Clarify what "this" means

Author: oli-obk

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -1069,7 +1069,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         );
                     }
                 }
-                CallKind::Normal { self_arg, desugaring, is_option_or_result } => {
+                CallKind::Normal { self_arg, desugaring, method_did } => {
                     let self_arg = self_arg.unwrap();
                     if let Some((CallDesugaringKind::ForLoopIntoIter, _)) = desugaring {
                         let ty = moved_place.ty(self.body, self.infcx.tcx).ty;
@@ -1139,14 +1139,27 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             ),
                         );
                     }
+                    let tcx = self.infcx.tcx;
                     // Avoid pointing to the same function in multiple different
                     // error messages.
                     if span != DUMMY_SP && self.fn_self_span_reported.insert(self_arg.span) {
+                        let func = tcx.def_path_str(method_did);
                         err.span_note(
                             self_arg.span,
-                            &format!("this function takes ownership of the receiver `self`, which moves {}", place_name)
+                            &format!("`{func}` takes ownership of the receiver `self`, which moves {place_name}")
                         );
                     }
+                    let parent_did = tcx.parent(method_did);
+                    let parent_self_ty = (tcx.def_kind(parent_did)
+                        == rustc_hir::def::DefKind::Impl)
+                        .then_some(parent_did)
+                        .and_then(|did| match tcx.type_of(did).kind() {
+                            ty::Adt(def, ..) => Some(def.did()),
+                            _ => None,
+                        });
+                    let is_option_or_result = parent_self_ty.map_or(false, |def_id| {
+                        matches!(tcx.get_diagnostic_name(def_id), Some(sym::Option | sym::Result))
+                    });
                     if is_option_or_result && maybe_reinitialized_locations_is_empty {
                         err.span_label(
                             var_span,

compiler/rustc_const_eval/src/util/call_kind.rs

@@ -5,7 +5,7 @@
 use rustc_hir::def_id::DefId;
 use rustc_hir::{lang_items, LangItem};
 use rustc_middle::ty::subst::SubstsRef;
-use rustc_middle::ty::{self, AssocItemContainer, DefIdTree, Instance, ParamEnv, Ty, TyCtxt};
+use rustc_middle::ty::{AssocItemContainer, Instance, ParamEnv, Ty, TyCtxt};
 use rustc_span::symbol::Ident;
 use rustc_span::{sym, DesugaringKind, Span};
 
@@ -39,9 +39,7 @@ pub enum CallKind<'tcx> {
     Normal {
         self_arg: Option<Ident>,
         desugaring: Option<(CallDesugaringKind, Ty<'tcx>)>,
-        /// Whether the self type of the method call has an `.as_ref()` method.
-        /// Used for better diagnostics.
-        is_option_or_result: bool,
+        method_did: DefId,
     },
     /// A call to `Fn(..)::call(..)`, desugared from `my_closure(a, b, c)`
     FnCall { fn_trait_id: DefId, self_ty: Ty<'tcx> },
@@ -133,16 +131,6 @@ pub fn call_kind<'tcx>(
         } else {
             None
         };
-        let parent_did = tcx.parent(method_did);
-        let parent_self_ty = (tcx.def_kind(parent_did) == rustc_hir::def::DefKind::Impl)
-            .then_some(parent_did)
-            .and_then(|did| match tcx.type_of(did).kind() {
-                ty::Adt(def, ..) => Some(def.did()),
-                _ => None,
-            });
-        let is_option_or_result = parent_self_ty.map_or(false, |def_id| {
-            matches!(tcx.get_diagnostic_name(def_id), Some(sym::Option | sym::Result))
-        });
-        CallKind::Normal { self_arg, desugaring, is_option_or_result }
+        CallKind::Normal { self_arg, desugaring, method_did }
     })
 }

src/test/ui/borrowck/borrowck-move-out-of-overloaded-auto-deref.stderr

@@ -7,7 +7,7 @@ LL |     let _x = Rc::new(vec![1, 2]).into_iter();
    |              |                   value moved due to this method call
    |              move occurs because value has type `Vec<i32>`, which does not implement the `Copy` trait
    |
-note: this function takes ownership of the receiver `self`, which moves value
+note: `into_iter` takes ownership of the receiver `self`, which moves value
   --> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
 
