bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Handle empty where-clause better

Browse source
This commit is contained in:
Michael Goulet 2022-06-05 17:37:45 -07:00
parent 8506b7d4e0
commit 9c47afe9fa
23 changed files with 78 additions and 59 deletions
Download patch file Download diff file Expand all files Collapse all files

26
compiler/rustc_hir/src/hir.rs
View file

@ -535,7 +535,8 @@ pub struct GenericParamCount {
pub struct Generics<'hir> {
pub params: &'hir [GenericParam<'hir>],
pub predicates: &'hir [WherePredicate<'hir>],
pub has_where_clause: bool,
pub has_where_clause_predicates: bool,
pub has_where_clause_token: bool,
pub where_clause_span: Span,
pub span: Span,
}
@ -545,7 +546,8 @@ impl<'hir> Generics<'hir> {
const NOPE: Generics<'_> = Generics {
params: &[],
predicates: &[],
has_where_clause: false,
has_where_clause_predicates: false,
has_where_clause_token: false,
where_clause_span: DUMMY_SP,
span: DUMMY_SP,
};
@ -585,17 +587,11 @@ impl<'hir> Generics<'hir> {
if self.predicates.is_empty() { None } else { Some(self.where_clause_span) }
}
/// The `where_span` under normal circumstances points at either the predicates or the empty
/// space where the `where` clause should be. Only of use for diagnostic suggestions.
pub fn span_for_predicates_or_empty_place(&self) -> Span {
self.where_clause_span
}
/// `Span` where further predicates would be suggested, accounting for trailing commas, like
/// in `fn foo<T>(t: T) where T: Foo,` so we don't suggest two trailing commas.
pub fn tail_span_for_predicate_suggestion(&self) -> Span {
let end = self.span_for_predicates_or_empty_place().shrink_to_hi();
if self.has_where_clause {
let end = self.where_clause_span.shrink_to_hi();
if self.has_where_clause_predicates {
self.predicates
.iter()
.filter(|p| p.in_where_clause())
@ -608,6 +604,16 @@ impl<'hir> Generics<'hir> {
}
}
pub fn add_where_or_trailing_comma(&self) -> &'static str {
if self.has_where_clause_predicates {
","
} else if self.has_where_clause_token {
""
} else {
" where"
}
}
pub fn bounds_for_param(
&self,
param_def_id: LocalDefId,