diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs index 7f78f5fb8a7b..be618eb664c3 100644 --- a/compiler/rustc_hir_typeck/src/demand.rs +++ b/compiler/rustc_hir_typeck/src/demand.rs @@ -43,7 +43,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { || self.suggest_block_to_brackets_peeling_refs(err, expr, expr_ty, expected) || self.suggest_copied_or_cloned(err, expr, expr_ty, expected) || self.suggest_into(err, expr, expr_ty, expected) - || self.suggest_option_to_bool(err, expr, expr_ty, expected); + || self.suggest_option_to_bool(err, expr, expr_ty, expected) + || self.suggest_floating_point_literal(err, expr, expected); self.note_type_is_not_clone(err, expected, expr_ty, expr); self.note_need_for_fn_pointer(err, expected, expr_ty); diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs index a14759e254c4..fb8669e949cd 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs @@ -1204,6 +1204,27 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } + #[instrument(skip(self, err))] + pub(crate) fn suggest_floating_point_literal( + &self, + err: &mut Diagnostic, + expr: &hir::Expr<'_>, + expected_ty: Ty<'tcx>, + ) -> bool { + if let ExprKind::Struct(QPath::LangItem(LangItem::Range, ..), [start, _], _) = expr.kind + && expected_ty.is_floating_point() + { + err.span_suggestion_verbose( + self.tcx.sess.source_map().next_point(start.span), + "remove the unnecessary `.` operator to to use a floating point literal", + "", + Applicability::MachineApplicable, + ); + return true; + } + false + } + fn is_loop(&self, id: hir::HirId) -> bool { let node = self.tcx.hir().get(id); matches!(node, Node::Expr(Expr { kind: ExprKind::Loop(..), .. })) diff --git a/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs new file mode 100644 index 000000000000..b1eda63d56e2 --- /dev/null +++ b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs @@ -0,0 +1,6 @@ +fn main() { + let _: f64 = 0..10; //~ ERROR mismatched types + let _: f64 = 0..; //~ ERROR mismatched types + let _: f64 = ..10; //~ ERROR mismatched types + let _: f64 = std::ops::Range { start: 0, end: 1 }; //~ ERROR mismatched types +} diff --git a/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr new file mode 100644 index 000000000000..2f1d7dc230f4 --- /dev/null +++ b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr @@ -0,0 +1,52 @@ +error[E0308]: mismatched types + --> $DIR/unnecessary_dot_for_floating_point_literal.rs:2:18 + | +LL | let _: f64 = 0..10; + | --- ^^^^^ expected `f64`, found struct `std::ops::Range` + | | + | expected due to this + | + = note: expected type `f64` + found struct `std::ops::Range<{integer}>` +help: remove the unnecessary `.` operator to to use a floating point literal + | +LL - let _: f64 = 0..10; +LL + let _: f64 = 0.10; + | + +error[E0308]: mismatched types + --> $DIR/unnecessary_dot_for_floating_point_literal.rs:3:18 + | +LL | let _: f64 = 0..; + | --- ^^^ expected `f64`, found struct `RangeFrom` + | | + | expected due to this + | + = note: expected type `f64` + found struct `RangeFrom<{integer}>` + +error[E0308]: mismatched types + --> $DIR/unnecessary_dot_for_floating_point_literal.rs:4:18 + | +LL | let _: f64 = ..10; + | --- ^^^^ expected `f64`, found struct `RangeTo` + | | + | expected due to this + | + = note: expected type `f64` + found struct `RangeTo<{integer}>` + +error[E0308]: mismatched types + --> $DIR/unnecessary_dot_for_floating_point_literal.rs:5:18 + | +LL | let _: f64 = std::ops::Range { start: 0, end: 1 }; + | --- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `f64`, found struct `std::ops::Range` + | | + | expected due to this + | + = note: expected type `f64` + found struct `std::ops::Range<{integer}>` + +error: aborting due to 4 previous errors + +For more information about this error, try `rustc --explain E0308`.