pub(super) fn recover_parens_around_for_head(
&mut self,
pat: P<Pat>,
- expr: &Expr,
begin_paren: Option<Span>,
) -> P<Pat> {
match (&self.token.kind, begin_paren) {
(token::CloseDelim(token::Paren), Some(begin_par_sp)) => {
self.bump();
- let pat_str = self
- // Remove the `(` from the span of the pattern:
- .span_to_snippet(pat.span.trim_start(begin_par_sp).unwrap())
- .unwrap_or_else(|_| pprust::pat_to_string(&pat));
-
- self.struct_span_err(self.prev_token.span, "unexpected closing `)`")
- .span_label(begin_par_sp, "opening `(`")
- .span_suggestion(
- begin_par_sp.to(self.prev_token.span),
- "remove parenthesis in `for` loop",
- format!("{} in {}", pat_str, pprust::expr_to_string(&expr)),
- // With e.g. `for (x) in y)` this would replace `(x) in y)`
- // with `x) in y)` which is syntactically invalid.
- // However, this is prevented before we get here.
- Applicability::MachineApplicable,
- )
- .emit();
+ self.struct_span_err(
+ MultiSpan::from_spans(vec![begin_par_sp, self.prev_token.span]),
+ "unexpected parenthesis surrounding `for` loop head",
+ )
+ .multipart_suggestion(
+ "remove parenthesis in `for` loop",
+ vec![(begin_par_sp, String::new()), (self.prev_token.span, String::new())],
+ // With e.g. `for (x) in y)` this would replace `(x) in y)`
+ // with `x) in y)` which is syntactically invalid.
+ // However, this is prevented before we get here.
+ Applicability::MachineApplicable,
+ )
+ .emit();
// Unwrap `(pat)` into `pat` to avoid the `unused_parens` lint.
pat.and_then(|pat| match pat.kind {
{
let rfc_note = "anonymous parameters are removed in the 2018 edition (see RFC 1685)";
- let (ident, self_sugg, param_sugg, type_sugg) = match pat.kind {
- PatKind::Ident(_, ident, _) => (
- ident,
- format!("self: {}", ident),
- format!("{}: TypeName", ident),
- format!("_: {}", ident),
- ),
- // Also catches `fn foo(&a)`.
- PatKind::Ref(ref pat, mutab)
- if matches!(pat.clone().into_inner().kind, PatKind::Ident(..)) =>
- {
- match pat.clone().into_inner().kind {
- PatKind::Ident(_, ident, _) => {
- let mutab = mutab.prefix_str();
- (
- ident,
- format!("self: &{}{}", mutab, ident),
- format!("{}: &{}TypeName", ident, mutab),
- format!("_: &{}{}", mutab, ident),
- )
+ let (ident, self_sugg, param_sugg, type_sugg, self_span, param_span, type_span) =
+ match pat.kind {
+ PatKind::Ident(_, ident, _) => (
+ ident,
+ "self: ".to_string(),
+ ": TypeName".to_string(),
+ "_: ".to_string(),
+ pat.span.shrink_to_lo(),
+ pat.span.shrink_to_hi(),
+ pat.span.shrink_to_lo(),
+ ),
+ // Also catches `fn foo(&a)`.
+ PatKind::Ref(ref inner_pat, mutab)
+ if matches!(inner_pat.clone().into_inner().kind, PatKind::Ident(..)) =>
+ {
+ match inner_pat.clone().into_inner().kind {
+ PatKind::Ident(_, ident, _) => {
+ let mutab = mutab.prefix_str();
+ (
+ ident,
+ "self: ".to_string(),
+ format!("{}: &{}TypeName", ident, mutab),
+ "_: ".to_string(),
+ pat.span.shrink_to_lo(),
+ pat.span,
+ pat.span.shrink_to_lo(),
+ )
+ }
+ _ => unreachable!(),
}
- _ => unreachable!(),
- }
- }
- _ => {
- // Otherwise, try to get a type and emit a suggestion.
- if let Some(ty) = pat.to_ty() {
- err.span_suggestion_verbose(
- pat.span,
- "explicitly ignore the parameter name",
- format!("_: {}", pprust::ty_to_string(&ty)),
- Applicability::MachineApplicable,
- );
- err.note(rfc_note);
}
+ _ => {
+ // Otherwise, try to get a type and emit a suggestion.
+ if let Some(ty) = pat.to_ty() {
+ err.span_suggestion_verbose(
+ pat.span,
+ "explicitly ignore the parameter name",
+ format!("_: {}", pprust::ty_to_string(&ty)),
+ Applicability::MachineApplicable,
+ );
+ err.note(rfc_note);
+ }
- return None;
- }
- };
+ return None;
+ }
+ };
// `fn foo(a, b) {}`, `fn foo(a<x>, b<y>) {}` or `fn foo(usize, usize) {}`
if first_param {
err.span_suggestion(
- pat.span,
+ self_span,
"if this is a `self` type, give it a parameter name",
self_sugg,
Applicability::MaybeIncorrect,
// `fn foo(HashMap: TypeName<u32>)`.
if self.token != token::Lt {
err.span_suggestion(
- pat.span,
+ param_span,
"if this is a parameter name, give it a type",
param_sugg,
Applicability::HasPlaceholders,
);
}
err.span_suggestion(
- pat.span,
+ type_span,
"if this is a type, explicitly ignore the parameter name",
type_sugg,
Applicability::MachineApplicable,
}
match self.parse_expr_res(Restrictions::CONST_EXPR, None) {
Ok(expr) => {
- if token::Comma == self.token.kind || self.token.kind.should_end_const_arg() {
+ // Find a mistake like `MyTrait<Assoc == S::Assoc>`.
+ if token::EqEq == snapshot.token.kind {
+ err.span_suggestion(
+ snapshot.token.span,
+ "if you meant to use an associated type binding, replace `==` with `=`",
+ "=".to_string(),
+ Applicability::MaybeIncorrect,
+ );
+ let value = self.mk_expr_err(start.to(expr.span));
+ err.emit();
+ return Ok(GenericArg::Const(AnonConst { id: ast::DUMMY_NODE_ID, value }));
+ } else if token::Comma == self.token.kind || self.token.kind.should_end_const_arg()
+ {
// Avoid the following output by checking that we consumed a full const arg:
// help: expressions must be enclosed in braces to be used as const generic
// arguments
projects / rust.git / blobdiff