Make LateCtxt be a type info delegate for EUV for clippy

10 files changed, 59 insertions, 61 deletions

diff --git a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
index 627c7b4a6c4..d5770dce675 100644
--- a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
+++ b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
@@ -9,6 +9,7 @@ use std::slice::from_ref;
 use hir::def::DefKind;
 use hir::pat_util::EnumerateAndAdjustIterator as _;
 use hir::Expr;
+use rustc_lint::LateContext;
 // Export these here so that Clippy can use them.
 pub use rustc_middle::hir::place::{Place, PlaceBase, PlaceWithHirId, Projection};
 
@@ -172,6 +173,36 @@ impl<'tcx> TypeInformationCtxt<'tcx> for &FnCtxt<'_, 'tcx> {
     }
 }
 
+impl<'tcx> TypeInformationCtxt<'tcx> for (&LateContext<'tcx>, LocalDefId) {
+    type TypeckResults<'a> = &'tcx ty::TypeckResults<'tcx>
+    where
+        Self: 'a;
+
+    fn typeck_results(&self) -> Self::TypeckResults<'_> {
+        self.0.maybe_typeck_results().expect("expected typeck results")
+    }
+
+    fn resolve_vars_if_possible<T: TypeFoldable<TyCtxt<'tcx>>>(&self, t: T) -> T {
+        t
+    }
+
+    fn tainted_by_errors(&self) -> Option<ErrorGuaranteed> {
+        None
+    }
+
+    fn type_is_copy_modulo_regions(&self, ty: Ty<'tcx>) -> bool {
+        ty.is_copy_modulo_regions(self.0.tcx, self.0.param_env)
+    }
+
+    fn body_owner_def_id(&self) -> LocalDefId {
+        self.1
+    }
+
+    fn tcx(&self) -> TyCtxt<'tcx> {
+        self.0.tcx
+    }
+}
+
 /// The ExprUseVisitor type
 ///
 /// This is the code that actually walks the tree.
@@ -200,13 +231,19 @@ macro_rules! return_if_err {
     };
 }
 
+impl<'a, 'tcx, D: Delegate<'tcx>> ExprUseVisitor<'tcx, (&'a LateContext<'tcx>, LocalDefId), D> {
+    pub fn for_clippy(cx: &'a LateContext<'tcx>, body_def_id: LocalDefId, delegate: D) -> Self {
+        Self::new((cx, body_def_id), delegate)
+    }
+}
+
 impl<'tcx, Cx: TypeInformationCtxt<'tcx>, D: Delegate<'tcx>> ExprUseVisitor<'tcx, Cx, D> {
     /// Creates the ExprUseVisitor, configuring it with the various options provided:
     ///
     /// - `delegate` -- who receives the callbacks
     /// - `param_env` --- parameter environment for trait lookups (esp. pertaining to `Copy`)
     /// - `typeck_results` --- typeck results for the code being analyzed
-    pub fn new(cx: Cx, delegate: D) -> Self {
+    pub(crate) fn new(cx: Cx, delegate: D) -> Self {
         ExprUseVisitor {
             delegate: RefCell::new(delegate),
             upvars: cx.tcx().upvars_mentioned(cx.body_owner_def_id()),
diff --git a/src/tools/clippy/clippy_lints/src/escape.rs b/src/tools/clippy/clippy_lints/src/escape.rs
index 386d4c3c317..6392ca13df1 100644
--- a/src/tools/clippy/clippy_lints/src/escape.rs
+++ b/src/tools/clippy/clippy_lints/src/escape.rs
@@ -1,7 +1,6 @@
 use clippy_utils::diagnostics::span_lint_hir;
 use rustc_hir::{intravisit, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node, Pat, PatKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::layout::LayoutOf;
@@ -105,8 +104,7 @@ impl<'tcx> LateLintPass<'tcx> for BoxedLocal {
             too_large_for_stack: self.too_large_for_stack,
         };
 
