some( parent @ Expr { kind: ExprKind::Field(..) | ExprKind::MethodCall(..), .. }, - )) if path_sep(err, &parent) => {} + )) if path_sep(err, &parent, DefKind::Struct) => {} PathSource::Expr( None | Some(Expr { @@ -1143,8 +1161,11 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { } } } - (Res::Def(DefKind::Mod, _), PathSource::Expr(Some(parent))) => { - if !path_sep(err, &parent) { + ( + Res::Def(kind @ (DefKind::Mod | DefKind::Trait), _), + PathSource::Expr(Some(parent)), + ) => { + if !path_sep(err, &parent, kind) { return false; } } diff --git a/src/test/ui/resolve/issue-100365.rs b/src/test/ui/resolve/issue-100365.rs new file mode 100644 index 00000000000..1d883503606 --- /dev/null +++ b/src/test/ui/resolve/issue-100365.rs @@ -0,0 +1,50 @@ +fn main() { + let addr = Into::.into([127, 0, 0, 1]); + //~^ ERROR expected value, found trait `Into` + //~| HELP use the path separator + + let _ = Into.into(()); + //~^ ERROR expected value, found trait `Into` + //~| HELP use the path separator + + let _ = Into::<()>.into; + //~^ ERROR expected value, found trait `Into` + //~| HELP use the path separator +} + +macro_rules! Trait { + () => { + ::std::iter::Iterator + //~^ ERROR expected value, found trait `std::iter::Iterator` + //~| ERROR expected value, found trait `std::iter::Iterator` + }; +} + +macro_rules! create { + () => { + Into::.into("") + //~^ ERROR expected value, found trait `Into` + //~| HELP use the path separator + }; +} + +fn interaction_with_macros() { + // + // Note that if the receiver is a macro call, we do not want to suggest to replace + // `.` with `::` as that would be a syntax error. + // Since the receiver is a trait and not a type, we cannot suggest to surround + // it with angle brackets. It would be interpreted as a trait object type void of + // `dyn` which is most likely not what the user intended to write. + // `<_ as Trait!()>::` is also not an option as it's equally syntactically invalid. + // + + Trait!().map(std::convert::identity); // no `help` here! + + Trait!().map; // no `help` here! + + // + // Ensure that the suggestion is shown for expressions inside of macro definitions. + // + + let _ = create!(); +} diff --git a/src/test/ui/resolve/issue-100365.stderr b/src/test/ui/resolve/issue-100365.stderr new file mode 100644 index 00000000000..372d7726668 --- /dev/null +++ b/src/test/ui/resolve/issue-100365.stderr @@ -0,0 +1,54 @@ +error[E0423]: expected value, found trait `Into` + --> $DIR/issue-100365.rs:2:16 + | +LL | let addr = Into::.into([127, 0, 0, 1]); + | ^^^^^^^^^^^^^^^^^^^^^^^^- help: use the path separator to refer to an item: `::` + +error[E0423]: expected value, found trait `Into` + --> $DIR/issue-100365.rs:6:13 + | +LL | let _ = Into.into(()); + | ^^^^- help: use the path separator to refer to an item: `::` + +error[E0423]: expected value, found trait `Into` + --> $DIR/issue-100365.rs:10:13 + | +LL | let _ = Into::<()>.into; + | ^^^^^^^^^^- help: use the path separator to refer to an item: `::` + +error[E0423]: expected value, found trait `std::iter::Iterator` + --> $DIR/issue-100365.rs:17:9 + | +LL | ::std::iter::Iterator + | ^^^^^^^^^^^^^^^^^^^^^ not a value +... +LL | Trait!().map(std::convert::identity); // no `help` here! + | -------- in this macro invocation + | + = note: this error originates in the macro `Trait` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found trait `std::iter::Iterator` + --> $DIR/issue-100365.rs:17:9 + | +LL | ::std::iter::Iterator + | ^^^^^^^^^^^^^^^^^^^^^ not a value +... +LL | Trait!().map; // no `help` here! + | -------- in this macro invocation + | + = note: this error originates in the macro `Trait` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found trait `Into` + --> $DIR/issue-100365.rs:25:9 + | +LL | Into::.into("") + | ^^^^^^^^^^^^^^- help: use the path separator to refer to an item: `::` +... +LL | let _ = create!