From aa3fbf87950ed764f91222be2f7ec0fc1e9b1c91 Mon Sep 17 00:00:00 2001 From: Oli Scherer Date: Thu, 29 Sep 2022 14:29:36 +0000 Subject: [PATCH] Split out the error reporting logic into a separate function --- .../rustc_hir_analysis/src/check/callee.rs | 274 +++++++++--------- 1 file changed, 140 insertions(+), 134 deletions(-) diff --git a/compiler/rustc_hir_analysis/src/check/callee.rs b/compiler/rustc_hir_analysis/src/check/callee.rs index c82a31e65cf15..080771844a44c 100644 --- a/compiler/rustc_hir_analysis/src/check/callee.rs +++ b/compiler/rustc_hir_analysis/src/check/callee.rs @@ -394,140 +394,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } ty::FnPtr(sig) => (sig, None), _ => { - let mut unit_variant = None; - if let hir::ExprKind::Path(qpath) = &callee_expr.kind - && let Res::Def(def::DefKind::Ctor(kind, def::CtorKind::Const), _) - = self.typeck_results.borrow().qpath_res(qpath, callee_expr.hir_id) - // Only suggest removing parens if there are no arguments - && arg_exprs.is_empty() - { - let descr = match kind { - def::CtorOf::Struct => "struct", - def::CtorOf::Variant => "enum variant", - }; - let removal_span = - callee_expr.span.shrink_to_hi().to(call_expr.span.shrink_to_hi()); - unit_variant = - Some((removal_span, descr, rustc_hir_pretty::qpath_to_string(qpath))); - } - - let callee_ty = self.resolve_vars_if_possible(callee_ty); - let mut err = type_error_struct!( - self.tcx.sess, - callee_expr.span, - callee_ty, - E0618, - "expected function, found {}", - match &unit_variant { - Some((_, kind, path)) => format!("{kind} `{path}`"), - None => format!("`{callee_ty}`"), - } - ); - - self.identify_bad_closure_def_and_call( - &mut err, - call_expr.hir_id, - &callee_expr.kind, - callee_expr.span, - ); - - if let Some((removal_span, kind, path)) = &unit_variant { - err.span_suggestion_verbose( - *removal_span, - &format!( - "`{path}` is a unit {kind}, and does not take parentheses to be constructed", - ), - "", - Applicability::MachineApplicable, - ); - } - - let mut inner_callee_path = None; - let def = match callee_expr.kind { - hir::ExprKind::Path(ref qpath) => { - self.typeck_results.borrow().qpath_res(qpath, callee_expr.hir_id) - } - hir::ExprKind::Call(ref inner_callee, _) => { - // If the call spans more than one line and the callee kind is - // itself another `ExprCall`, that's a clue that we might just be - // missing a semicolon (Issue #51055) - let call_is_multiline = - self.tcx.sess.source_map().is_multiline(call_expr.span); - if call_is_multiline { - err.span_suggestion( - callee_expr.span.shrink_to_hi(), - "consider using a semicolon here", - ";", - Applicability::MaybeIncorrect, - ); - } - if let hir::ExprKind::Path(ref inner_qpath) = inner_callee.kind { - inner_callee_path = Some(inner_qpath); - self.typeck_results.borrow().qpath_res(inner_qpath, inner_callee.hir_id) - } else { - Res::Err - } - } - _ => Res::Err, - }; - - if !self.maybe_suggest_bad_array_definition(&mut err, call_expr, callee_expr) { - if let Some((maybe_def, output_ty, _)) = self.extract_callable_info(callee_expr, callee_ty) - && !self.type_is_sized_modulo_regions(self.param_env, output_ty, callee_expr.span) - { - let descr = match maybe_def { - DefIdOrName::DefId(def_id) => self.tcx.def_kind(def_id).descr(def_id), - DefIdOrName::Name(name) => name, - }; - err.span_label( - callee_expr.span, - format!("this {descr} returns an unsized value `{output_ty}`, so it cannot be called") - ); - if let DefIdOrName::DefId(def_id) = maybe_def - && let Some(def_span) = self.tcx.hir().span_if_local(def_id) - { - err.span_label(def_span, "the callable type is defined here"); - } - } else { - err.span_label(call_expr.span, "call expression requires function"); - } - } - - if let Some(span) = self.tcx.hir().res_span(def) { - let callee_ty = callee_ty.to_string(); - let label = match (unit_variant, inner_callee_path) { - (Some((_, kind, path)), _) => Some(format!("{kind} `{path}` defined here")), - (_, Some(hir::QPath::Resolved(_, path))) => self - .tcx - .sess - .source_map() - .span_to_snippet(path.span) - .ok() - .map(|p| format!("`{p}` defined here returns `{callee_ty}`")), - _ => { - match def { - // Emit a different diagnostic for local variables, as they are not - // type definitions themselves, but rather variables *of* that type. - Res::Local(hir_id) => Some(format!( - "`{}` has type `{}`", - self.tcx.hir().name(hir_id), - callee_ty - )), - Res::Def(kind, def_id) if kind.ns() == Some(Namespace::ValueNS) => { - Some(format!( - "`{}` defined here", - self.tcx.def_path_str(def_id), - )) - } - _ => Some(format!