-        let infcx = cx.tcx.infer_ctxt().build();
-        ExprUseVisitor::new(&mut v, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+        ExprUseVisitor::for_clippy(cx, fn_def_id, &mut v).consume_body(body);
 
         for node in v.set {
             span_lint_hir(
diff --git a/src/tools/clippy/clippy_lints/src/loops/mut_range_bound.rs b/src/tools/clippy/clippy_lints/src/loops/mut_range_bound.rs
index 5047092192f..082c5977cbd 100644
--- a/src/tools/clippy/clippy_lints/src/loops/mut_range_bound.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/mut_range_bound.rs
@@ -4,7 +4,6 @@ use clippy_utils::{get_enclosing_block, higher, path_to_local};
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{BindingMode, Expr, ExprKind, HirId, Node, PatKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty;
@@ -61,13 +60,10 @@ fn check_for_mutation(
         span_low: None,
         span_high: None,
     };
-    let infcx = cx.tcx.infer_ctxt().build();
-    ExprUseVisitor::new(
-        &mut delegate,
-        &infcx,
+    ExprUseVisitor::for_clippy(
+        cx,
         body.hir_id.owner.def_id,
-        cx.param_env,
-        cx.typeck_results(),
+        &mut delegate,
     )
     .walk_expr(body);
 
diff --git a/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs b/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
index deac159457a..d4c709de97f 100644
--- a/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
@@ -69,14 +69,11 @@ pub(super) fn check<'tcx>(
             let mut delegate = MoveDelegate {
                 used_move: HirIdSet::default(),
             };
-            let infcx = cx.tcx.infer_ctxt().build();
 
-            ExprUseVisitor::new(
+            ExprUseVisitor::for_clippy(
+                cx,
+                closure.def_id,
                 &mut delegate,
-                &infcx,
-                closure.body.hir_id.owner.def_id,
-                cx.param_env,
-                cx.typeck_results(),
             )
             .consume_body(body);
 
diff --git a/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs b/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs
index 9e47c3ad0b7..5e786c1277a 100644
--- a/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs
@@ -11,7 +11,6 @@ use rustc_hir::{
     PatKind,
 };
 use rustc_hir_typeck::expr_use_visitor as euv;
-use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, Ty, TyCtxt, UpvarId, UpvarPath};
@@ -102,7 +101,6 @@ fn should_skip<'tcx>(
 fn check_closures<'tcx>(
     ctx: &mut MutablyUsedVariablesCtxt<'tcx>,
     cx: &LateContext<'tcx>,
-    infcx: &InferCtxt<'tcx>,
     checked_closures: &mut FxHashSet<LocalDefId>,
     closures: FxHashSet<LocalDefId>,
 ) {
@@ -119,7 +117,7 @@ fn check_closures<'tcx>(
             .associated_body()
             .map(|(_, body_id)| hir.body(body_id))
         {
-            euv::ExprUseVisitor::new(ctx, infcx, closure, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, closure, &mut *ctx).consume_body(body);
         }
     }
 }
@@ -196,8 +194,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByRefMut<'tcx> {
                 async_closures: FxHashSet::default(),
                 tcx: cx.tcx,
             };
-            let infcx = cx.tcx.infer_ctxt().build();
-            euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, fn_def_id, &mut ctx).consume_body(body);
 
             let mut checked_closures = FxHashSet::default();
 
@@ -210,13 +207,13 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByRefMut<'tcx> {
                 }
                 ControlFlow::<()>::Continue(())
             });
-            check_closures(&mut ctx, cx, &infcx, &mut checked_closures, closures);
+            check_closures(&mut ctx, cx, &mut checked_closures, closures);
 
             if is_async {
                 while !ctx.async_closures.is_empty() {
                     let async_closures = ctx.async_closures.clone();
                     ctx.async_closures.clear();
-                    check_closures(&mut ctx, cx, &infcx, &mut checked_closures, async_closures);
+                    check_closures(&mut ctx, cx, &mut checked_closures, async_closures);
                 }
             }
             ctx.generate_mutably_used_ids_from_aliases()
diff --git a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
index 39d374d0d27..60523ae0d0e 100644
--- a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
@@ -13,7 +13,6 @@ use rustc_hir::{
     TyKind,
 };
 use rustc_hir_typeck::expr_use_visitor as euv;
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, Ty, TypeVisitableExt};
@@ -134,8 +133,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
         // function body.
         let MovedVariablesCtxt { moved_vars } = {
             let mut ctx = MovedVariablesCtxt::default();
-            let infcx = cx.tcx.infer_ctxt().build();
-            euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, fn_def_id, &mut ctx).consume_body(body);
             ctx
         };
 
diff --git a/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs b/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
index 8effe6ab54d..6d617447bb5 100644
--- a/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
@@ -11,7 +11,6 @@ use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, Pl
 use rustc_lint::LateContext;
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::BorrowKind;
-use rustc_trait_selection::infer::TyCtxtInferExt;
 
 use super::ASSIGN_OP_PATTERN;
 
