From 762bdbfce72e2c3b3f81f457f77cd12736ba8a7f Mon Sep 17 00:00:00 2001 From: Jack Huey <31162821+jackh726@users.noreply.github.com> Date: Fri, 24 Dec 2021 22:57:31 -0500 Subject: [PATCH 1/2] Change signature of point_at_arg_instead_of_call_if_possible --- .../rustc_typeck/src/check/fn_ctxt/checks.rs | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs index e42d94a6f40..820a4054cb4 100644 --- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs +++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs @@ -315,13 +315,15 @@ pub(in super::super) fn check_argument_types( assert_eq!(expected_input_tys.len(), formal_input_tys.len()); + let provided_arg_count: usize = provided_args.len(); + // Keep track of the fully coerced argument types - let mut final_arg_types: Vec<(usize, Ty<'_>, Ty<'_>)> = vec![]; + let mut final_arg_types: Vec, Ty<'_>)>> = vec![None; provided_arg_count]; // We introduce a helper function to demand that a given argument satisfy a given input // This is more complicated than just checking type equality, as arguments could be coerced // This version writes those types back so further type checking uses the narrowed types - let demand_compatible = |idx, final_arg_types: &mut Vec<(usize, Ty<'tcx>, Ty<'tcx>)>| { + let demand_compatible = |idx, final_arg_types: &mut Vec, Ty<'tcx>)>>| { let formal_input_ty: Ty<'tcx> = formal_input_tys[idx]; let expected_input_ty: Ty<'tcx> = expected_input_tys[idx]; let provided_arg = &provided_args[idx]; @@ -340,7 +342,7 @@ pub(in super::super) fn check_argument_types( let coerced_ty = expectation.only_has_type(self).unwrap_or(formal_input_ty); // Keep track of these for below - final_arg_types.push((idx, checked_ty, coerced_ty)); + final_arg_types[idx] = Some((checked_ty, coerced_ty)); // Cause selection errors caused by resolving a single argument to point at the // argument and not the call. This is otherwise redundant with the `demand_coerce` @@ -975,7 +977,7 @@ fn finish_resolving_struct_path( fn point_at_arg_instead_of_call_if_possible( &self, errors: &mut Vec>, - final_arg_types: &[(usize, Ty<'tcx>, Ty<'tcx>)], + final_arg_types: &[Option<(Ty<'tcx>, Ty<'tcx>)>], expr: &'tcx hir::Expr<'tcx>, call_sp: Span, args: &'tcx [hir::Expr<'tcx>], @@ -1030,8 +1032,12 @@ fn unpeel_to_top( // `FulfillmentError`. let mut referenced_in = final_arg_types .iter() - .map(|&(i, checked_ty, _)| (i, checked_ty)) - .chain(final_arg_types.iter().map(|&(i, _, coerced_ty)| (i, coerced_ty))) + .enumerate() + .filter_map(|(i, arg)| match arg { + Some((checked_ty, coerce_ty)) => Some([(i, *checked_ty), (i, *coerce_ty)]), + _ => None, + }) + .flatten() .flat_map(|(i, ty)| { let ty = self.resolve_vars_if_possible(ty); // We walk the argument type because the argument's type could have From ce31f68f9e5886959350a85aaad92bc4374c81ab Mon Sep 17 00:00:00 2001 From: Jack Huey <31162821+jackh726@users.noreply.github.com> Date: Thu, 20 Jan 2022 10:18:23 -0500 Subject: [PATCH 2/2] Move param count error emission to near end of check_argument_types --- .../rustc_typeck/src/check/fn_ctxt/checks.rs | 261 +++++++++--------- .../mismatched_types/overloaded-calls-bad.rs | 1 + .../overloaded-calls-bad.stderr | 8 +- 3 files changed, 140 insertions(+), 130 deletions(-) diff --git a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs index 820a4054cb4..c39199f84b5 100644 --- a/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs +++ b/compiler/rustc_typeck/src/check/fn_ctxt/checks.rs @@ -127,136 +127,19 @@ pub(in super::super) fn check_argument_types( let expected_arg_count = formal_input_tys.len(); - let param_count_error = |expected_count: usize, - arg_count: usize, - error_code: &str, - c_variadic: bool, - sugg_unit: bool| { - let (span, start_span, args, ctor_of) = match &call_expr.kind { - hir::ExprKind::Call( - hir::Expr { - span, - kind: - hir::ExprKind::Path(hir::QPath::Resolved( - _, - hir::Path { res: Res::Def(DefKind::Ctor(of, _), _), .. }, - )), - .. - }, - args, - ) => (*span, *span, &args[..], Some(of)), - hir::ExprKind::Call(hir::Expr { span, .. }, args) => { - (*span, *span, &args[..], None) - } - hir::ExprKind::MethodCall(path_segment, args, _) => ( - path_segment.ident.span, - // `sp` doesn't point at the whole `foo.bar()`, only at `bar`. - path_segment - .args - .and_then(|args| args.args.iter().last()) - // Account for `foo.bar::()`. - .map(|arg| { - // Skip the closing `>`. - tcx.sess - .source_map() - .next_point(tcx.sess.source_map().next_point(arg.span())) - }) - .unwrap_or(path_segment.ident.span), - &args[1..], // Skip the receiver. - None, // methods are never ctors - ), - k => span_bug!(call_span, "checking argument types on a non-call: `{:?}`", k), - }; - let arg_spans = if provided_args.is_empty() { - // foo() - // ^^^-- supplied 0 arguments - // | - // expected 2 arguments - vec![tcx.sess.source_map().next_point(start_span).with_hi(call_span.hi())] - } else { - // foo(1, 2, 3) - // ^^^ - - - supplied 3 arguments - // | - // expected 2 arguments - args.iter().map(|arg| arg.span).collect::>() - }; - - let mut err = tcx.sess.struct_span_err_with_code( - span, - &format!( - "this {} takes {}{} but {} {} supplied", - match ctor_of { - Some(CtorOf::Struct) => "struct", - Some(CtorOf::Variant) => "enum variant", - None => "function", - }, - if c_variadic { "at least " } else { "" }, - potentially_plural_count(expected_count, "argument"), - potentially_plural_count(arg_count, "argument"), - if arg_count == 1 { "was" } else { "were" } - ), - DiagnosticId::Error(error_code.to_owned()), - ); - let label = format!("supplied {}", potentially_plural_count(arg_count, "argument")); - for (i, span) in arg_spans.into_iter().enumerate() { - err.span_label( - span, - if arg_count == 0 || i + 1 == arg_count { &label } else { "" }, - ); - } - - if let Some(def_id) = fn_def_id { - if let Some(def_span) = tcx.def_ident_span(def_id) { - let mut spans: MultiSpan = def_span.into(); - - let params = tcx - .hir() - .get_if_local(def_id) - .and_then(|node| node.body_id()) - .into_iter() - .map(|id| tcx.hir().body(id).params) - .flatten(); - - for param in params { - spans.push_span_label(param.span, String::new()); - } - - let def_kind = tcx.def_kind(def_id); - err.span_note(spans, &format!("{} defined here", def_kind.descr(def_id))); - } - } - - if sugg_unit { - let sugg_span = tcx.sess.source_map().end_point(call_expr.span); - // remove closing `)` from the span - let sugg_span = sugg_span.shrink_to_lo(); - err.span_suggestion( - sugg_span, - "expected the unit value `()`; create it with empty parentheses", - String::from("()"), - Applicability::MachineApplicable, - ); - } else { - err.span_label( - span, - format!( - "expected {}{}", - if c_variadic { "at least " } else { "" }, - potentially_plural_count(expected_count, "argument") - ), - ); - } - err.emit(); - }; + // expected_count, arg_count, error_code, sugg_unit + let mut error: Option<(usize, usize, &str, bool)> = None; + // If the arguments should be wrapped in a tuple (ex: closures), unwrap them here let (formal_input_tys, expected_input_tys) = if tuple_arguments == TupleArguments { let tuple_type = self.structurally_resolved_type(call_span, formal_input_tys[0]); match tuple_type.kind() { - ty::Tuple(arg_types) if