(); + | --------- in this macro invocation + | + = note: this error originates in the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) + +error: aborting due to 6 previous errors + +For more information about this error, try `rustc --explain E0423`. diff --git a/src/test/ui/resolve/issue-22692.rs b/src/test/ui/resolve/issue-22692.rs index 1d8f442221d..31a76261408 100644 --- a/src/test/ui/resolve/issue-22692.rs +++ b/src/test/ui/resolve/issue-22692.rs @@ -1,3 +1,60 @@ fn main() { - let _ = String.new(); //~ ERROR expected value, found struct `String` + let _ = String.new(); + //~^ ERROR expected value, found struct `String` + //~| HELP use the path separator + + let _ = String.default; + //~^ ERROR expected value, found struct `String` + //~| HELP use the path separator + + let _ = Vec::<()>.with_capacity(1); + //~^ ERROR expected value, found struct `Vec` + //~| HELP use the path separator +} + +macro_rules! Type { + () => { + ::std::cell::Cell + //~^ ERROR expected value, found struct `std::cell::Cell` + //~| ERROR expected value, found struct `std::cell::Cell` + //~| ERROR expected value, found struct `std::cell::Cell` + }; +} + +macro_rules! create { + (type method) => { + Vec.new() + //~^ ERROR expected value, found struct `Vec` + //~| HELP use the path separator + }; + (type field) => { + Vec.new + //~^ ERROR expected value, found struct `Vec` + //~| HELP use the path separator + }; + (macro method) => { + Type!().new(0) + //~^ HELP use the path separator + }; +} + +fn interaction_with_macros() { + // + // Verify that we do not only suggest to replace `.` with `::` if the receiver is a + // macro call but that we also correctly suggest to surround it with angle brackets. + // + + Type!().get(); + //~^ HELP use the path separator + + Type! {}.get; + //~^ HELP use the path separator + + // + // Ensure that the suggestion is shown for expressions inside of macro definitions. + // + + let _ = create!(type method); + let _ = create!(type field); + let _ = create!(macro method); } diff --git a/src/test/ui/resolve/issue-22692.stderr b/src/test/ui/resolve/issue-22692.stderr index e076419f68d..6962aa161e9 100644 --- a/src/test/ui/resolve/issue-22692.stderr +++ b/src/test/ui/resolve/issue-22692.stderr @@ -2,10 +2,87 @@ error[E0423]: expected value, found struct `String` --> $DIR/issue-22692.rs:2:13 | LL | let _ = String.new(); - | ^^^^^^---- - | | - | help: use the path separator to refer to an item: `String::new` + | ^^^^^^- help: use the path separator to refer to an item: `::` -error: aborting due to previous error +error[E0423]: expected value, found struct `String` + --> $DIR/issue-22692.rs:6:13 + | +LL | let _ = String.default; + | ^^^^^^- help: use the path separator to refer to an item: `::` + +error[E0423]: expected value, found struct `Vec` + --> $DIR/issue-22692.rs:10:13 + | +LL | let _ = Vec::<()>.with_capacity(1); + | ^^^^^^^^^- help: use the path separator to refer to an item: `::` + +error[E0423]: expected value, found struct `std::cell::Cell` + --> $DIR/issue-22692.rs:17:9 + | +LL | ::std::cell::Cell + | ^^^^^^^^^^^^^^^^^ +... +LL | Type!().get(); + | ------- in this macro invocation + | + = note: this error originates in the macro `Type` (in Nightly builds, run with -Z macro-backtrace for more info) +help: use the path separator to refer to an item + | +LL | ::get(); + | ~~~~~~~~~~~ + +error[E0423]: expected value, found struct `std::cell::Cell` + --> $DIR/issue-22692.rs:17:9 + | +LL | ::std::cell::Cell + | ^^^^^^^^^^^^^^^^^ +... +LL | Type! {}.get; + | -------- in this macro invocation + | + = note: this error originates in the macro `Type` (in Nightly builds, run with -Z macro-backtrace for more info) +help: use the path separator to refer to an item + | +LL | ::get; + | ~~~~~~~~~~~~ + +error[E0423]: expected value, found struct `Vec` + --> $DIR/issue-22692.rs:26:9 + | +LL | Vec.new() + | ^^^- help: use the path separator to refer to an item: `::` +... +LL | let _ = create!(type method); + | -------------------- in this macro invocation + | + = note: this error originates in the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found struct `Vec` + --> $DIR/issue-22692.rs:31:9 + | +LL | Vec.new + | ^^^- help: use the path separator to refer to an item: `::` +... +LL | let _ = create!(type field); + | ------------------- in this macro invocation + | + = note: this error originates in the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found struct `std::cell::Cell` + --> $DIR/issue-22692.rs:17:9 + | +LL | ::std::cell::Cell + | ^^^^^^^^^^^^^^^^^ +... +LL | let _ = create!