Rollup merge of #123103 - compiler-errors:inherited-is-a-weird-name, …

…r=oli-obk

Rename `Inherited` -> `TypeckRootCtxt`

`Inherited` is a confusing name. Rename it to `TypeckRootCtxt`.

I don't think this needs a type MCP or anything since it's not nearly as pervasive as `FnCtxt` , for example.

r? `@lcnr` `@oli-obk`

compiler/rustc_hir_typeck/src/_match.rs

@@ -243,7 +243,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let can_coerce_to_return_ty = match self.ret_coercion.as_ref() {
             Some(ret_coercion) => {
                 let ret_ty = ret_coercion.borrow().expected_ty();
-                let ret_ty = self.inh.infcx.shallow_resolve(ret_ty);
+                let ret_ty = self.infcx.shallow_resolve(ret_ty);
                 self.can_coerce(arm_ty, ret_ty)
                     && prior_arm.map_or(true, |(_, ty, _)| self.can_coerce(ty, ret_ty))
                     // The match arms need to unify for the case of `impl Trait`.

compiler/rustc_hir_typeck/src/closure.rs

@@ -848,7 +848,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             bound_vars,
         );
 
-        let c_result = self.inh.infcx.canonicalize_response(result);
+        let c_result = self.infcx.canonicalize_response(result);
         self.typeck_results.borrow_mut().user_provided_sigs.insert(expr_def_id, c_result);
 
         // Normalize only after registering in `user_provided_sigs`.

compiler/rustc_hir_typeck/src/fallback.rs

@@ -347,7 +347,6 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
                 .any(|n| roots_reachable_from_non_diverging.visited(n));
 
             let infer_var_infos: UnordBag<_> = self
-                .inh
                 .infer_var_info
                 .borrow()
                 .items()

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -526,7 +526,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub(in super::super) fn resolve_rvalue_scopes(&self, def_id: DefId) {
         let scope_tree = self.tcx.region_scope_tree(def_id);
         let rvalue_scopes = { rvalue_scopes::resolve_rvalue_scopes(self, scope_tree, def_id) };
-        let mut typeck_results = self.inh.typeck_results.borrow_mut();
+        let mut typeck_results = self.typeck_results.borrow_mut();
         typeck_results.rvalue_scopes = rvalue_scopes;
     }
 

compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs

@@ -7,7 +7,7 @@ mod suggestions;
 use crate::coercion::DynamicCoerceMany;
 use crate::fallback::DivergingFallbackBehavior;
 use crate::fn_ctxt::checks::DivergingBlockBehavior;
-use crate::{CoroutineTypes, Diverges, EnclosingBreakables, Inherited};
+use crate::{CoroutineTypes, Diverges, EnclosingBreakables, TypeckRootCtxt};
 use hir::def_id::CRATE_DEF_ID;
 use rustc_errors::{DiagCtxt, ErrorGuaranteed};
 use rustc_hir as hir;
@@ -108,7 +108,7 @@ pub struct FnCtxt<'a, 'tcx> {
 
     pub(super) enclosing_breakables: RefCell<EnclosingBreakables<'tcx>>,
 
-    pub(super) inh: &'a Inherited<'tcx>,
+    pub(super) root_ctxt: &'a TypeckRootCtxt<'tcx>,
 
     pub(super) fallback_has_occurred: Cell<bool>,
 
@@ -118,12 +118,12 @@ pub struct FnCtxt<'a, 'tcx> {
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn new(
-        inh: &'a Inherited<'tcx>,
+        root_ctxt: &'a TypeckRootCtxt<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
         body_id: LocalDefId,
     ) -> FnCtxt<'a, 'tcx> {
         let (diverging_fallback_behavior, diverging_block_behavior) =
-            parse_never_type_options_attr(inh.tcx);
+            parse_never_type_options_attr(root_ctxt.tcx);
         FnCtxt {
             body_id,
             param_env,
@@ -137,7 +137,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 stack: Vec::new(),
                 by_id: Default::default(),
             }),
-            inh,
+            root_ctxt,
             fallback_has_occurred: Cell::new(false),
             diverging_fallback_behavior,
             diverging_block_behavior,
@@ -206,9 +206,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> Deref for FnCtxt<'a, 'tcx> {
-    type Target = Inherited<'tcx>;
+    type Target = TypeckRootCtxt<'tcx>;
     fn deref(&self) -> &Self::Target {
-        self.inh
+        self.root_ctxt
     }
 }
 

