mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rollup merge of #54308 - dsciarra:issue-22692, r=estebank

Browse Source 
Better user experience when attempting to call associated functions with dot notation

Closes #22692
This commit is contained in:
kennytm 2018-10-01 16:12:55 +08:00 committed by GitHub
commit a1f3b0fe74
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 69 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
src/librustc_resolve/lib.rs
View File

@ -3147,11 +3147,11 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
// parser issue where a struct literal is being used on an expression
// where a brace being opened means a block is being started. Look
// ahead for the next text to see if `span` is followed by a `{`.
let cm = this.session.source_map();
let sm = this.session.source_map();
let mut sp = span;
loop {
sp = cm.next_point(sp);
match cm.span_to_snippet(sp) {
sp = sm.next_point(sp);
match sm.span_to_snippet(sp) {
Ok(ref snippet) => {
if snippet.chars().any(|c| { !c.is_whitespace() }) {
break;
@ -3160,20 +3160,51 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
_ => break,
}
}
let followed_by_brace = match cm.span_to_snippet(sp) {
let followed_by_brace = match sm.span_to_snippet(sp) {
Ok(ref snippet) if snippet == "{" => true,
_ => false,
};
if let (PathSource::Expr(None), true) = (source, followed_by_brace) {
err.span_label(
span,
format!("did you mean `({} {{ /* fields */ }})`?", path_str),
);
} else {
err.span_label(
span,
format!("did you mean `{} {{ /* fields */ }}`?", path_str),
);
match source {
PathSource::Expr(Some(parent)) => {
match parent.node {
ExprKind::MethodCall(ref path_assignment, _) => {
err.span_suggestion_with_applicability(
sm.start_point(parent.span)
.to(path_assignment.ident.span),
"use `::` to access an associated function",
format!("{}::{}",
path_str,
path_assignment.ident),
Applicability::MaybeIncorrect
);
return (err, candidates);
},
_ => {
err.span_label(
span,
format!("did you mean `{} {{ /* fields */ }}`?",
path_str),
);
return (err, candidates);
},
}
},
PathSource::Expr(None) if followed_by_brace == true => {
err.span_label(
span,
format!("did you mean `({} {{ /* fields */ }})`?",
path_str),
);
return (err, candidates);
},
_ => {
err.span_label(
span,
format!("did you mean `{} {{ /* fields */ }}`?",
path_str),
);
return (err, candidates);
},
}
}
return (err, candidates);

13
src/test/ui/resolve/issue-22692.rs Normal file
View File

@ -0,0 +1,13 @@
// 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 <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.
fn main() {
let _ = String.new();
}

11
src/test/ui/resolve/issue-22692.stderr Normal file
View File

@ -0,0 +1,11 @@
error[E0423]: expected value, found struct `String`
--> $DIR/issue-22692.rs:12:13
|
LL | let _ = String.new();
| ^^^^^^----
| |
| help: use `::` to access an associated function: `String::new`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0423`.