(macro method); + | --------------------- in this macro invocation + | + = note: this error originates in the macro `Type` which comes from the expansion of the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) +help: use the path separator to refer to an item + | +LL | ::new(0) + | ~~~~~~~~~~~ + +error: aborting due to 8 previous errors For more information about this error, try `rustc --explain E0423`. diff --git a/src/test/ui/resolve/suggest-path-for-tuple-struct.stderr b/src/test/ui/resolve/suggest-path-for-tuple-struct.stderr index 957045ca74b..4764cf2db20 100644 --- a/src/test/ui/resolve/suggest-path-for-tuple-struct.stderr +++ b/src/test/ui/resolve/suggest-path-for-tuple-struct.stderr @@ -2,17 +2,13 @@ error[E0423]: expected value, found struct `SomeTupleStruct` --> $DIR/suggest-path-for-tuple-struct.rs:22:13 | LL | let _ = SomeTupleStruct.new(); - | ^^^^^^^^^^^^^^^---- - | | - | help: use the path separator to refer to an item: `SomeTupleStruct::new` + | ^^^^^^^^^^^^^^^- help: use the path separator to refer to an item: `::` error[E0423]: expected value, found struct `SomeRegularStruct` --> $DIR/suggest-path-for-tuple-struct.rs:24:13 | LL | let _ = SomeRegularStruct.new(); - | ^^^^^^^^^^^^^^^^^---- - | | - | help: use the path separator to refer to an item: `SomeRegularStruct::new` + | ^^^^^^^^^^^^^^^^^- help: use the path separator to refer to an item: `::` error: aborting due to 2 previous errors diff --git a/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.rs b/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.rs index 204a272402d..d5d6b13d62c 100644 --- a/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.rs +++ b/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.rs @@ -16,44 +16,96 @@ pub mod a { fn h1() -> i32 { a.I //~^ ERROR expected value, found module `a` + //~| HELP use the path separator } fn h2() -> i32 { a.g() //~^ ERROR expected value, found module `a` + //~| HELP use the path separator } fn h3() -> i32 { a.b.J //~^ ERROR expected value, found module `a` + //~| HELP use the path separator } fn h4() -> i32 { a::b.J //~^ ERROR expected value, found module `a::b` + //~| HELP a constant with a similar name exists + //~| HELP use the path separator } fn h5() { a.b.f(); //~^ ERROR expected value, found module `a` + //~| HELP use the path separator let v = Vec::new(); v.push(a::b); //~^ ERROR expected value, found module `a::b` + //~| HELP a constant with a similar name exists } fn h6() -> i32 { a::b.f() //~^ ERROR expected value, found module `a::b` + //~| HELP a constant with a similar name exists + //~| HELP use the path separator } fn h7() { a::b //~^ ERROR expected value, found module `a::b` + //~| HELP a constant with a similar name exists } fn h8() -> i32 { a::b() //~^ ERROR expected function, found module `a::b` + //~| HELP a constant with a similar name exists +} + +macro_rules! module { + () => { + a + //~^ ERROR expected value, found module `a` + //~| ERROR expected value, found module `a` + }; +} + +macro_rules! create { + (method) => { + a.f() + //~^ ERROR expected value, found module `a` + //~| HELP use the path separator + }; + (field) => { + a.f + //~^ ERROR expected value, found module `a` + //~| HELP use the path separator + }; +} + +fn h9() { + // + // Note that if the receiver is a macro call, we do not want to suggest to replace + // `.` with `::` as that would be a syntax error. + // Since the receiver is a module and not a type, we cannot suggest to surround + // it with angle brackets. + // + + module!().g::<()>(); // no `help` here! + + module!().g; // no `help` here! + + // + // Ensure that the suggestion is shown for expressions inside of macro definitions. + // + + let _ = create!(method); + let _ = create!(field); } fn main() {} diff --git a/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.stderr b/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.stderr index 54b242123eb..a4ce0deeb70 100644 --- a/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.stderr +++ b/src/test/ui/resolve/suggest-path-instead-of-mod-dot-item.stderr @@ -2,28 +2,22 @@ error[E0423]: expected value, found module `a` --> $DIR/suggest-path-instead-of-mod-dot-item.rs:17:5 | LL | a.I - | ^-- - | | - | help: use the path separator to refer to an item: `a::I` + | ^- help: use the path separator to refer to an item: `::` error[E0423]: expected value, found module `a` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:22:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:23:5 | LL | a.g() - | ^-- - | | - | help: use the path separator to refer to an item: `a::g` + | ^- help: use the path separator to refer to an item: `::` error[E0423]: expected value, found module `a` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:27:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:29:5 | LL | a.b.J - | ^-- - | | - | help: use