Remove logic duplication

Author: estebank

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -380,61 +380,46 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 let typeck = self.infcx.tcx.typeck(self.mir_def_id());
                 let hir_id = hir.get_parent_node(expr.hir_id);
                 if let Some(parent) = hir.find(hir_id) {
-                    if let hir::Node::Expr(parent_expr) = parent
+                    let (def_id, args, offset) = if let hir::Node::Expr(parent_expr) = parent
                         && let hir::ExprKind::MethodCall(_, _, args, _) = parent_expr.kind
                         && let Some(def_id) = typeck.type_dependent_def_id(parent_expr.hir_id)
-                        && let Some(def_id) = def_id.as_local()
-                        && let Some(node) = hir.find(hir.local_def_id_to_hir_id(def_id))
-                        && let Some(fn_sig) = node.fn_sig()
-                        && let Some(ident) = node.ident()
-                        && let Some(pos) = args.iter()
-                            .position(|arg| arg.hir_id == expr.hir_id)
-                        && let Some(arg) = fn_sig.decl.inputs.get(pos + 1)
                     {
-                        let mut span: MultiSpan = arg.span.into();
-                        span.push_span_label(
-                            arg.span,
-                            "this type parameter takes ownership of the value".to_string(),
-                        );
-                        span.push_span_label(
-                            ident.span,
-                            "in this method".to_string(),
-                        );
-                        err.span_note(
-                            span,
-                            format!(
-                                "consider changing this parameter type in `{}` to borrow instead \
-                                 if ownering the value isn't necessary",
-                                ident,
-                            ),
-                        );
-                    }
-                    if let hir::Node::Expr(parent_expr) = parent
+                        (def_id.as_local(), args, 1)
+                    } else if let hir::Node::Expr(parent_expr) = parent
                         && let hir::ExprKind::Call(call, args) = parent_expr.kind
                         && let ty::FnDef(def_id, _) = typeck.node_type(call.hir_id).kind()
-                        && let Some(def_id) = def_id.as_local()
+                    {
+                        (def_id.as_local(), args, 0)
+                    } else {
+                        (None, &[][..], 0)
+                    };
+                    if let Some(def_id) = def_id
                         && let Some(node) = hir.find(hir.local_def_id_to_hir_id(def_id))
                         && let Some(fn_sig) = node.fn_sig()
                         && let Some(ident) = node.ident()
                         && let Some(pos) = args.iter()
                             .position(|arg| arg.hir_id == expr.hir_id)
-                        && let Some(arg) = fn_sig.decl.inputs.get(pos)
+                        && let Some(arg) = fn_sig.decl.inputs.get(pos + offset)
                     {
                         let mut span: MultiSpan = arg.span.into();
                         span.push_span_label(
                             arg.span,
                             "this type parameter takes ownership of the value".to_string(),
                         );
+                        let descr = match node.fn_kind() {
+                            Some(hir::intravisit::FnKind::ItemFn(..)) | None => "function",
+                            Some(hir::intravisit::FnKind::Method(..)) => "method",
+                            Some(hir::intravisit::FnKind::Closure) => "closure",
+                        };
                         span.push_span_label(
                             ident.span,
-                            "in this function".to_string(),
+                            format!("in this {descr}"),
                         );
                         err.span_note(
                             span,
                             format!(
-                                "consider changing this parameter type in `{}` to borrow instead \
-                                 if ownering the value isn't necessary",
-                                ident,
+                                "consider changing this parameter type in {descr} `{ident}` to \
+                                 borrow instead if ownering the value isn't necessary",
                             ),
                         );
                     }

src/test/ui/borrowck/borrowck-consume-unsize-vec.stderr

@@ -8,7 +8,7 @@ LL |     consume(b);
 LL |     consume(b);
    |             ^ value used here after move
    |
-note: consider changing this parameter type in `consume` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `consume` to borrow instead if ownering the value isn't necessary
   --> $DIR/borrowck-consume-unsize-vec.rs:3:15
    |
 LL | fn consume(_: Box<[i32]>) {

src/test/ui/borrowck/borrowck-consume-upcast-box.stderr

@@ -8,7 +8,7 @@ LL |     consume(b);
 LL |     consume(b);
    |             ^ value used here after move
    |
-note: consider changing this parameter type in `consume` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `consume` to borrow instead if ownering the value isn't necessary
   --> $DIR/borrowck-consume-upcast-box.rs:5:15
    |
 LL | fn consume(_: Box<dyn Foo>) {

