diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index 0466e76475da3..e191fadc01beb 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -2220,6 +2220,7 @@ impl<'a> Resolver<'a> { -> PathResolution { let ns = source.namespace(); let is_expected = &|def| source.is_expected(def); + let is_enum_variant = &|def| if let Def::Variant(..) = def { true } else { false }; // Base error is amended with one short label and possibly some longer helps/notes. let report_errors = |this: &mut Self, def: Option<Def>| { @@ -2270,6 +2271,21 @@ impl<'a> Resolver<'a> { if !candidates.is_empty() { // Report import candidates as help and proceed searching for labels. show_candidates(&mut err, &candidates, def.is_some()); + } else if is_expected(Def::Enum(DefId::local(CRATE_DEF_INDEX))) { + let enum_candidates = this.lookup_import_candidates(name, ns, is_enum_variant); + let mut enum_candidates = enum_candidates.iter() + .map(|suggestion| import_candidate_to_paths(&suggestion)).collect::<Vec<_>>(); + enum_candidates.sort(); + for (sp, variant_path, enum_path) in enum_candidates { + let msg = format!("there is an enum variant `{}`, did you mean to use `{}`?", + variant_path, + enum_path); + if sp == DUMMY_SP { + err.help(&msg); + } else { + err.span_help(sp, &msg); + } + } } if path.len() == 1 && this.self_type_is_available() { if let Some(candidate) = this.lookup_assoc_candidate(name, ns, is_expected) { @@ -3422,6 +3438,22 @@ fn path_names_to_string(path: &Path) -> String { names_to_string(&path.segments.iter().map(|seg| seg.identifier).collect::<Vec<_>>()) } +/// Get the path for an enum and the variant from an `ImportSuggestion` for an enum variant. +fn import_candidate_to_paths(suggestion: &ImportSuggestion) -> (Span, String, String) { + let variant_path = &suggestion.path; + let variant_path_string = path_names_to_string(variant_path); + + let path_len = suggestion.path.segments.len(); + let enum_path = ast::Path { + span: suggestion.path.span, + segments: suggestion.path.segments[0..path_len - 1].to_vec(), + }; + let enum_path_string = path_names_to_string(&enum_path); + + (suggestion.path.span, variant_path_string, enum_path_string) +} + + /// When an entity with a given name is not available in scope, we search for /// entities with that name in all crates. This method allows outputting the /// results of this search in a programmer-friendly way diff --git a/src/test/compile-fail/issue-35675.rs b/src/test/compile-fail/issue-35675.rs new file mode 100644 index 0000000000000..f990c2c42fe14 --- /dev/null +++ b/src/test/compile-fail/issue-35675.rs @@ -0,0 +1,67 @@ +// Copyright 2017 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +enum Fruit { + Apple(i64), + //~^ HELP there is an enum variant `Fruit::Apple`, did you mean to use `Fruit`? + //~| HELP there is an enum variant `Fruit::Apple`, did you mean to use `Fruit`? + Orange(i64), +} + +fn should_return_fruit() -> Apple { + //~^ ERROR cannot find type `Apple` in this scope + //~| NOTE not found in this scope + Apple(5) + //~^ ERROR cannot find function `Apple` in this scope + //~| NOTE not found in this scope + //~| HELP possible candidate is found in another module, you can import it into scope +} + +fn should_return_fruit_too() -> Fruit::Apple { + //~^ ERROR expected type, found variant `Fruit::Apple` + //~| NOTE not a type + Apple(5) + //~^ ERROR cannot find function `Apple` in this scope + //~| NOTE not found in this scope + //~| HELP possible candidate is found in another module, you can import it into scope +} + +fn foo() -> Ok { + //~^ ERROR expected type, found variant `Ok` + //~| NOTE not a type + //~| HELP there is an enum variant + //~| HELP there is an enum variant + Ok(()) +} + +fn bar() -> Variant3 { + //~^ ERROR cannot find type `Variant3` in this scope + //~| NOTE not found in this scope +} + +fn qux() -> Some { + //~^ ERROR expected type, found variant `Some` + //~| NOTE not a type + //~| HELP there is an enum variant + //~| HELP there is an enum variant + Some(1) +} + +fn main() {} + +mod x { + enum Enum { + Variant1, + Variant2(), + Variant3(usize), + //~^ HELP there is an enum variant `x::Enum::Variant3`, did you mean to use `x::Enum`? + Variant4 {}, + } +}