arg_types.len() != provided_args.len() => { - param_count_error(arg_types.len(), provided_args.len(), "E0057", false, false); - (self.err_args(provided_args.len()), vec![]) - } + // We expected a tuple and got a tuple ty::Tuple(arg_types) => { + // Argument length differs + if arg_types.len() != provided_args.len() { + error = Some((arg_types.len(), provided_args.len(), "E0057", false)); + } let expected_input_tys = match expected_input_tys.get(0) { Some(&ty) => match ty.kind() { ty::Tuple(ref tys) => tys.iter().map(|k| k.expect_ty()).collect(), @@ -267,6 +150,8 @@ pub(in super::super) fn check_argument_types( (arg_types.iter().map(|k| k.expect_ty()).collect(), expected_input_tys) } _ => { + // Otherwise, there's a mismatch, so clear out what we're expecting, and set + // our input typs to err_args so we don't blow up the error messages struct_span_err!( tcx.sess, call_span, @@ -284,7 +169,7 @@ pub(in super::super) fn check_argument_types( if supplied_arg_count >= expected_arg_count { (formal_input_tys.to_vec(), expected_input_tys) } else { - param_count_error(expected_arg_count, supplied_arg_count, "E0060", true, false); + error = Some((expected_arg_count, supplied_arg_count, "E0060", false)); (self.err_args(supplied_arg_count), vec![]) } } else { @@ -296,8 +181,7 @@ pub(in super::super) fn check_argument_types( } else { false }; - param_count_error(expected_arg_count, supplied_arg_count, "E0061", false, sugg_unit); - + error = Some((expected_arg_count, supplied_arg_count, "E0061", sugg_unit)); (self.err_args(supplied_arg_count), vec![]) }; @@ -348,7 +232,7 @@ pub(in super::super) fn check_argument_types( // argument and not the call. This is otherwise redundant with the `demand_coerce` // call immediately after, but it lets us customize the span pointed to in the // fulfillment error to be more accurate. - let _ = + let coerced_ty = self.resolve_vars_with_obligations_and_mutate_fulfillment(coerced_ty, |errors| { self.point_at_type_arg_instead_of_call_if_possible(errors, call_expr); self.point_at_arg_instead_of_call_if_possible( @@ -360,6 +244,8 @@ pub(in super::super) fn check_argument_types( ); }); + final_arg_types[idx] = Some((checked_ty, coerced_ty)); + // We're processing function arguments so we definitely want to use // two-phase borrows. self.demand_coerce(&provided_arg, checked_ty, coerced_ty, None, AllowTwoPhase::Yes); @@ -418,6 +304,123 @@ pub(in super::super) fn check_argument_types( } } + // If there was an error in parameter count, emit that here + if let Some((expected_count, arg_count, err_code, sugg_unit)) = error { + let (span, start_span, args, ctor_of) = match &call_expr.kind { + hir::ExprKind::Call( + hir::Expr { + span, + kind: + hir::ExprKind::Path(hir::QPath::Resolved( + _, + hir::Path { res: Res::Def(DefKind::Ctor(of, _), _), .. }, + )), + .. + }, + args, + ) => (*span, *span, &args[..], Some(of)), + hir::ExprKind::Call(hir::Expr { span, .. }, args) => { + (*span, *span, &args[..], None) + } + hir::ExprKind::MethodCall(path_segment, args, _) => ( + path_segment.ident.span, + // `sp` doesn't point at the whole `foo.bar()`, only at `bar`. + path_segment + .args + .and_then(|args| args.args.iter().last()) + // Account for `foo.bar::()`. + .map(|arg| { + // Skip the closing `>`. + tcx.sess + .source_map() + .next_point(tcx.sess.source_map().next_point(arg.span())) + }) + .unwrap_or(path_segment.ident.span), + &args[1..], // Skip the receiver. + None, // methods are never ctors + ), + k => span_bug!(call_span, "checking argument types on a non-call: `{:?