Yeet point_at_expr_source_of_inferred_type for now

Author: compiler-errors

compiler/rustc_hir_typeck/src/demand.rs

@@ -1,26 +1,21 @@
 use crate::FnCtxt;
 use rustc_ast::util::parser::PREC_POSTFIX;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::MultiSpan;
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def::CtorKind;
-use rustc_hir::intravisit::Visitor;
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{is_range_literal, Node};
 use rustc_infer::infer::InferOk;
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::middle::stability::EvalResult;
 use rustc_middle::ty::adjustment::AllowTwoPhase;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::fold::{BottomUpFolder, TypeFolder};
-use rustc_middle::ty::print::{with_forced_trimmed_paths, with_no_trimmed_paths};
-use rustc_middle::ty::relate::TypeRelation;
-use rustc_middle::ty::{self, Article, AssocItem, Ty, TypeAndMut, TypeVisitable};
+use rustc_middle::ty::print::with_no_trimmed_paths;
+use rustc_middle::ty::{self, Article, AssocItem, Ty, TypeAndMut};
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{BytePos, Span};
 use rustc_trait_selection::infer::InferCtxtExt as _;
-use rustc_trait_selection::traits::error_reporting::method_chain::CollectAllMismatches;
 use rustc_trait_selection::traits::ObligationCause;
 
 use super::method::probe;
@@ -45,7 +40,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         self.annotate_alternative_method_deref(err, expr, error);
 
         // Use `||` to give these suggestions a precedence
-        let suggested = self.suggest_missing_parentheses(err, expr)
+        let _ = self.suggest_missing_parentheses(err, expr)
             || self.suggest_remove_last_method_call(err, expr, expected)
             || self.suggest_associated_const(err, expr, expected)
             || self.suggest_deref_ref_or_into(err, expr, expected, expr_ty, expected_ty_expr)
@@ -60,9 +55,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             || self.suggest_clone_for_ref(err, expr, expr_ty, expected)
             || self.suggest_into(err, expr, expr_ty, expected)
             || self.suggest_floating_point_literal(err, expr, expected);
-        if !suggested {
-            self.point_at_expr_source_of_inferred_type(err, expr, expr_ty, expected);
-        }
     }
 
     pub fn emit_coerce_suggestions(
@@ -216,216 +208,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         (expected, Some(err))
     }
 
