Rollup merge of #81318 - CraftSpider:json-trait-fix, r=jyn514

[rust.git] / compiler / rustc_middle / src / ty / mod.rs

diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index ddb78d91759f94e4f2bcf23128194f3002f8279b..babab005edb2b3a85c7dd53644b012b00635069a 100644 (file)
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -674,6 +674,17 @@ pub struct CapturedPlace<'tcx> {
     pub mutability: hir::Mutability,
 }
 
+impl CapturedPlace<'tcx> {
+    /// Returns the hir-id of the root variable for the captured place.
+    /// e.g., if `a.b.c` was captured, would return the hir-id for `a`.
+    pub fn get_root_variable(&self) -> hir::HirId {
+        match self.place.base {
+            HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
+            base => bug!("Expected upvar, found={:?}", base),
+        }
+    }
+}
+
 pub fn place_to_string_for_capture(tcx: TyCtxt<'tcx>, place: &HirPlace<'tcx>) -> String {
     let name = match place.base {
         HirPlaceBase::Upvar(upvar_id) => tcx.hir().name(upvar_id.var_path.hir_id).to_string(),