Add a query for CapturedPlace::to_symbol

compiler/rustc_middle/src/ty/closure.rs

@@ -162,7 +162,7 @@ impl CapturedPlace<'tcx> {
     }
 
     /// Returns a symbol of the captured upvar, which looks like `name__field1__field2`.
-    pub fn to_symbol(&self, tcx: TyCtxt<'tcx>) -> Symbol {
+    fn to_symbol(&self, tcx: TyCtxt<'tcx>) -> Symbol {
         let hir_id = match self.place.base {
             HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
             base => bug!("Expected an upvar, found {:?}", base),
@@ -248,6 +248,15 @@ impl CapturedPlace<'tcx> {
     }
 }
 
+fn symbols_for_closure_captures<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    def_id: (LocalDefId, DefId),
+) -> Vec<Symbol> {
+    let typeck_results = tcx.typeck(def_id.0);
+    let captures = typeck_results.closure_min_captures_flattened(def_id.1);
+    captures.into_iter().map(|captured_place| captured_place.to_symbol(tcx)).collect()
+}
+
 /// Return true if the `proj_possible_ancestor` represents an ancestor path
 /// to `proj_capture` or `proj_possible_ancestor` is same as `proj_capture`,
 /// assuming they both start off of the same root variable.
@@ -432,3 +441,7 @@ impl BorrowKind {
         }
     }
 }
+
+pub fn provide(providers: &mut ty::query::Providers) {
+    *providers = ty::query::Providers { symbols_for_closure_captures, ..*providers }
+}

compiler/rustc_middle/src/ty/mod.rs

@@ -16,7 +16,6 @@ pub use self::IntVarValue::*;
 pub use self::Variance::*;
 pub use adt::*;
 pub use assoc::*;
-pub use closure::*;
 pub use generics::*;
 pub use vtable::*;
 
@@ -55,6 +54,12 @@ pub use rustc_type_ir::*;
 
 pub use self::binding::BindingMode;
 pub use self::binding::BindingMode::*;
+pub use self::closure::{
+    is_ancestor_or_same_capture, place_to_string_for_capture, BorrowKind, CaptureInfo,
+    CapturedPlace, ClosureKind, MinCaptureInformationMap, MinCaptureList,
+    RootVariableMinCaptureList, UpvarBorrow, UpvarCapture, UpvarCaptureMap, UpvarId, UpvarListMap,
+    UpvarPath, CAPTURE_STRUCT_LOCAL,
+};
 pub use self::consts::{Const, ConstInt, ConstKind, InferConst, ScalarInt, Unevaluated, ValTree};
 pub use self::context::{
     tls, CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations,
@@ -1979,6 +1984,7 @@ pub fn ast_uint_ty(uty: UintTy) -> ast::UintTy {
 }
 
 pub fn provide(providers: &mut ty::query::Providers) {
+    closure::provide(providers);
     context::provide(providers);
     erase_regions::provide(providers);
     layout::provide(providers);