-    pub fn point_at_expr_source_of_inferred_type(
-        &self,
-        err: &mut Diagnostic,
-        expr: &hir::Expr<'_>,
-        found: Ty<'tcx>,
-        expected: Ty<'tcx>,
-    ) -> bool {
-        let map = self.tcx.hir();
-
-        let hir::ExprKind::Path(hir::QPath::Resolved(None, p)) = expr.kind else { return false; };
-        let [hir::PathSegment { ident, args: None, .. }] = p.segments else { return false; };
-        let hir::def::Res::Local(hir_id) = p.res else { return false; };
-        let Some(hir::Node::Pat(pat)) = map.find(hir_id) else { return false; };
-        let Some(hir::Node::Local(hir::Local {
-            ty: None,
-            init: Some(init),
-            ..
-        })) = map.find_parent(pat.hir_id) else { return false; };
-        let Some(ty) = self.node_ty_opt(init.hir_id) else { return false; };
-        if ty.is_closure() || init.span.overlaps(expr.span) || pat.span.from_expansion() {
-            return false;
-        }
-
-        // Locate all the usages of the relevant binding.
-        struct FindExprs<'hir> {
-            hir_id: hir::HirId,
-            uses: Vec<&'hir hir::Expr<'hir>>,
-        }
-        impl<'v> Visitor<'v> for FindExprs<'v> {
-            fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
-                if let hir::ExprKind::Path(hir::QPath::Resolved(None, path)) = ex.kind
-                    && let hir::def::Res::Local(hir_id) = path.res
-                    && hir_id == self.hir_id
-                {
-                    self.uses.push(ex);
-                }
-                hir::intravisit::walk_expr(self, ex);
-            }
-        }
-
-        let mut expr_finder = FindExprs { hir_id, uses: vec![] };
-        let id = map.get_parent_item(hir_id);
-        let hir_id: hir::HirId = id.into();
-
-        let Some(node) = map.find(hir_id) else { return false; };
-        let Some(body_id) = node.body_id() else { return false; };
-        let body = map.body(body_id);
-        expr_finder.visit_expr(body.value);
-        // Hack to make equality checks on types with inference variables and regions useful.
-        let mut eraser = BottomUpFolder {
-            tcx: self.tcx,
-            lt_op: |_| self.tcx.lifetimes.re_erased,
-            ct_op: |c| c,
-            ty_op: |t| match *t.kind() {
-                ty::Infer(ty::TyVar(vid)) => self.tcx.mk_ty_infer(ty::TyVar(self.root_var(vid))),
-                ty::Infer(ty::IntVar(_)) => {
-                    self.tcx.mk_ty_infer(ty::IntVar(ty::IntVid { index: 0 }))
-                }
-                ty::Infer(ty::FloatVar(_)) => {
-                    self.tcx.mk_ty_infer(ty::FloatVar(ty::FloatVid { index: 0 }))
-                }
-                _ => t,
-            },
-        };
-        let mut prev = eraser.fold_ty(ty);
-        let mut prev_span = None;
-
-        for binding in expr_finder.uses {
-            // In every expression where the binding is referenced, we will look at that
-            // expression's type and see if it is where the incorrect found type was fully
-            // "materialized" and point at it. We will also try to provide a suggestion there.
-            if let Some(hir::Node::Expr(expr)
-            | hir::Node::Stmt(hir::Stmt {
-                kind: hir::StmtKind::Expr(expr) | hir::StmtKind::Semi(expr),
-                ..
-            })) = &map.find_parent(binding.hir_id)
-                && let hir::ExprKind::MethodCall(segment, rcvr, args, _span) = expr.kind
-                && rcvr.hir_id == binding.hir_id
-                && let Some(def_id) = self.typeck_results.borrow().type_dependent_def_id(expr.hir_id)
-            {
-                // We special case methods, because they can influence inference through the
-                // call's arguments and we can provide a more explicit span.
-                let sig = self.tcx.fn_sig(def_id);
-                let def_self_ty = sig.input(0).skip_binder();
-                let rcvr_ty = self.node_ty(rcvr.hir_id);
-                // Get the evaluated type *after* calling the method call, so that the influence
-                // of the arguments can be reflected in the receiver type. The receiver
-                // expression has the type *before* theis analysis is done.
-                let ty = match self.lookup_probe_for_diagnostic(
-                    segment.ident,
-                    rcvr_ty,
-                    expr,
-                    probe::ProbeScope::TraitsInScope,
-                    None,
-                ) {
-                    Ok(pick) => pick.self_ty,
-                    Err(_) => rcvr_ty,
-                };
-                // Remove one layer of references to account for `&mut self` and
-                // `&self`, so that we can compare it against the binding.
-                let (ty, def_self_ty) = match (ty.kind(), def_self_ty.kind()) {
-                    (ty::Ref(_, ty, a), ty::Ref(_, self_ty, b)) if a == b => (*ty, *self_ty),
-                    _ => (ty, def_self_ty),
-                };
-                let mut param_args = FxHashMap::default();
-                let mut param_expected = FxHashMap::default();