}`", k), + }; + let arg_spans = if provided_args.is_empty() { + // foo() + // ^^^-- supplied 0 arguments + // | + // expected 2 arguments + vec![tcx.sess.source_map().next_point(start_span).with_hi(call_span.hi())] + } else { + // foo(1, 2, 3) + // ^^^ - - - supplied 3 arguments + // | + // expected 2 arguments + args.iter().map(|arg| arg.span).collect::>() + }; + let call_name = match ctor_of { + Some(CtorOf::Struct) => "struct", + Some(CtorOf::Variant) => "enum variant", + None => "function", + }; + let mut err = tcx.sess.struct_span_err_with_code( + span, + &format!( + "this {} takes {}{} but {} {} supplied", + call_name, + if c_variadic { "at least " } else { "" }, + potentially_plural_count(expected_count, "argument"), + potentially_plural_count(arg_count, "argument"), + if arg_count == 1 { "was" } else { "were" } + ), + DiagnosticId::Error(err_code.to_owned()), + ); + let label = format!("supplied {}", potentially_plural_count(arg_count, "argument")); + for (i, span) in arg_spans.into_iter().enumerate() { + err.span_label( + span, + if arg_count == 0 || i + 1 == arg_count { &label } else { "" }, + ); + } + if let Some(def_id) = fn_def_id { + if let Some(def_span) = tcx.def_ident_span(def_id) { + let mut spans: MultiSpan = def_span.into(); + + let params = tcx + .hir() + .get_if_local(def_id) + .and_then(|node| node.body_id()) + .into_iter() + .map(|id| tcx.hir().body(id).params) + .flatten(); + + for param in params { + spans.push_span_label(param.span, String::new()); + } + + let def_kind = tcx.def_kind(def_id); + err.span_note(spans, &format!("{} defined here", def_kind.descr(def_id))); + } + } + if sugg_unit { + let sugg_span = tcx.sess.source_map().end_point(call_expr.span); + // remove closing `)` from the span + let sugg_span = sugg_span.shrink_to_lo(); + err.span_suggestion( + sugg_span, + "expected the unit value `()`; create it with empty parentheses", + String::from("()"), + Applicability::MachineApplicable, + ); + } else { + err.span_label( + span, + format!( + "expected {}{}", + if c_variadic { "at least " } else { "" }, + potentially_plural_count(expected_count, "argument") + ), + ); + } + err.emit(); + } + // We also need to make sure we at least write the ty of the other // arguments which we skipped above. if c_variadic { diff --git a/src/test/ui/mismatched_types/overloaded-calls-bad.rs b/src/test/ui/mismatched_types/overloaded-calls-bad.rs index 902a6ec81d6..d62625faaaa 100644 --- a/src/test/ui/mismatched_types/overloaded-calls-bad.rs +++ b/src/test/ui/mismatched_types/overloaded-calls-bad.rs @@ -30,4 +30,5 @@ fn main() { //~^ ERROR this function takes 1 argument but 0 arguments were supplied let ans = s("burma", "shave"); //~^ ERROR this function takes 1 argument but 2 arguments were supplied + //~| ERROR mismatched types } diff --git a/src/test/ui/mismatched_types/overloaded-calls-bad.stderr b/src/test/ui/mismatched_types/overloaded-calls-bad.stderr index 264d7cbb9b1..9ae9c474162 100644 --- a/src/test/ui/mismatched_types/overloaded-calls-bad.stderr +++ b/src/test/ui/mismatched_types/overloaded-calls-bad.stderr @@ -18,6 +18,12 @@ note: associated function defined here LL | extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output; | ^^^^^^^^ +error[E0308]: mismatched types + --> $DIR/overloaded-calls-bad.rs:31:17 + | +LL | let ans = s("burma", "shave"); + | ^^^^^^^ expected `isize`, found `&str` + error[E0057]: this function takes 1 argument but 2 arguments were supplied --> $DIR/overloaded-calls-bad.rs:31:15 | @@ -32,7 +38,7 @@ note: associated function defined here LL | extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output; | ^^^^^^^^ -error: aborting due to 3 previous errors +error: aborting due to 4 previous errors Some errors have detailed explanations: E0057, E0308. For more information about an error, try `rustc --explain E0057`.