src/test/ui/borrowck/mut-borrow-in-loop-2.stderr

@@ -8,7 +8,7 @@ LL |     for _ in 0..3 {
 LL |         Other::handle(value);
    |                       ^^^^^ value moved here, in previous iteration of loop
    |
-note: consider changing this parameter type in `handle` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `handle` to borrow instead if ownering the value isn't necessary
   --> $DIR/mut-borrow-in-loop-2.rs:9:22
    |
 LL |     fn handle(value: T) -> Self;

src/test/ui/liveness/liveness-move-call-arg.stderr

@@ -9,7 +9,7 @@ LL |     loop {
 LL |         take(x);
    |              ^ value moved here, in previous iteration of loop
    |
-note: consider changing this parameter type in `take` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `take` to borrow instead if ownering the value isn't necessary
   --> $DIR/liveness-move-call-arg.rs:1:13
    |
 LL | fn take(_x: Box<isize>) {}

src/test/ui/liveness/liveness-use-after-send.stderr

@@ -8,7 +8,7 @@ LL |     send(ch, message);
 LL |     println!("{}", message);
    |                    ^^^^^^^ value borrowed here after move
    |
-note: consider changing this parameter type in `send` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `send` to borrow instead if ownering the value isn't necessary
   --> $DIR/liveness-use-after-send.rs:3:54
    |
 LL | fn send<T:Send + std::fmt::Debug>(ch: Chan<T>, data: T) {

src/test/ui/moves/borrow-closures-instead-of-move.stderr

@@ -8,7 +8,7 @@ LL |     loop {
 LL |         takes_fnonce(f);
    |                      ^ value moved here, in previous iteration of loop
    |
-note: consider changing this parameter type in `takes_fnonce` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `takes_fnonce` to borrow instead if ownering the value isn't necessary
   --> $DIR/borrow-closures-instead-of-move.rs:34:20
    |
 LL | fn takes_fnonce(_: impl FnOnce()) {}
@@ -32,7 +32,7 @@ LL |         takes_fnonce(m);
 LL |     takes_fnonce(m);
    |                  ^ value used here after move
    |
-note: consider changing this parameter type in `takes_fnonce` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `takes_fnonce` to borrow instead if ownering the value isn't necessary
   --> $DIR/borrow-closures-instead-of-move.rs:34:20
    |
 LL | fn takes_fnonce(_: impl FnOnce()) {}
@@ -58,7 +58,7 @@ note: closure cannot be moved more than once as it is not `Copy` due to moving t
    |
 LL |         x += 1;
    |         ^
-note: consider changing this parameter type in `takes_fnonce` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `takes_fnonce` to borrow instead if ownering the value isn't necessary
   --> $DIR/borrow-closures-instead-of-move.rs:34:20
    |
 LL | fn takes_fnonce(_: impl FnOnce()) {}

src/test/ui/moves/move-guard-same-consts.stderr

@@ -9,7 +9,7 @@ LL |         (1, 2) if take(x) => (),
 LL |         (1, 2) if take(x) => (),
    |                        ^ value used here after move
    |
-note: consider changing this parameter type in `take` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `take` to borrow instead if ownering the value isn't necessary
   --> $DIR/move-guard-same-consts.rs:25:15
    |
 LL | fn take<T>(_: T) -> bool { false }

src/test/ui/moves/move-in-guard-1.stderr

@@ -9,7 +9,7 @@ LL |         (1, _) if take(x) => (),
 LL |         (_, 2) if take(x) => (),
    |                        ^ value used here after move
    |
-note: consider changing this parameter type in `take` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `take` to borrow instead if ownering the value isn't necessary
   --> $DIR/move-in-guard-1.rs:15:15
    |
 LL | fn take<T>(_: T) -> bool { false }

src/test/ui/moves/move-in-guard-2.stderr

@@ -7,7 +7,7 @@ LL |     let x: Box<_> = Box::new(1);
 LL |         (_, 2) if take(x) => (),
    |                        ^ value used here after move
    |
-note: consider changing this parameter type in `take` to borrow instead if ownering the value isn't necessary
+note: consider changing this parameter type in function `take` to borrow instead if ownering the value isn't necessary
   --> $DIR/move-in-guard-2.rs:13:15
    |
 LL | fn take<T>(_: T) -> bool { false }