-                let mut param_found = FxHashMap::default();
-                if self.can_eq(self.param_env, ty, found).is_ok() {
-                    // We only point at the first place where the found type was inferred.
-                    for (i, param_ty) in sig.inputs().skip_binder().iter().skip(1).enumerate() {
-                        if def_self_ty.contains(*param_ty) && let ty::Param(_) = param_ty.kind() {
-                            // We found an argument that references a type parameter in `Self`,
-                            // so we assume that this is the argument that caused the found
-                            // type, which we know already because of `can_eq` above was first
-                            // inferred in this method call.
-                            let arg = &args[i];
-                            let arg_ty = self.node_ty(arg.hir_id);
-                            err.span_label(
-                                arg.span,
-                                &format!(
-                                    "this is of type `{arg_ty}`, which causes `{ident}` to be \
-                                     inferred as `{ty}`",
-                                ),
-                            );
-                            param_args.insert(param_ty, (arg, arg_ty));
-                        }
-                    }
-                }
-
-                // Here we find, for a type param `T`, the type that `T` is in the current
-                // method call *and* in the original expected type. That way, we can see if we
-                // can give any structured suggestion for the function argument.
-                let mut c = CollectAllMismatches {
-                    infcx: &self.infcx,
-                    param_env: self.param_env,
-                    errors: vec![],
-                };
-                let _ = c.relate(def_self_ty, ty);
-                for error in c.errors {
-                    if let TypeError::Sorts(error) = error {
-                        param_found.insert(error.expected, error.found);
-                    }
-                }
-                c.errors = vec![];
-                let _ = c.relate(def_self_ty, expected);
-                for error in c.errors {
-                    if let TypeError::Sorts(error) = error {
-                        param_expected.insert(error.expected, error.found);
-                    }
-                }
-                for (param, (arg, arg_ty)) in param_args.iter() {
-                    let Some(expected) = param_expected.get(param) else { continue; };
-                    let Some(found) = param_found.get(param) else { continue; };
-                    if self.can_eq(self.param_env, *arg_ty, *found).is_err() { continue; }
-                    self.emit_coerce_suggestions(err, arg, *found, *expected, None, None);
-                }
-
-                let ty = eraser.fold_ty(ty);
-                if ty.references_error() {
-                    break;
-                }
-                if ty != prev
-                    && param_args.is_empty()
-                    && self.can_eq(self.param_env, ty, found).is_ok()
-                {
-                    // We only point at the first place where the found type was inferred.
-                    err.span_label(
-                        segment.ident.span,
-                        with_forced_trimmed_paths!(format!(
-                            "here the type of `{ident}` is inferred to be `{ty}`",
-                        )),
-                    );
-                    break;
-                } else if !param_args.is_empty() {
-                    break;
-                }
-                prev = ty;
-            } else {
-                let ty = eraser.fold_ty(self.node_ty(binding.hir_id));
-                if ty.references_error() {
-                    break;
-                }
-                if ty != prev
-                    && let Some(span) = prev_span
-                    && self.can_eq(self.param_env, ty, found).is_ok()
-                {
-                    // We only point at the first place where the found type was inferred.
-                    // We use the *previous* span because if the type is known *here* it means
-                    // it was *evaluated earlier*. We don't do this for method calls because we
-                    // evaluate the method's self type eagerly, but not in any other case.
-                    err.span_label(
-                        span,
-                        with_forced_trimmed_paths!(format!(
-                            "here the type of `{ident}` is inferred to be `{ty}`",
-                        )),
-                    );
-                    break;
-                }
-                prev = ty;
-            }
-            if binding.hir_id == expr.hir_id {
-                // Do not look at expressions that come after the expression we were originally
-                // evaluating and had a type error.
-                break;
-            }
-            prev_span = Some(binding.span);
-        }
-        true
-    }
-
     fn annotate_expected_due_to_let_ty(
         &self,
         err: &mut Diagnostic,

