diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index a68c89deea5b6..09ac24a33faff 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -2981,13 +2981,13 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> { // Make the base error. let expected = source.descr_expected(); let path_str = names_to_string(path); + let item_str = path[path.len() - 1]; let code = source.error_code(def.is_some()); let (base_msg, fallback_label, base_span) = if let Some(def) = def { (format!("expected {}, found {} `{}`", expected, def.kind_name(), path_str), format!("not a {}", expected), span) } else { - let item_str = path[path.len() - 1]; let item_span = path[path.len() - 1].span; let (mod_prefix, mod_str) = if path.len() == 1 { (String::new(), "this scope".to_string()) @@ -3010,6 +3010,20 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> { let code = DiagnosticId::Error(code.into()); let mut err = this.session.struct_span_err_with_code(base_span, &base_msg, code); + // Emit help message for fake-self from other languages like `this`(javascript) + let fake_self: Vec = ["this", "my"].iter().map( + |s| Ident::from_str(*s) + ).collect(); + if fake_self.contains(&item_str) + && this.self_value_is_available(path[0].span, span) { + err.span_suggestion_with_applicability( + span, + "did you mean", + "self".to_string(), + Applicability::MaybeIncorrect, + ); + } + // Emit special messages for unresolved `Self` and `self`. if is_self_type(path, ns) { __diagnostic_used!(E0411); diff --git a/src/test/ui/self/suggest-self.rs b/src/test/ui/self/suggest-self.rs new file mode 100644 index 0000000000000..f648d781cafea --- /dev/null +++ b/src/test/ui/self/suggest-self.rs @@ -0,0 +1,52 @@ +// Copyright 2018 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +struct Foo { + x: i32, +} + +impl Foo { + fn this1(&self) -> i32 { + let this = self; + let a = 1; + this.x + } + + fn this2(&self) -> i32 { + let a = Foo { + x: 2 + }; + let this = a; + this.x + } + + fn foo(&self) -> i32 { + this.x + //~^ ERROR cannot find value `this` in this scope + } + + fn bar(&self) -> i32 { + this.foo() + //~^ ERROR cannot find value `this` in this scope + } + + fn baz(&self) -> i32 { + my.bar() + //~^ ERROR cannot find value `my` in this scope + } +} + +fn main() { + let this = vec![1, 2, 3]; + let my = vec![1, 2, 3]; + let len = this.len(); + let len = my.len(); +} + diff --git a/src/test/ui/self/suggest-self.stderr b/src/test/ui/self/suggest-self.stderr new file mode 100644 index 0000000000000..9035dc0fe7d29 --- /dev/null +++ b/src/test/ui/self/suggest-self.stderr @@ -0,0 +1,30 @@ +error[E0425]: cannot find value `this` in this scope + --> $DIR/suggest-self.rs:31:9 + | +LL | this.x + | ^^^^ + | | + | not found in this scope + | help: did you mean: `self` + +error[E0425]: cannot find value `this` in this scope + --> $DIR/suggest-self.rs:36:9 + | +LL | this.foo() + | ^^^^ + | | + | not found in this scope + | help: did you mean: `self` + +error[E0425]: cannot find value `my` in this scope + --> $DIR/suggest-self.rs:41:9 + | +LL | my.bar() + | ^^ + | | + | not found in this scope + | help: did you mean: `self` + +error: aborting due to 3 previous errors + +For more information about this error, try `rustc --explain E0425`.