the path separator to refer to an item: `a::b` + | ^- help: use the path separator to refer to an item: `::` error[E0423]: expected value, found module `a::b` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:32:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:35:5 | LL | pub const I: i32 = 1; | --------------------- similarly named constant `I` defined here @@ -34,22 +28,20 @@ LL | a::b.J help: use the path separator to refer to an item | LL | a::b::J - | + | ~~ help: a constant with a similar name exists | LL | a::I.J | ~ error[E0423]: expected value, found module `a` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:37:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:42:5 | LL | a.b.f(); - | ^-- - | | - | help: use the path separator to refer to an item: `a::b` + | ^- help: use the path separator to refer to an item: `::` error[E0423]: expected value, found module `a::b` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:40:12 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:46:12 | LL | pub const I: i32 = 1; | --------------------- similarly named constant `I` defined here @@ -60,7 +52,7 @@ LL | v.push(a::b); | help: a constant with a similar name exists: `I` error[E0423]: expected value, found module `a::b` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:45:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:52:5 | LL | pub const I: i32 = 1; | --------------------- similarly named constant `I` defined here @@ -71,14 +63,14 @@ LL | a::b.f() help: use the path separator to refer to an item | LL | a::b::f() - | ~~~~~~~ + | ~~ help: a constant with a similar name exists | LL | a::I.f() | ~ error[E0423]: expected value, found module `a::b` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:50:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:59:5 | LL | pub const I: i32 = 1; | --------------------- similarly named constant `I` defined here @@ -89,7 +81,7 @@ LL | a::b | help: a constant with a similar name exists: `I` error[E0423]: expected function, found module `a::b` - --> $DIR/suggest-path-instead-of-mod-dot-item.rs:55:5 + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:65:5 | LL | pub const I: i32 = 1; | --------------------- similarly named constant `I` defined here @@ -99,6 +91,50 @@ LL | a::b() | | | help: a constant with a similar name exists: `I` -error: aborting due to 9 previous errors +error[E0423]: expected value, found module `a` + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:72:9 + | +LL | a + | ^ not a value +... +LL | module!().g::<()>(); // no `help` here! + | --------- in this macro invocation + | + = note: this error originates in the macro `module` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found module `a` + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:72:9 + | +LL | a + | ^ not a value +... +LL | module!().g; // no `help` here! + | --------- in this macro invocation + | + = note: this error originates in the macro `module` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found module `a` + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:80:9 + | +LL | a.f() + | ^- help: use the path separator to refer to an item: `::` +... +LL | let _ = create!(method); + | --------------- in this macro invocation + | + = note: this error originates in the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0423]: expected value, found module `a` + --> $DIR/suggest-path-instead-of-mod-dot-item.rs:85:9 + | +LL | a.f + | ^- help: use the path separator to refer to an item: `::` +... +LL | let _ = create!(field); + | -------------- in this macro invocation + | + = note: this error originates in the macro `create` (in Nightly builds, run with -Z macro-backtrace for more info) + +error: aborting due to 13 previous errors For more information about this error, try `rustc --explain E0423`. diff --git a/src/test/ui/suggestions/assoc-const-as-field.stderr b/src/test/ui/suggestions/assoc-const-as-field.stderr index 5e746ecb2f2..78e5634b2de 100644 --- a/src/test/ui/suggestions/assoc-const-as-field.stderr +++ b/src/test/ui/suggestions/assoc-const-as-field.stderr @@ -2,9 +2,7 @@ error[E0423]: expected value, found struct `Mod::Foo` --> $DIR/assoc-const-as-field.rs:11:9 | LL | foo(Mod::Foo.Bar); - | ^^^^^^^^---- - | | - | help: use the path separator to refer to an item: `Mod::Foo::Bar` + | ^^^^^^^^- help: use the path separator to refer to an item: `::` error: aborting due to previous error