("`{callee_ty}` defined here")), - } - } - }; - if let Some(label) = label { - err.span_label(span, label); - } - } - err.emit(); + self.report_invalid_callee(call_expr, callee_expr, callee_ty, arg_exprs); // This is the "default" function signature, used in case of error. // In that case, we check each argument against "error" in order to @@ -574,6 +441,145 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { fn_sig.output() } + fn report_invalid_callee( + &self, + call_expr: &'tcx hir::Expr<'tcx>, + callee_expr: &'tcx hir::Expr<'tcx>, + callee_ty: Ty<'tcx>, + arg_exprs: &'tcx [hir::Expr<'tcx>], + ) { + let mut unit_variant = None; + if let hir::ExprKind::Path(qpath) = &callee_expr.kind + && let Res::Def(def::DefKind::Ctor(kind, def::CtorKind::Const), _) + = self.typeck_results.borrow().qpath_res(qpath, callee_expr.hir_id) + // Only suggest removing parens if there are no arguments + && arg_exprs.is_empty() + { + let descr = match kind { + def::CtorOf::Struct => "struct", + def::CtorOf::Variant => "enum variant", + }; + let removal_span = + callee_expr.span.shrink_to_hi().to(call_expr.span.shrink_to_hi()); + unit_variant = + Some((removal_span, descr, rustc_hir_pretty::qpath_to_string(qpath))); + } + + let callee_ty = self.resolve_vars_if_possible(callee_ty); + let mut err = type_error_struct!( + self.tcx.sess, + callee_expr.span, + callee_ty, + E0618, + "expected function, found {}", + match &unit_variant { + Some((_, kind, path)) => format!("{kind} `{path}`"), + None => format!("`{callee_ty}`"), + } + ); + + self.identify_bad_closure_def_and_call( + &mut err, + call_expr.hir_id, + &callee_expr.kind, + callee_expr.span, + ); + + if let Some((removal_span, kind, path)) = &unit_variant { + err.span_suggestion_verbose( + *removal_span, + &format!( + "`{path}` is a unit {kind}, and does not take parentheses to be constructed", + ), + "", + Applicability::MachineApplicable, + ); + } + + let mut inner_callee_path = None; + let def = match callee_expr.kind { + hir::ExprKind::Path(ref qpath) => { + self.typeck_results.borrow().qpath_res(qpath, callee_expr.hir_id) + } + hir::ExprKind::Call(ref inner_callee, _) => { + // If the call spans more than one line and the callee kind is + // itself another `ExprCall`, that's a clue that we might just be + // missing a semicolon (Issue #51055) + let call_is_multiline = self.tcx.sess.source_map().is_multiline(call_expr.span); + if call_is_multiline { + err.span_suggestion( + callee_expr.span.shrink_to_hi(), + "consider using a semicolon here", + ";", + Applicability::MaybeIncorrect, + ); + } + if let hir::ExprKind::Path(ref inner_qpath) = inner_callee.kind { + inner_callee_path = Some(inner_qpath); + self.typeck_results.borrow().qpath_res(inner_qpath, inner_callee.hir_id) + } else { + Res::Err + } + } + _ => Res::Err, + }; + + if !self.maybe_suggest_bad_array_definition(&mut err, call_expr, callee_expr) { + if let Some((maybe_def, output_ty, _)) = self.extract_callable_info(callee_expr, callee_ty) + && !self.type_is_sized_modulo_regions(self.param_env, output_ty, callee_expr.span) + { + let descr = match maybe_def { + DefIdOrName::DefId(def_id) => self.tcx.def_kind(def_id).descr(def_id), + DefIdOrName::Name(name) => name, + }; + err.span_label( + callee_expr.span, + format!("this {descr} returns an unsized value `{output_ty}`, so it cannot be called") + ); + if let DefIdOrName::DefId(def_id) = maybe_def + && let Some(def_span) = self.tcx.hir().span_if_local(def_id) + { + err.span_label(def_span, "the callable type is defined here"); + } + } else { + err.span_label(call_expr.span, "call expression requires function"); + } + } + + if let Some(span) = self.tcx.hir().res_span(def) { + let callee_ty = callee_ty.to_string(); + let label = match (unit_variant, inner_callee_path) { + (Some((_, kind, path)), _) => Some(format!("{kind} `{path}` defined here")), + (_, Some(hir::QPath::Resolved(_, path))) => self + .tcx + .sess + .source_map() + .span_to_snippet(path.span) + .ok() + .map(|p| format!("`{p}` defined here returns `{callee_ty}`")), + _ => { + match def { + // Emit a different diagnostic for local variables, as they are not + // type definitions themselves, but rather variables *of* that type. + Res::Local(hir_id) => Some(format!( + "`{}` has type `{}`", + self.tcx.hir().name(hir_id), + callee_ty + )), + Res::Def(kind, def_id) if kind.ns() == Some(Namespace::ValueNS) => { + Some(format!("`{}` defined here", self.tcx.def_path_str(def_id),)) + } + _ => Some(format!("`{callee_ty}` defined here")), + } + } + }; + if let Some(label) = label { + err.span_label(span, label); + } + } + err.emit(); + } + fn confirm_deferred_closure_call( &self, call_expr: &'tcx hir::Expr<'tcx>,