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

Fix #104086, Tighten the 'introduce new binding' suggestion

Browse source
This commit is contained in:
yukang 2022-11-09 16:43:37 +08:00
parent bc2504a83c
commit 952df48948
3 changed files with 109 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

25
compiler/rustc_resolve/src/late/diagnostics.rs
View file

@ -1810,18 +1810,27 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
false
}
fn let_binding_suggestion(&self, err: &mut Diagnostic, ident_span: Span) -> bool {
fn let_binding_suggestion(&mut self, err: &mut Diagnostic, ident_span: Span) -> bool {
// try to give a suggestion for this pattern: `name = 1`, which is common in other languages
let mut added_suggestion = false;
if let Some(Expr { kind: ExprKind::Assign(lhs, _rhs, _), .. }) = self.diagnostic_metadata.in_assignment &&
let ast::ExprKind::Path(None, _) = lhs.kind {
if let Some(Expr { kind: ExprKind::Assign(lhs, rhs, _), .. }) =
self.diagnostic_metadata.in_assignment
{
let is_rhs_assign = match rhs.kind {
ExprKind::Assign(..) => true,
_ => false,
};
if let ast::ExprKind::Path(None, _) = lhs.kind && !is_rhs_assign {
let sm = self.r.session.source_map();
let line_span = sm.span_extend_to_line(ident_span);
let ident_name = sm.span_to_snippet(ident_span).unwrap();
// HACK(chenyukang): make sure ident_name is at the starting of the line to protect against macros
if sm
.span_to_snippet(line_span)
.map_or(false, |s| s.trim().starts_with(&ident_name))
// HACK(chenyukang): make sure ident_name is at the starting of the line to protect against macros,
// and avoid some special cases like `x = x = x`
if let Ok(line) = sm.span_to_snippet(line_span) &&
let stripped = line.split_whitespace().collect::<String>() &&
stripped.trim().starts_with(&ident_name) &&
stripped.matches(&format!("{}=", &ident_name)).count() == 1
{
err.span_suggestion_verbose(
ident_span.shrink_to_lo(),
@ -1832,6 +1841,8 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
added_suggestion = true;
}
}
self.diagnostic_metadata.in_assignment = None;
}
added_suggestion
}