11#![ feature( array_chunks) ]
22#![ feature( box_patterns) ]
33#![ feature( control_flow_enum) ]
4+ #![ feature( exhaustive_patterns) ]
45#![ feature( if_let_guard) ]
56#![ feature( let_chains) ]
67#![ feature( lint_reasons) ]
@@ -2618,13 +2619,80 @@ pub enum DefinedTy<'tcx> {
26182619/// The context an expressions value is used in.
26192620pub struct ExprUseCtxt < ' tcx > {
26202621 /// The parent node which consumes the value.
2621- pub node : ExprUseNode < ' tcx > ,
2622+ pub node : Node < ' tcx > ,
2623+ /// The child id of the node the value came from.
2624+ pub child_id : HirId ,
26222625 /// Any adjustments applied to the type.
26232626pub adjustments : & ' tcx [ Adjustment < ' tcx > ] ,
2624- /// Whether or not the type must unify with another code path.
2627+ /// Whether the type must unify with another code path.
26252628pub is_ty_unified : bool ,
2626- /// Whether or not the value will be moved before it's used.
2629+ /// Whether the value will be moved before it's used.
26272630pub moved_before_use : bool ,
2631+ /// Whether the use site has the same `SyntaxContext` as the value.
2632+ pub same_ctxt : bool ,
2633+ }
2634+ impl < ' tcx > ExprUseCtxt < ' tcx > {
2635+ pub fn use_node ( & self , cx : & LateContext < ' tcx > ) -> ExprUseNode < ' tcx > {
2636+ match self . node {
2637+ Node :: Local ( l) => ExprUseNode :: Local ( l) ,
2638+ Node :: ExprField ( field) => ExprUseNode :: Field ( field) ,
2639+
2640+ Node :: Item ( & Item {
2641+ kind : ItemKind :: Static ( ..) | ItemKind :: Const ( ..) ,
2642+ owner_id,
2643+ ..
2644+ } )
2645+ | Node :: TraitItem ( & TraitItem {
2646+ kind : TraitItemKind :: Const ( ..) ,
2647+ owner_id,
2648+ ..
2649+ } )
2650+ | Node :: ImplItem ( & ImplItem {
2651+ kind : ImplItemKind :: Const ( ..) ,
2652+ owner_id,
2653+ ..
2654+ } ) => ExprUseNode :: ConstStatic ( owner_id) ,
2655+
2656+ Node :: Item ( & Item {
2657+ kind : ItemKind :: Fn ( ..) ,
2658+ owner_id,
2659+ ..
2660+ } )
2661+ | Node :: TraitItem ( & TraitItem {
2662+ kind : TraitItemKind :: Fn ( ..) ,
2663+ owner_id,
2664+ ..
2665+ } )
2666+ | Node :: ImplItem ( & ImplItem {
2667+ kind : ImplItemKind :: Fn ( ..) ,
2668+ owner_id,
2669+ ..
2670+ } ) => ExprUseNode :: Return ( owner_id) ,
2671+
2672+ Node :: Expr ( use_expr) => match use_expr. kind {
2673+ ExprKind :: Ret ( _) => ExprUseNode :: Return ( OwnerId {
2674+ def_id : cx. tcx . hir ( ) . body_owner_def_id ( cx. enclosing_body . unwrap ( ) ) ,
2675+ } ) ,
2676+
2677+ ExprKind :: Closure ( closure) => ExprUseNode :: Return ( OwnerId { def_id : closure. def_id } ) ,
2678+ ExprKind :: Call ( func, args) => match args. iter ( ) . position ( |arg| arg. hir_id == self . child_id ) {
2679+ Some ( i) => ExprUseNode :: FnArg ( func, i) ,
2680+ None => ExprUseNode :: Callee ,
2681+ } ,
2682+ ExprKind :: MethodCall ( name, _, args, _) => ExprUseNode :: MethodArg (
2683+ use_expr. hir_id ,
2684+ name. args ,
2685+ args. iter ( )
2686+ . position ( |arg| arg. hir_id == self . child_id )
2687+ . map_or ( 0 , |i| i + 1 ) ,
2688+ ) ,
2689+ ExprKind :: Field ( _, name) => ExprUseNode :: FieldAccess ( name) ,
2690+ ExprKind :: AddrOf ( kind, mutbl, _) => ExprUseNode :: AddrOf ( kind, mutbl) ,
2691+ _ => ExprUseNode :: Other ,
2692+ } ,
2693+ _ => ExprUseNode :: Other ,
2694+ }
2695+ }
26282696}
26292697
26302698/// The node which consumes a value.
@@ -2645,7 +2713,8 @@ pub enum ExprUseNode<'tcx> {
26452713Callee ,
26462714 /// Access of a field.
26472715FieldAccess ( Ident ) ,
2648- Expr ,
2716+ /// Borrow expression.
2717+ AddrOf ( ast:: BorrowKind , Mutability ) ,
26492718 Other ,
26502719}
26512720impl < ' tcx > ExprUseNode < ' tcx > {
@@ -2723,25 +2792,26 @@ impl<'tcx> ExprUseNode<'tcx> {
27232792 let sig = cx. tcx . fn_sig ( id) . skip_binder ( ) ;
27242793 Some ( DefinedTy :: Mir ( cx. tcx . param_env ( id) . and ( sig. input ( i) ) ) )
27252794 } ,
2726- Self :: Local ( _) | Self :: FieldAccess ( ..) | Self :: Callee | Self :: Expr | Self :: Other => None ,
2795+ Self :: Local ( _) | Self :: FieldAccess ( ..) | Self :: Callee | Self :: Other | Self :: AddrOf ( .. ) => None ,
27272796 }
27282797 }
27292798}
27302799
27312800/// Gets the context an expression's value is used in.