@@ -119,14 +118,7 @@ fn imm_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
     }
 
     let mut s = S(HirIdSet::default());
-    let infcx = cx.tcx.infer_ctxt().build();
-    let v = ExprUseVisitor::new(
-        &mut s,
-        &infcx,
-        cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),
-        cx.param_env,
-        cx.typeck_results(),
-    );
+    let v = ExprUseVisitor::for_clippy(cx, e.hir_id.owner.def_id, &mut s);
     v.consume_expr(e);
     s.0
 }
@@ -151,14 +143,7 @@ fn mut_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
     }
 
     let mut s = S(HirIdSet::default());
-    let infcx = cx.tcx.infer_ctxt().build();
-    let v = ExprUseVisitor::new(
-        &mut s,
-        &infcx,
-        cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),
-        cx.param_env,
-        cx.typeck_results(),
-    );
+    let v = ExprUseVisitor::for_clippy(cx, e.hir_id.owner.def_id, &mut s);
     v.consume_expr(e);
     s.0
 }
diff --git a/src/tools/clippy/clippy_lints/src/unwrap.rs b/src/tools/clippy/clippy_lints/src/unwrap.rs
index 6aec3dfa45c..aa5555d65f6 100644
--- a/src/tools/clippy/clippy_lints/src/unwrap.rs
+++ b/src/tools/clippy/clippy_lints/src/unwrap.rs
@@ -6,7 +6,6 @@ use rustc_errors::Applicability;
 use rustc_hir::intravisit::{walk_expr, walk_fn, FnKind, Visitor};
 use rustc_hir::{BinOpKind, Body, Expr, ExprKind, FnDecl, HirId, Node, PathSegment, UnOp};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::lint::in_external_macro;
@@ -252,13 +251,10 @@ impl<'a, 'tcx> UnwrappableVariablesVisitor<'a, 'tcx> {
                 local_id: unwrap_info.local_id,
             };
 
-            let infcx = self.cx.tcx.infer_ctxt().build();
-            let vis = ExprUseVisitor::new(
-                &mut delegate,
-                &infcx,
+            let vis = ExprUseVisitor::for_clippy(
+                self.cx,
                 cond.hir_id.owner.def_id,
-                self.cx.param_env,
-                self.cx.typeck_results(),
+                &mut delegate,
             );
             vis.walk_expr(cond);
             vis.walk_expr(branch);
diff --git a/src/tools/clippy/clippy_utils/src/sugg.rs b/src/tools/clippy/clippy_utils/src/sugg.rs
index 8d6057272c4..49b0eb05d2a 100644
--- a/src/tools/clippy/clippy_utils/src/sugg.rs
+++ b/src/tools/clippy/clippy_utils/src/sugg.rs
@@ -11,7 +11,6 @@ use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_hir::{Closure, ExprKind, HirId, MutTy, TyKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{EarlyContext, LateContext, LintContext};
 use rustc_middle::hir::place::ProjectionKind;
 use rustc_middle::mir::{FakeReadCause, Mutability};
@@ -831,8 +830,7 @@ pub fn deref_closure_args(cx: &LateContext<'_>, closure: &hir::Expr<'_>) -> Opti
             applicability: Applicability::MachineApplicable,
         };
 
-        let infcx = cx.tcx.infer_ctxt().build();
-        ExprUseVisitor::new(&mut visitor, &infcx, def_id, cx.param_env, cx.typeck_results()).consume_body(closure_body);
+        ExprUseVisitor::for_clippy(cx, def_id, &mut visitor).consume_body(closure_body);
 
         if !visitor.suggestion_start.is_empty() {
             return Some(DerefClosure {
diff --git a/src/tools/clippy/clippy_utils/src/usage.rs b/src/tools/clippy/clippy_utils/src/usage.rs
index a145920aa85..d0ab6d434aa 100644
--- a/src/tools/clippy/clippy_utils/src/usage.rs
+++ b/src/tools/clippy/clippy_utils/src/usage.rs
@@ -5,7 +5,6 @@ use hir::def::Res;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{self as hir, Expr, ExprKind, HirId, HirIdSet};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, Place, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::mir::FakeReadCause;
@@ -17,13 +16,10 @@ pub fn mutated_variables<'tcx>(expr: &'tcx Expr<'_>, cx: &LateContext<'tcx>) ->
         used_mutably: HirIdSet::default(),
         skip: false,
     };
-    let infcx = cx.tcx.infer_ctxt().build();
-    ExprUseVisitor::new(
-        &mut delegate,
-        &infcx,
+    ExprUseVisitor::for_clippy(
+        cx,
         expr.hir_id.owner.def_id,
-        cx.param_env,
-        cx.typeck_results(),
+        &mut delegate,
     )
     .walk_expr(expr);