compiler/rustc_hir_typeck/src/gather_locals.rs

@@ -95,8 +95,7 @@ impl<'a, 'tcx> GatherLocalsVisitor<'a, 'tcx> {
             Some(ref ty) => {
                 let o_ty = self.fcx.lower_ty(ty);
 
-                let c_ty =
-                    self.fcx.inh.infcx.canonicalize_user_type_annotation(UserType::Ty(o_ty.raw));
+                let c_ty = self.fcx.infcx.canonicalize_user_type_annotation(UserType::Ty(o_ty.raw));
                 debug!("visit_local: ty.hir_id={:?} o_ty={:?} c_ty={:?}", ty.hir_id, o_ty, c_ty);
                 self.fcx
                     .typeck_results

compiler/rustc_hir_typeck/src/lib.rs

@@ -31,19 +31,19 @@ pub mod expr_use_visitor;
 mod fallback;
 mod fn_ctxt;
 mod gather_locals;
-mod inherited;
 mod intrinsicck;
 mod mem_categorization;
 mod method;
 mod op;
 mod pat;
 mod place_op;
 mod rvalue_scopes;
+mod typeck_root_ctxt;
 mod upvar;
 mod writeback;
 
 pub use fn_ctxt::FnCtxt;
-pub use inherited::Inherited;
+pub use typeck_root_ctxt::TypeckRootCtxt;
 
 use crate::check::check_fn;
 use crate::coercion::DynamicCoerceMany;
@@ -170,11 +170,11 @@ fn typeck_with_fallback<'tcx>(
 
     let param_env = tcx.param_env(def_id);
 
-    let inh = Inherited::new(tcx, def_id);
+    let root_ctxt = TypeckRootCtxt::new(tcx, def_id);
     if let Some(inspector) = inspector {
-        inh.infcx.attach_obligation_inspector(inspector);
+        root_ctxt.infcx.attach_obligation_inspector(inspector);
     }
-    let mut fcx = FnCtxt::new(&inh, param_env, def_id);
+    let mut fcx = FnCtxt::new(&root_ctxt, param_env, def_id);
 
     if let Some(hir::FnSig { header, decl, .. }) = fn_sig {
         let fn_sig = if decl.output.get_infer_ret_ty().is_some() {

compiler/rustc_hir_typeck/src/pat.rs

@@ -388,8 +388,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         if !pat_adjustments.is_empty() {
             debug!("default binding mode is now {:?}", def_bm);
-            self.inh
-                .typeck_results
+            self.typeck_results
                 .borrow_mut()
                 .pat_adjustments_mut()
                 .insert(pat.hir_id, pat_adjustments);
@@ -614,7 +613,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             _ => BindingMode::convert(ba),
         };
         // ...and store it in a side table:
-        self.inh.typeck_results.borrow_mut().pat_binding_modes_mut().insert(pat.hir_id, bm);
+        self.typeck_results.borrow_mut().pat_binding_modes_mut().insert(pat.hir_id, bm);
 
         debug!("check_pat_ident: pat.hir_id={:?} bm={:?}", pat.hir_id, bm);
 

compiler/rustc_hir_typeck/src/inherited.rs → compiler/rustc_hir_typeck/src/typeck_root_ctxt.rs

@@ -16,16 +16,18 @@ use rustc_trait_selection::traits::{self, PredicateObligation, TraitEngine, Trai
 use std::cell::RefCell;
 use std::ops::Deref;
 
