Make assumption functions in new solver take clause

compiler/rustc_middle/src/ty/mod.rs

@@ -586,6 +586,24 @@ pub enum Clause<'tcx> {
     ConstArgHasType(Const<'tcx>, Ty<'tcx>),
 }
 
+impl<'tcx> Binder<'tcx, Clause<'tcx>> {
+    pub fn as_trait_clause(self) -> Option<Binder<'tcx, TraitPredicate<'tcx>>> {
+        if let ty::Clause::Trait(trait_clause) = self.skip_binder() {
+            Some(self.rebind(trait_clause))
+        } else {
+            None
+        }
+    }
+
+    pub fn as_projection_clause(self) -> Option<Binder<'tcx, ProjectionPredicate<'tcx>>> {
+        if let ty::Clause::Projection(projection_clause) = self.skip_binder() {
+            Some(self.rebind(projection_clause))
+        } else {
+            None
+        }
+    }
+}
+
 #[derive(Clone, Copy, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
 #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
 pub enum PredicateKind<'tcx> {
@@ -1203,6 +1221,17 @@ impl<'tcx> ToPredicate<'tcx> for TraitRef<'tcx> {
     }
 }
 
+impl<'tcx> ToPredicate<'tcx, Binder<'tcx, Clause<'tcx>>> for TraitRef<'tcx> {
+    #[inline(always)]
+    fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> Binder<'tcx, Clause<'tcx>> {
+        Binder::dummy(Clause::Trait(TraitPredicate {
+            trait_ref: self,
+            constness: ty::BoundConstness::NotConst,
+            polarity: ty::ImplPolarity::Positive,
+        }))
+    }
+}
+
 impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, TraitRef<'tcx>> {
     #[inline(always)]
     fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> {
@@ -1211,6 +1240,14 @@ impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, TraitRef<'tcx>> {
     }
 }
 
+impl<'tcx> ToPredicate<'tcx, Binder<'tcx, Clause<'tcx>>> for Binder<'tcx, TraitRef<'tcx>> {
+    #[inline(always)]
+    fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Binder<'tcx, Clause<'tcx>> {
+        let pred: PolyTraitPredicate<'tcx> = self.to_predicate(tcx);
+        pred.to_predicate(tcx)
+    }
+}
+
 impl<'tcx> ToPredicate<'tcx, PolyTraitPredicate<'tcx>> for Binder<'tcx, TraitRef<'tcx>> {
     #[inline(always)]
     fn to_predicate(self, _: TyCtxt<'tcx>) -> PolyTraitPredicate<'tcx> {
@@ -1240,6 +1277,12 @@ impl<'tcx> ToPredicate<'tcx> for PolyTraitPredicate<'tcx> {
     }
 }
 
+impl<'tcx> ToPredicate<'tcx, Binder<'tcx, Clause<'tcx>>> for PolyTraitPredicate<'tcx> {
+    fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> Binder<'tcx, Clause<'tcx>> {
+        self.map_bound(|p| Clause::Trait(p))
+    }
+}
+
 impl<'tcx> ToPredicate<'tcx> for PolyRegionOutlivesPredicate<'tcx> {
     fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> {
         self.map_bound(|p| PredicateKind::Clause(Clause::RegionOutlives(p))).to_predicate(tcx)
@@ -1258,6 +1301,12 @@ impl<'tcx> ToPredicate<'tcx> for PolyProjectionPredicate<'tcx> {
     }
 }
 
+impl<'tcx> ToPredicate<'tcx, Binder<'tcx, Clause<'tcx>>> for PolyProjectionPredicate<'tcx> {
+    fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> Binder<'tcx, Clause<'tcx>> {
+        self.map_bound(|p| Clause::Projection(p))
+    }
+}
+
 impl<'tcx> ToPredicate<'tcx> for TraitPredicate<'tcx> {
     fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> {
         PredicateKind::Clause(Clause::Trait(self)).to_predicate(tcx)
@@ -1327,6 +1376,23 @@ impl<'tcx> Predicate<'tcx> {
             | PredicateKind::TypeWellFormedFromEnv(..) => None,
         }
     }
+
+    pub fn as_clause(self) -> Option<Binder<'tcx, Clause<'tcx>>> {
+        let predicate = self.kind();
+        match predicate.skip_binder() {
+            PredicateKind::Clause(clause) => Some(predicate.rebind(clause)),
+            PredicateKind::AliasRelate(..)
+            | PredicateKind::Subtype(..)
+            | PredicateKind::Coerce(..)
+            | PredicateKind::WellFormed(..)
+            | PredicateKind::ObjectSafe(..)
+            | PredicateKind::ClosureKind(..)
+            | PredicateKind::ConstEvaluatable(..)
+            | PredicateKind::ConstEquate(..)
+            | PredicateKind::Ambiguous
+            | PredicateKind::TypeWellFormedFromEnv(..) => None,
+        }
+    }
 }
 
 /// Represents the bounds declared on a particular set of type