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -798,18 +798,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 full_call_span,
                 format!("arguments to this {} are incorrect", call_name),
             );
-            if let (Some(callee_ty), hir::ExprKind::MethodCall(_, rcvr, _, _)) =
-                (callee_ty, &call_expr.kind)
-            {
-                // Type that would have accepted this argument if it hadn't been inferred earlier.
-                // FIXME: We leave an inference variable for now, but it'd be nice to get a more
-                // specific type to increase the accuracy of the diagnostic.
-                let expected = self.infcx.next_ty_var(TypeVariableOrigin {
-                    kind: TypeVariableOriginKind::MiscVariable,
-                    span: full_call_span,
-                });
-                self.point_at_expr_source_of_inferred_type(&mut err, rcvr, expected, callee_ty);
-            }
             // Call out where the function is defined
             self.label_fn_like(
                 &mut err,

tests/ui/type/type-check/assignment-in-if.stderr

@@ -67,9 +67,6 @@ LL |             x == 5
 error[E0308]: mismatched types
   --> $DIR/assignment-in-if.rs:44:18
    |
-LL |     if y = (Foo { foo: x }) {
-   |                        - here the type of `x` is inferred to be `usize`
-...
 LL |     if x == x && x = x && x == x {
    |        ------    ^ expected `bool`, found `usize`
    |        |
@@ -78,9 +75,6 @@ LL |     if x == x && x = x && x == x {
 error[E0308]: mismatched types
   --> $DIR/assignment-in-if.rs:44:22
    |
-LL |     if y = (Foo { foo: x }) {
-   |                        - here the type of `x` is inferred to be `usize`
-...
 LL |     if x == x && x = x && x == x {
    |                      ^ expected `bool`, found `usize`
 
@@ -98,9 +92,6 @@ LL |     if x == x && x == x && x == x {
 error[E0308]: mismatched types
   --> $DIR/assignment-in-if.rs:51:28
    |
-LL |     if y = (Foo { foo: x }) {
-   |                        - here the type of `x` is inferred to be `usize`
-...
 LL |     if x == x && x == x && x = x {
    |        ----------------    ^ expected `bool`, found `usize`
    |        |

tests/ui/type/type-check/point-at-inference-2.stderr

@@ -17,9 +17,6 @@ LL | fn bar(_: Vec<i32>) {}
 error[E0308]: mismatched types
   --> $DIR/point-at-inference-2.rs:9:9
    |
-LL |     baz(&v);
-   |          - here the type of `v` is inferred to be `Vec<&i32>`
-LL |     baz(&v);
 LL |     bar(v);
    |     --- ^ expected `i32`, found `&i32`
    |     |
@@ -36,8 +33,6 @@ LL | fn bar(_: Vec<i32>) {}
 error[E0308]: mismatched types
   --> $DIR/point-at-inference-2.rs:12:9
    |
-LL |     baz(&v);
-   |          - here the type of `v` is inferred to be `Vec<&i32>`
 LL |     bar(v);
    |     --- ^ expected `i32`, found `&i32`
    |     |

tests/ui/type/type-check/point-at-inference-3.fixed

@@ -2,7 +2,6 @@
 fn main() {
     let mut v = Vec::new();
     v.push(0i32);
-    //~^ NOTE this is of type `i32`, which causes `v` to be inferred as `Vec<i32>`
     v.push(0);
     v.push(1i32); //~ ERROR mismatched types
     //~^ NOTE expected `i32`, found `u32`

tests/ui/type/type-check/point-at-inference-3.rs

@@ -2,7 +2,6 @@
 fn main() {
     let mut v = Vec::new();
     v.push(0i32);
-    //~^ NOTE this is of type `i32`, which causes `v` to be inferred as `Vec<i32>`
     v.push(0);
     v.push(1u32); //~ ERROR mismatched types
     //~^ NOTE expected `i32`, found `u32`

tests/ui/type/type-check/point-at-inference-3.stderr

@@ -1,9 +1,6 @@
 error[E0308]: mismatched types
-  --> $DIR/point-at-inference-3.rs:7:12
+  --> $DIR/point-at-inference-3.rs:6:12
    |
-LL |     v.push(0i32);
-   |            ---- this is of type `i32`, which causes `v` to be inferred as `Vec<i32>`
-...
 LL |     v.push(1u32);
    |       ---- ^^^^ expected `i32`, found `u32`
    |       |

tests/ui/type/type-check/point-at-inference.fixed

@@ -1,4 +1,3 @@
-// run-rustfix
 fn bar(_: Vec<i32>) {}
 fn baz(_: &impl std::any::Any) {}
 fn main() {