bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Rollup merge of #98119 - EdwinRy:path-parenthesized-type-error, r=estebank

Browse source 
Refactor path segment parameter error

This PR attempts to rewrite the error handling for an unexpected parenthesised type parameters to:
- Use provided data instead of re-parsing the whole span
- Add a multipart suggestion to reflect on the changes with an underline
- Remove the unnecessary "if" nesting
This commit is contained in:
Yuki Okushi 2022-06-16 07:24:43 +09:00 • committed by GitHub
commit bfc6c90115
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
7 changed files with 61 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files

45
compiler/rustc_ast_lowering/src/path.rs
View file

@ -196,25 +196,32 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
ParenthesizedGenericArgs::Err => {
let mut err = struct_span_err!(self.sess, data.span, E0214, "{}", msg);
err.span_label(data.span, "only `Fn` traits may use parentheses");
if let Ok(snippet) = self.sess.source_map().span_to_snippet(data.span) {
// Do not suggest going from `Trait()` to `Trait<>`
if !data.inputs.is_empty() {
// Suggest replacing `(` and `)` with `<` and `>`
// The snippet may be missing the closing `)`, skip that case
if snippet.ends_with(')') {
if let Some(split) = snippet.find('(') {
let trait_name = &snippet[0..split];
let args = &snippet[split + 1..snippet.len() - 1];
err.span_suggestion(
data.span,
"use angle brackets instead",
format!("{}<{}>", trait_name, args),
Applicability::MaybeIncorrect,
);
}
}
}
};
// Suggest replacing parentheses with angle brackets `Trait(params...)` to `Trait<params...>`
if !data.inputs.is_empty() {
// Start of the span to the 1st character of 1st argument
let open_param = data.inputs_span.shrink_to_lo().to(data
.inputs
.first()
.unwrap()
.span
.shrink_to_lo());
// Last character position of last argument to the end of the span
let close_param = data
.inputs
.last()
.unwrap()
.span
.shrink_to_hi()
.to(data.inputs_span.shrink_to_hi());
err.multipart_suggestion(
&format!("use angle brackets instead",),
vec![
(open_param, String::from("<")),
(close_param, String::from(">")),
],
Applicability::MaybeIncorrect,
);
}
err.emit();
(
self.lower_angle_bracketed_parameter_data(