2732- pub fn expr_use_ctxt < ' tcx > ( cx : & LateContext < ' tcx > , e : & ' tcx Expr < ' tcx > ) -> Option < ExprUseCtxt < ' tcx > > {
2801+ pub fn expr_use_ctxt < ' tcx > ( cx : & LateContext < ' tcx > , e : & ' tcx Expr < ' tcx > ) -> ExprUseCtxt < ' tcx > {
27332802 let mut adjustments = [ ] . as_slice ( ) ;
27342803 let mut is_ty_unified = false ;
27352804 let mut moved_before_use = false ;
2805+ let mut same_ctxt = true ;
27362806 let ctxt = e. span . ctxt ( ) ;
2737- walk_to_expr_usage ( cx, e, & mut |parent_id, parent, child_id| {
2807+ let node = walk_to_expr_usage ( cx, e, & mut |parent_id, parent, child_id| -> ControlFlow < ! > {
27382808 if adjustments. is_empty ( )
27392809 && let Node :: Expr ( e) = cx. tcx . hir_node ( child_id)
27402810 {
27412811 adjustments = cx. typeck_results ( ) . expr_adjustments ( e) ;
27422812 }
2743- if ! cx. tcx . hir ( ) . opt_span ( parent_id) . is_some_and ( |x| x . ctxt ( ) == ctxt ) {
2744- return ControlFlow :: Break ( ( ) ) ;
2813+ if let Some ( s ) = cx. tcx . hir ( ) . opt_span ( parent_id) {
2814+ same_ctxt &= s . ctxt ( ) == ctxt ;
27452815 }
27462816 if let Node :: Expr ( e) = parent {
27472817 match e. kind {
@@ -2758,71 +2828,25 @@ pub fn expr_use_ctxt<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'tcx>) -> Optio
27582828 }
27592829 }
27602830 ControlFlow :: Continue ( ( ) )
2761- } ) ?
2762- . continue_value ( )
2763- . map ( |( use_node, child_id) | {
2764- let node = match use_node {
2765- Node :: Local ( l) => ExprUseNode :: Local ( l) ,
2766- Node :: ExprField ( field) => ExprUseNode :: Field ( field) ,
2767-
2768- Node :: Item ( & Item {
2769- kind : ItemKind :: Static ( ..) | ItemKind :: Const ( ..) ,
2770- owner_id,
2771- ..
2772- } )
2773- | Node :: TraitItem ( & TraitItem {
2774- kind : TraitItemKind :: Const ( ..) ,
2775- owner_id,
2776- ..
2777- } )
2778- | Node :: ImplItem ( & ImplItem {
2779- kind : ImplItemKind :: Const ( ..) ,
2780- owner_id,
2781- ..
2782- } ) => ExprUseNode :: ConstStatic ( owner_id) ,
2783-
2784- Node :: Item ( & Item {
2785- kind : ItemKind :: Fn ( ..) ,
2786- owner_id,
2787- ..
2788- } )
2789- | Node :: TraitItem ( & TraitItem {
2790- kind : TraitItemKind :: Fn ( ..) ,
2791- owner_id,
2792- ..
2793- } )
2794- | Node :: ImplItem ( & ImplItem {
2795- kind : ImplItemKind :: Fn ( ..) ,
2796- owner_id,
2797- ..
2798- } ) => ExprUseNode :: Return ( owner_id) ,
2799-
2800- Node :: Expr ( use_expr) => match use_expr. kind {
2801- ExprKind :: Ret ( _) => ExprUseNode :: Return ( OwnerId {
2802- def_id : cx. tcx . hir ( ) . body_owner_def_id ( cx. enclosing_body . unwrap ( ) ) ,
2803- } ) ,
2804- ExprKind :: Closure ( closure) => ExprUseNode :: Return ( OwnerId { def_id : closure. def_id } ) ,
2805- ExprKind :: Call ( func, args) => match args. iter ( ) . position ( |arg| arg. hir_id == child_id) {
2806- Some ( i) => ExprUseNode :: FnArg ( func, i) ,
2807- None => ExprUseNode :: Callee ,
2808- } ,
2809- ExprKind :: MethodCall ( name, _, args, _) => ExprUseNode :: MethodArg (
2810- use_expr. hir_id ,
2811- name. args ,
2812- args. iter ( ) . position ( |arg| arg. hir_id == child_id) . map_or ( 0 , |i| i + 1 ) ,
2813- ) ,
2814- ExprKind :: Field ( child, name) if child. hir_id == e. hir_id => ExprUseNode :: FieldAccess ( name) ,
2815- _ => ExprUseNode :: Expr ,
2816- } ,
2817- _ => ExprUseNode :: Other ,
2818- } ;
2819- ExprUseCtxt {
2831+ } ) ;
2832+ match node {
2833+ Some ( ControlFlow :: Continue ( ( node, child_id) ) ) => ExprUseCtxt {
28202834 node,
2835+ child_id,
28212836 adjustments,
28222837 is_ty_unified,
28232838 moved_before_use,
2824- }
2825- } )
2839+ same_ctxt,
2840+ } ,
2841+ None => ExprUseCtxt {
2842+ node : Node :: Crate ( cx. tcx . hir ( ) . root_module ( ) ) ,
2843+ child_id : HirId :: INVALID ,
2844+ adjustments : & [ ] ,
2845+ is_ty_unified : true ,
2846+ moved_before_use : true ,
2847+ same_ctxt : false ,
2848+ } ,
2849+ }
28262850}
28272851
28282852/// Tokenizes the input while keeping the text associated with each token.
0 commit comments