Rollup merge of rust-lang#152879 - nnethercote:rm-impl-IntoQueryParam-ref-P, r=oli-obk

Remove `impl IntoQueryParam<P> for &'a P`.

`IntoQueryParam` is a trait that lets query callers be a bit sloppy with the passed-in key.
- Types similar to `DefId` will be auto-converted to `DefId`. Likewise for `LocalDefId`.
- Reference types will be auto-derefed.

The auto-conversion is genuinely useful; the auto-derefing much less so. In practice it's only used for passing `&DefId` to queries that accept `DefId`, which is an anti-pattern because `DefId` is marked with `#[rustc_pass_by_value]`.

This commit removes the auto-deref impl and makes the necessary sigil adjustments. (I generally avoid using `*` to deref manually at call sites, preferring to deref via `&` in patterns or via `*` in match expressions. Mostly because that way a single deref often covers multiple call sites.)

r? @cjgillot

Author: JonathanBrouwer

compiler/rustc_borrowck/src/diagnostics/move_errors.rs

@@ -626,7 +626,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         let predicates = match parent.kind {
             hir::ExprKind::Call(callee, _) => {
                 let ty = typeck_result.node_type_opt(callee.hir_id)?;
-                let ty::FnDef(fn_def_id, args) = ty.kind() else { return None };
+                let ty::FnDef(fn_def_id, args) = *ty.kind() else { return None };
                 tcx.predicates_of(fn_def_id).instantiate(tcx, args)
             }
             hir::ExprKind::MethodCall(..) => {

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -614,7 +614,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                     }
                     _ => {
                         let local = &self.body.local_decls[local];
-                        match local.local_info() {
+                        match *local.local_info() {
                             LocalInfo::StaticRef { def_id, .. } => {
                                 let span = self.infcx.tcx.def_span(def_id);
                                 err.span_label(span, format!("this `static` cannot be {acted_on}"));

compiler/rustc_borrowck/src/diagnostics/region_errors.rs

@@ -926,7 +926,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         let tcx = self.infcx.tcx;
 
         let ConstraintCategory::CallArgument(Some(func_ty)) = category else { return };
-        let ty::FnDef(fn_did, args) = func_ty.kind() else { return };
+        let ty::FnDef(fn_did, args) = *func_ty.kind() else { return };
         debug!(?fn_did, ?args);
 
         // Only suggest this on function calls, not closures
@@ -938,7 +938,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         let Ok(Some(instance)) = ty::Instance::try_resolve(
             tcx,
             self.infcx.typing_env(self.infcx.param_env),
-            *fn_did,
+            fn_did,
             self.infcx.resolve_vars_if_possible(args),
         ) else {
             return;

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -1013,12 +1013,12 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                         let is_implicit_coercion = coercion_source == CoercionSource::Implicit;
                         let src_ty = op.ty(self.body, tcx);
                         let mut src_sig = src_ty.fn_sig(tcx);
-                        if let ty::FnDef(def_id, _) = src_ty.kind()
+                        if let ty::FnDef(def_id, _) = *src_ty.kind()
                             && let ty::FnPtr(_, target_hdr) = *ty.kind()
                             && tcx.codegen_fn_attrs(def_id).safe_target_features
                             && target_hdr.safety.is_safe()
                             && let Some(safe_sig) = tcx.adjust_target_feature_sig(
-                                *def_id,
+                                def_id,
                                 src_sig,
                                 self.body.source.def_id(),
                             )

compiler/rustc_const_eval/src/check_consts/check.rs

@@ -577,7 +577,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
 
             Rvalue::Aggregate(kind, ..) => {
                 if let AggregateKind::Coroutine(def_id, ..) = kind.as_ref()
-                    && let Some(coroutine_kind) = self.tcx.coroutine_kind(def_id)
+                    && let Some(coroutine_kind) = self.tcx.coroutine_kind(*def_id)
                 {
                     self.check_op(ops::Coroutine(coroutine_kind));
                 }

compiler/rustc_hir_analysis/src/check/check.rs

@@ -1221,7 +1221,7 @@ fn check_impl_items_against_trait<'tcx>(
     match impl_trait_header.polarity {
         ty::ImplPolarity::Reservation | ty::ImplPolarity::Positive => {}
         ty::ImplPolarity::Negative => {
-            if let [first_item_ref, ..] = impl_item_refs {
+            if let [first_item_ref, ..] = *impl_item_refs {
                 let first_item_span = tcx.def_span(first_item_ref);
                 struct_span_code_err!(
                     tcx.dcx(),

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -1333,7 +1333,7 @@ fn check_region_late_boundedness<'tcx>(
         .iter()
         .map(|param| {
             let (LateEarlyMismatch::EarlyInImpl(impl_param_def_id, ..)
-            | LateEarlyMismatch::LateInImpl(impl_param_def_id, ..)) = param;
+            | LateEarlyMismatch::LateInImpl(impl_param_def_id, ..)) = *param;
             tcx.def_span(impl_param_def_id)
         })
         .collect();

compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs

@@ -2445,12 +2445,12 @@ fn is_late_bound_map(
                 )) => {
                     // See comments on `ConstrainedCollectorPostHirTyLowering` for why this arm does not
                     // just consider args to be unconstrained.
-                    let generics = self.tcx.generics_of(alias_def);
+                    let generics = self.tcx.generics_of(*alias_def);
                     let mut walker = ConstrainedCollectorPostHirTyLowering {
                         arg_is_constrained: vec![false; generics.own_params.len()]
                             .into_boxed_slice(),
                     };
-                    walker.visit_ty(self.tcx.type_of(alias_def).instantiate_identity());
+                    walker.visit_ty(self.tcx.type_of(*alias_def).instantiate_identity());
 
                     match segments.last() {
                         Some(hir::PathSegment { args: Some(args), .. }) => {

compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs

@@ -214,7 +214,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             if let [best_trait] = visible_traits
                 .iter()
                 .copied()
-                .filter(|trait_def_id| {
+                .filter(|&trait_def_id| {
                     tcx.associated_items(trait_def_id)
                         .filter_by_name_unhygienic(suggested_name)
                         .any(|item| item.tag() == assoc_tag)
@@ -1234,7 +1234,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             && let name = Symbol::intern(&format!("{ident2}_{ident3}"))
             && let Some(item) = inherent_impls
                 .iter()
-                .flat_map(|inherent_impl| {
+                .flat_map(|&inherent_impl| {
                     tcx.associated_items(inherent_impl).filter_by_name_unhygienic(name)
                 })
                 .next()

compiler/rustc_hir_analysis/src/impl_wf_check.rs

@@ -101,7 +101,7 @@ pub(crate) fn enforce_impl_lifetime_params_are_constrained(
     let lifetimes_in_associated_types: FxHashSet<_> = tcx
         .associated_item_def_ids(impl_def_id)
         .iter()
-        .flat_map(|def_id| {
+        .flat_map(|&def_id| {
             let item = tcx.associated_item(def_id);
             match item.kind {
                 ty::AssocKind::Type { .. } => {