 error: aborting due to previous error

src/test/ui/borrowck/issue-83760.stderr

@@ -27,7 +27,7 @@ LL |         foo = Some(Struct);
 LL |     let _y = foo;
    |              ^^^ value used here after move
    |
-note: this function takes ownership of the receiver `self`, which moves `foo`
+note: `Option::<T>::unwrap` takes ownership of the receiver `self`, which moves `foo`
   --> $SRC_DIR/core/src/option.rs:LL:COL
 
 error[E0382]: use of moved value: `foo`
@@ -52,7 +52,7 @@ LL |         foo = Some(Struct);
 LL |     } else if true {
 LL |         foo = Some(Struct);
    |         ^^^^^^^^^^^^^^^^^^
-note: this function takes ownership of the receiver `self`, which moves `foo`
+note: `Option::<T>::unwrap` takes ownership of the receiver `self`, which moves `foo`
   --> $SRC_DIR/core/src/option.rs:LL:COL
 
 error: aborting due to 3 previous errors

src/test/ui/borrowck/reborrow-sugg-move-then-borrow.stderr

@@ -9,7 +9,7 @@ LL |
 LL |     fill_segment(state);
    |                  ^^^^^ value borrowed here after move
    |
-note: this function takes ownership of the receiver `self`, which moves `state`
+note: `into_iter` takes ownership of the receiver `self`, which moves `state`
   --> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
 help: consider creating a fresh reborrow of `state` here
    |

src/test/ui/borrowck/suggest-as-ref-on-mut-closure.stderr

@@ -8,7 +8,7 @@ LL |     cb.map(|cb| cb());
    |     help: consider calling `.as_ref()` or `.as_mut()` to borrow the type's contents
    |     move occurs because `*cb` has type `Option<&mut dyn FnMut()>`, which does not implement the `Copy` trait
    |
-note: this function takes ownership of the receiver `self`, which moves `*cb`
+note: `Option::<T>::map` takes ownership of the receiver `self`, which moves `*cb`
   --> $SRC_DIR/core/src/option.rs:LL:COL
 
 error[E0596]: cannot borrow `*cb` as mutable, as it is behind a `&` reference

src/test/ui/borrowck/unboxed-closures-move-upvar-from-non-once-ref-closure.stderr

@@ -10,7 +10,7 @@ LL |         y.into_iter();
    |         |
    |         move occurs because `y` has type `Vec<String>`, which does not implement the `Copy` trait
    |
-note: this function takes ownership of the receiver `self`, which moves `y`
+note: `into_iter` takes ownership of the receiver `self`, which moves `y`
   --> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
 
 error: aborting due to previous error

src/test/ui/codemap_tests/tab_3.stderr

@@ -9,7 +9,7 @@ LL |     {
 LL |         println!("{:?}", some_vec);
    |                          ^^^^^^^^ value borrowed here after move
    |
-note: this function takes ownership of the receiver `self`, which moves `some_vec`
+note: `into_iter` takes ownership of the receiver `self`, which moves `some_vec`
   --> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider cloning the value if the performance cost is acceptable

src/test/ui/error-codes/E0507.stderr

@@ -7,7 +7,7 @@ LL |     x.borrow().nothing_is_true();
    |     |          value moved due to this method call
    |     move occurs because value has type `TheDarkKnight`, which does not implement the `Copy` trait
    |
-note: this function takes ownership of the receiver `self`, which moves value
+note: `TheDarkKnight::nothing_is_true` takes ownership of the receiver `self`, which moves value
   --> $DIR/E0507.rs:6:24
    |
 LL |     fn nothing_is_true(self) {}

src/test/ui/issues/issue-34721.stderr

@@ -13,7 +13,7 @@ LL |         };
 LL |         x.zero()
    |         ^ value used here after move
    |
-note: this function takes ownership of the receiver `self`, which moves `x`
+note: `Foo::zero` takes ownership of the receiver `self`, which moves `x`
   --> $DIR/issue-34721.rs:4:13
    |
 LL |     fn zero(self) -> Self;