Serialization: Handle precedence groups and operators in ExternallyAccessibleDeclVisitor.

Author: tshortli

lib/Serialization/Serialization.cpp

@@ -3413,8 +3413,6 @@ class Serializer::DeclSerializer : public DeclVisitor<DeclSerializer> {
     UNREACHABLE(MacroExpansion);
     UNREACHABLE(GenericTypeParam);
     UNREACHABLE(Param);
-    UNREACHABLE(PrecedenceGroup);
-    UNREACHABLE(Operator);
 
 #undef UNREACHABLE
 
@@ -3427,7 +3425,9 @@ class Serializer::DeclSerializer : public DeclVisitor<DeclSerializer> {
 #define UNINTERESTING(KIND)                                                    \
   bool visit##KIND##Decl(const KIND##Decl *D) { return true; }
     UNINTERESTING(IfConfig);
+    UNINTERESTING(PrecedenceGroup);
     UNINTERESTING(EnumCase);
+    UNINTERESTING(Operator);
 
 #undef UNINTERESTING
   };

test/Inputs/lazy_typecheck.swift

@@ -256,3 +256,18 @@ extension PublicStruct {
   public static func inactiveMethod() -> DoesNotExist {}
 #endif
 }
+
+// MARK: - Operators & Precedence Groups
+
+precedencegroup FooPrecedence {
+  assignment: true
+  associativity: right
+}
+
+infix operator <<<: FooPrecedence
+
+extension PublicStruct {
+  public static func <<<(lhs: inout Self, rhs: Self) {
+    lhs = rhs
+  }
+}

test/Inputs/lazy_typecheck_client.swift

@@ -94,3 +94,8 @@ func testConditionalConformance<T>(_ s: PublicGenericStruct<T>) {
 func testTypealiases() {
   let _: PublicStruct = PublicStructAlias(x: 1)
 }
+
+func testOperators() {
+  var a: PublicStruct
+  a <<< PublicStruct(x: 2)
+}

test/ModuleInterface/lazy-typecheck.swift

@@ -106,6 +106,14 @@
 // CHECK:       extension lazy_typecheck.PublicStruct {
 // CHECK:         public static func activeMethod()
 // CHECK:       }
+// CHECK:       precedencegroup FooPrecedence {
+// CHECK:         associativity: right
+// CHECK:         assignment: true
+// CHECK:       }
+// CHECK:       infix operator <<< : FooPrecedence
+// CHECK:       extension lazy_typecheck.PublicStruct {
+// CHECK:         public static func <<< (lhs: inout lazy_typecheck.PublicStruct, rhs: lazy_typecheck.PublicStruct)
+// CHECK:       }
 // CHECK:       @available(*, unavailable)
 // CHECK-NEXT:  extension lazy_typecheck.PublicGenericStruct : lazy_typecheck.EmptyPublicProto where T : _ConstraintThatIsNotPartOfTheAPIOfThisLibrary {}
 // CHECK:       extension lazy_typecheck.PublicStructIndirectlyConformingToPublicProto : lazy_typecheck.PublicProto {}

test/TBD/lazy-typecheck.swift

@@ -102,8 +102,9 @@ exports:
                        '_$s14lazy_typecheck12PublicStructV26publicPropertyInferredTypeSSvg',
                        '_$s14lazy_typecheck12PublicStructV26publicPropertyInferredTypeSSvpMV',
                        '_$s14lazy_typecheck12PublicStructV26publicPropertyInferredTypeSSvs',
-                       '_$s14lazy_typecheck12PublicStructVMa', '_$s14lazy_typecheck12PublicStructVMn',
-                       '_$s14lazy_typecheck12PublicStructVN', '_$s14lazy_typecheck13PublicWrapperV12wrappedValueACyxGx_tcfC',
+                       '_$s14lazy_typecheck12PublicStructV3llloiyyACz_ACtFZ', '_$s14lazy_typecheck12PublicStructVMa',
+                       '_$s14lazy_typecheck12PublicStructVMn', '_$s14lazy_typecheck12PublicStructVN',
+                       '_$s14lazy_typecheck13PublicWrapperV12wrappedValueACyxGx_tcfC',
                        '_$s14lazy_typecheck13PublicWrapperV12wrappedValuexvM', '_$s14lazy_typecheck13PublicWrapperV12wrappedValuexvg',
                        '_$s14lazy_typecheck13PublicWrapperV12wrappedValuexvpMV',
                        '_$s14lazy_typecheck13PublicWrapperV12wrappedValuexvs', '_$s14lazy_typecheck13PublicWrapperV14projectedValueACyxGvg',