diff --git a/compiler/rustc_typeck/src/check/demand.rs b/compiler/rustc_typeck/src/check/demand.rs index 2d84e7830c21b..d879b6e97dcfb 100644 --- a/compiler/rustc_typeck/src/check/demand.rs +++ b/compiler/rustc_typeck/src/check/demand.rs @@ -374,6 +374,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } } + /// Returns whether the given expression is an `else if`. + crate fn is_else_if_block(&self, expr: &hir::Expr<'_>) -> bool { + if let hir::ExprKind::If(..) = expr.kind { + let parent_id = self.tcx.hir().get_parent_node(expr.hir_id); + if let Some(Node::Expr(hir::Expr { + kind: hir::ExprKind::If(_, _, Some(else_expr)), + .. + })) = self.tcx.hir().find(parent_id) + { + return else_expr.hir_id == expr.hir_id; + } + } + false + } + /// This function is used to determine potential "simple" improvements or users' errors and /// provide them useful help. For example: /// @@ -660,12 +675,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }; let suggestion = if is_struct_pat_shorthand_field { format!("{}: *{}", code, code) + } else if self.is_else_if_block(expr) { + // Don't suggest nonsense like `else *if` + return None; } else if let Some(expr) = self.maybe_get_block_expr(expr.hir_id) { - if let Ok(inner_code) = sm.span_to_snippet(expr.span) { - format!("*{}", inner_code) - } else { - format!("*{}", code) - } + format!("*{}", sm.span_to_snippet(expr.span).unwrap_or(code)) } else { format!("*{}", code) }; diff --git a/src/test/ui/deref-suggestion.stderr b/src/test/ui/deref-suggestion.stderr index 1720421c7f60e..632a279d79623 100644 --- a/src/test/ui/deref-suggestion.stderr +++ b/src/test/ui/deref-suggestion.stderr @@ -125,16 +125,6 @@ LL | || }; | ||_____| | |______`if` and `else` have incompatible types | expected `i32`, found `&{integer}` - | -help: consider dereferencing the borrow - | -LL | } else *if true { -LL | -LL | b -LL | } else { -LL | &0 -LL | }; - | error: aborting due to 13 previous errors