Conflict resolution and conversion to ConstraintFix class

Author: gregomni

lib/Sema/CSFix.cpp

@@ -104,6 +104,17 @@ AddAddressOf *AddAddressOf::create(ConstraintSystem &cs,
   return new (cs.getAllocator()) AddAddressOf(locator);
 }
 
+bool TreatRValueAsLValue::diagnose(Expr *root, const Solution &solution) const {
+  RValueTreatedAsLValueFailure failure(solution, getLocator());
+  return failure.diagnose();
+}
+
+TreatRValueAsLValue *TreatRValueAsLValue::create(ConstraintSystem &cs,
+                                   ConstraintLocator *locator) {
+  return new (cs.getAllocator()) TreatRValueAsLValue(locator);
+}
+
+
 bool CoerceToCheckedCast::diagnose(Expr *root, const Solution &solution) const {
   MissingForcedDowncastFailure failure(root, solution, getLocator());
   return failure.diagnose();

lib/Sema/CSFix.h

@@ -68,6 +68,9 @@ enum class FixKind : uint8_t {
 
   /// Add a new conformance to the type to satisfy a requirement.
   AddConformance,
+
+  /// Treat rvalue as lvalue
+  TreatRValueAsLValue,
 };
 
 class ConstraintFix {
@@ -168,6 +171,20 @@ class AddAddressOf final : public ConstraintFix {
   static AddAddressOf *create(ConstraintSystem &cs, ConstraintLocator *locator);
 };
 
+// Treat rvalue as if it was an lvalue
+class TreatRValueAsLValue final : public ConstraintFix {
+  TreatRValueAsLValue(ConstraintLocator *locator)
+    : ConstraintFix(FixKind::TreatRValueAsLValue, locator) {}
+
+public:
+  std::string getName() const override { return "treat rvalue as lvalue"; }
+
+  bool diagnose(Expr *root, const Solution &solution) const override;
+
+  static TreatRValueAsLValue *create(ConstraintSystem &cs, ConstraintLocator *locator);
+};
+
+
 /// Replace a coercion ('as') with a forced checked cast ('as!').
 class CoerceToCheckedCast final : public ConstraintFix {
   CoerceToCheckedCast(ConstraintLocator *locator)

lib/Sema/CSSimplify.cpp

@@ -2446,7 +2446,8 @@ ConstraintSystem::matchTypes(Type type1, Type type2, ConstraintKind kind,
           AddAddressOf::create(*this, getConstraintLocator(locator)));
       } else if (!isTypeVarOrMember1) {
         // If we have a concrete type that's an rvalue, "fix" it.
-        conversionsOrFixes.push_back(FixKind::TreatRValueAsLValue);
+        conversionsOrFixes.push_back(
+          TreatRValueAsLValue::create(*this, getConstraintLocator(locator)));
       }
     }
   }
@@ -4990,7 +4991,7 @@ ConstraintSystem::SolutionKind ConstraintSystem::simplifyFixConstraint(
     auto result = matchTypes(LValueType::get(type1), type2,
                              matchKind, subflags, locator);
     if (result == SolutionKind::Solved)
-      if (recordFix(fix, locator))
+      if (recordFix(fix))
         return SolutionKind::Error;
 
     return result;