Auto merge of rust-lang#82536 - sexxi-goose:handle-patterns-take-2, r=nikomatsakis

2229: Handle patterns within closures correctly when `capture_disjoint_fields` is enabled

This PR fixes several issues related to handling patterns within closures when `capture_disjoint_fields` is enabled.
1. Matching is always considered a use of the place, even with `_` patterns
2. Compiler ICE when capturing fields in closures through `let` assignments

To do so, we

- Introduced new Fake Reads
- Delayed use of `Place` in favor of `PlaceBuilder`
- Ensured that `PlaceBuilder` can be resolved before attempting to extract `Place` in any of the pattern matching code

Closes rust-lang/project-rfc-2229/issues/27
Closes rust-lang/project-rfc-2229/issues/24
r? `@nikomatsakis`

Author: bors

clippy_lints/src/escape.rs

@@ -2,6 +2,7 @@ use rustc_hir::intravisit;
 use rustc_hir::{self, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, TraitRef, Ty};
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::source_map::Span;
@@ -184,6 +185,8 @@ impl<'a, 'tcx> Delegate<'tcx> for EscapeDelegate<'a, 'tcx> {
             }
         }
     }
+
+    fn fake_read(&mut self, _: rustc_typeck::expr_use_visitor::Place<'tcx>, _: FakeReadCause, _: HirId) { }
 }
 
 impl<'a, 'tcx> EscapeDelegate<'a, 'tcx> {

clippy_lints/src/loops/mut_range_bound.rs

@@ -4,6 +4,7 @@ use if_chain::if_chain;
 use rustc_hir::{BindingAnnotation, Expr, HirId, Node, PatKind};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
+use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty;
 use rustc_span::source_map::Span;
 use rustc_typeck::expr_use_visitor::{ConsumeMode, Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
@@ -106,6 +107,8 @@ impl<'tcx> Delegate<'tcx> for MutatePairDelegate<'_, 'tcx> {
             }
         }
     }
+
+    fn fake_read(&mut self, _: rustc_typeck::expr_use_visitor::Place<'tcx>, _: FakeReadCause, _:HirId) { }
 }
 
 impl MutatePairDelegate<'_, '_> {

clippy_lints/src/needless_pass_by_value.rs

@@ -11,6 +11,7 @@ use rustc_hir::intravisit::FnKind;
 use rustc_hir::{BindingAnnotation, Body, FnDecl, GenericArg, HirId, Impl, ItemKind, Node, PatKind, QPath, TyKind};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, TypeFoldable};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::symbol::kw;
@@ -333,4 +334,6 @@ impl<'tcx> euv::Delegate<'tcx> for MovedVariablesCtxt {
     fn borrow(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId, _: ty::BorrowKind) {}
 
     fn mutate(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId) {}
+
+    fn fake_read(&mut self, _: rustc_typeck::expr_use_visitor::Place<'tcx>, _: FakeReadCause, _: HirId) { }
 }

clippy_utils/src/usage.rs

@@ -7,6 +7,7 @@ use rustc_hir::intravisit::{NestedVisitorMap, Visitor};
 use rustc_hir::{Expr, ExprKind, HirId, Path};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
+use rustc_middle::mir::FakeReadCause;
 use rustc_middle::hir::map::Map;
 use rustc_middle::ty;
 use rustc_typeck::expr_use_visitor::{ConsumeMode, Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
@@ -77,6 +78,8 @@ impl<'tcx> Delegate<'tcx> for MutVarsDelegate {
     fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId) {
         self.update(&cmt)
     }
+
+    fn fake_read(&mut self, _: rustc_typeck::expr_use_visitor::Place<'tcx>, _: FakeReadCause, _:HirId) { }
 }
 
 pub struct ParamBindingIdCollector {