Rollup merge of rust-lang#104156 - oli-obk:autoderef, r=estebank

Cleanups in autoderef impl

Just something I noticed. Turns out the `overloaded_span` is not actually used separately from the main span, so I merged them.

Author: Manishearth

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -1708,8 +1708,7 @@ fn receiver_is_valid<'tcx>(
         return true;
     }
 
-    let mut autoderef =
-        Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty, span);
+    let mut autoderef = Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty);
 
     // The `arbitrary_self_types` feature allows raw pointer receivers like `self: *const Self`.
     if arbitrary_self_types_enabled {

compiler/rustc_hir_typeck/src/autoderef.rs

@@ -12,18 +12,7 @@ use std::iter;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn autoderef(&'a self, span: Span, base_ty: Ty<'tcx>) -> Autoderef<'a, 'tcx> {
-        Autoderef::new(self, self.param_env, self.body_id, span, base_ty, span)
-    }
-
-    /// Like `autoderef`, but provides a custom `Span` to use for calls to
-    /// an overloaded `Deref` operator
-    pub fn autoderef_overloaded_span(
-        &'a self,
-        span: Span,
-        base_ty: Ty<'tcx>,
-        overloaded_span: Span,
-    ) -> Autoderef<'a, 'tcx> {
-        Autoderef::new(self, self.param_env, self.body_id, span, base_ty, overloaded_span)
+        Autoderef::new(self, self.param_env, self.body_id, span, base_ty)
     }
 
     pub fn try_overloaded_deref(
@@ -55,11 +44,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         |InferOk { value: method, obligations: o }| {
                             obligations.extend(o);
                             if let ty::Ref(region, _, mutbl) = *method.sig.output().kind() {
-                                Some(OverloadedDeref {
-                                    region,
-                                    mutbl,
-                                    span: autoderef.overloaded_span(),
-                                })
+                                Some(OverloadedDeref { region, mutbl, span: autoderef.span() })
                             } else {
                                 None
                             }

compiler/rustc_hir_typeck/src/method/confirm.rs

@@ -151,8 +151,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
     ) -> Ty<'tcx> {
         // Commit the autoderefs by calling `autoderef` again, but this
         // time writing the results into the various typeck results.
-        let mut autoderef =
-            self.autoderef_overloaded_span(self.span, unadjusted_self_ty, self.call_expr.span);
+        let mut autoderef = self.autoderef(self.call_expr.span, unadjusted_self_ty);
         let Some((ty, n)) = autoderef.nth(pick.autoderefs) else {
             return self.tcx.ty_error_with_message(
                 rustc_span::DUMMY_SP,

compiler/rustc_hir_typeck/src/method/probe.rs

@@ -475,10 +475,9 @@ fn method_autoderef_steps<'tcx>(
     let (ref infcx, goal, inference_vars) = tcx.infer_ctxt().build_with_canonical(DUMMY_SP, &goal);
     let ParamEnvAnd { param_env, value: self_ty } = goal;
 
-    let mut autoderef =
-        Autoderef::new(infcx, param_env, hir::CRATE_HIR_ID, DUMMY_SP, self_ty, DUMMY_SP)
-            .include_raw_pointers()
-            .silence_errors();
+    let mut autoderef = Autoderef::new(infcx, param_env, hir::CRATE_HIR_ID, DUMMY_SP, self_ty)
+        .include_raw_pointers()
+        .silence_errors();
     let mut reached_raw_pointer = false;
     let mut steps: Vec<_> = autoderef
         .by_ref()

compiler/rustc_hir_typeck/src/pat.rs

@@ -19,7 +19,6 @@ use rustc_span::lev_distance::find_best_match_for_name;
 use rustc_span::source_map::{Span, Spanned};
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{BytePos, DUMMY_SP};
-use rustc_trait_selection::autoderef::Autoderef;
 use rustc_trait_selection::traits::{ObligationCause, Pattern};
 use ty::VariantDef;
 
@@ -2132,7 +2131,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             && let ty::Array(..) | ty::Slice(..) = ty.kind()
         {
             err.help("the semantics of slice patterns changed recently; see issue #62254");
-        } else if Autoderef::new(&self.infcx, self.param_env, self.body_id, span, expected_ty, span)
+        } else if self.autoderef(span, expected_ty)
             .any(|(ty, _)| matches!(ty.kind(), ty::Slice(..) | ty::Array(..)))
             && let (Some(span), true) = (ti.span, ti.origin_expr)
             && let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span)

compiler/rustc_trait_selection/src/autoderef.rs

@@ -27,7 +27,6 @@ pub struct Autoderef<'a, 'tcx> {
     // Meta infos:
     infcx: &'a InferCtxt<'tcx>,
     span: Span,
-    overloaded_span: Span,
     body_id: hir::HirId,
     param_env: ty::ParamEnv<'tcx>,
 
@@ -99,12 +98,10 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
         body_id: hir::HirId,
         span: Span,
         base_ty: Ty<'tcx>,
-        overloaded_span: Span,
     ) -> Autoderef<'a, 'tcx> {
         Autoderef {
             infcx,
             span,
-            overloaded_span,
             body_id,
             param_env,
             state: AutoderefSnapshot {
@@ -193,10 +190,6 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
         self.span
     }
 
-    pub fn overloaded_span(&self) -> Span {
-        self.overloaded_span
-    }
-
     pub fn reached_recursion_limit(&self) -> bool {
         self.state.reached_recursion_limit
     }

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -714,7 +714,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     obligation.cause.body_id,
                     span,
                     base_ty,
-                    span,
                 );
                 if let Some(steps) = autoderef.find_map(|(ty, steps)| {
                     // Re-add the `&`