-/// Closures defined within the function. For example:
+// Data shared between a "typeck root" and its nested bodies,
+/// e.g. closures defined within the function. For example:
 /// ```ignore (illustrative)
 /// fn foo() {
 ///     bar(move|| { ... })
 /// }
 /// ```
 /// Here, the function `foo()` and the closure passed to
 /// `bar()` will each have their own `FnCtxt`, but they will
-/// share the inherited fields.
-pub struct Inherited<'tcx> {
+/// share the inference context, will process obligations together,
+/// can access each other's local types (scoping permitted), etc.
+pub struct TypeckRootCtxt<'tcx> {
     pub(super) infcx: InferCtxt<'tcx>,
 
     pub(super) typeck_results: RefCell<ty::TypeckResults<'tcx>>,
@@ -65,14 +67,14 @@ pub struct Inherited<'tcx> {
     pub(super) infer_var_info: RefCell<UnordMap<ty::TyVid, ty::InferVarInfo>>,
 }
 
-impl<'tcx> Deref for Inherited<'tcx> {
+impl<'tcx> Deref for TypeckRootCtxt<'tcx> {
     type Target = InferCtxt<'tcx>;
     fn deref(&self) -> &Self::Target {
         &self.infcx
     }
 }
 
-impl<'tcx> Inherited<'tcx> {
+impl<'tcx> TypeckRootCtxt<'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> Self {
         let hir_owner = tcx.local_def_id_to_hir_id(def_id).owner;
 
@@ -83,7 +85,7 @@ impl<'tcx> Inherited<'tcx> {
             .build();
         let typeck_results = RefCell::new(ty::TypeckResults::new(hir_owner));
 
-        Inherited {
+        TypeckRootCtxt {
             typeck_results,
             fulfillment_cx: RefCell::new(<dyn TraitEngine<'_>>::new(&infcx)),
             infcx,

src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs

@@ -12,7 +12,7 @@ use rustc_errors::Applicability;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::{BorrowKind, Expr, ExprKind, ItemKind, LangItem, Node};
-use rustc_hir_typeck::{FnCtxt, Inherited};
+use rustc_hir_typeck::{FnCtxt, TypeckRootCtxt};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
 use rustc_middle::mir::Mutability;
@@ -438,8 +438,8 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
             Node::Item(item) => {
                 if let ItemKind::Fn(_, _, body_id) = &item.kind
                     && let output_ty = return_ty(cx, item.owner_id)
-                    && let inherited = Inherited::new(cx.tcx, item.owner_id.def_id)
-                    && let fn_ctxt = FnCtxt::new(&inherited, cx.param_env, item.owner_id.def_id)
+                    && let root_ctxt = TypeckRootCtxt::new(cx.tcx, item.owner_id.def_id)
+                    && let fn_ctxt = FnCtxt::new(&root_ctxt, cx.param_env, item.owner_id.def_id)
                     && fn_ctxt.can_coerce(ty, output_ty)
                 {
                     if has_lifetime(output_ty) && has_lifetime(ty) {

src/tools/clippy/clippy_lints/src/transmute/utils.rs

@@ -1,6 +1,6 @@
 use rustc_hir as hir;
 use rustc_hir::Expr;
-use rustc_hir_typeck::{cast, FnCtxt, Inherited};
+use rustc_hir_typeck::{cast, FnCtxt, TypeckRootCtxt};
 use rustc_lint::LateContext;
 use rustc_middle::ty::cast::CastKind;
 use rustc_middle::ty::Ty;
@@ -34,8 +34,8 @@ pub(super) fn check_cast<'tcx>(
     let hir_id = e.hir_id;
     let local_def_id = hir_id.owner.def_id;
 
-    let inherited = Inherited::new(cx.tcx, local_def_id);
-    let fn_ctxt = FnCtxt::new(&inherited, cx.param_env, local_def_id);
+    let root_ctxt = TypeckRootCtxt::new(cx.tcx, local_def_id);
+    let fn_ctxt = FnCtxt::new(&root_ctxt, cx.param_env, local_def_id);
 
     if let Ok(check) = cast::CastCheck::new(
         &fn_ctxt,