Only add explicit opaque types to module interfaces

Author: angela-laar

include/swift/AST/SourceFile.h

@@ -143,6 +143,10 @@ class SourceFile final : public FileUnit {
   /// The scope map that describes this source file.
   NullablePtr<ASTScope> Scope = nullptr;
 
+   /// The set of parsed decls with opaque return types that have not yet
+   /// been validated.
+   llvm::SetVector<ValueDecl *> UnvalidatedDeclsWithOpaqueReturnTypes;
+  
   /// The set of validated opaque return type decls in the source file.
   llvm::SmallVector<OpaqueTypeDecl *, 4> OpaqueReturnTypes;
   llvm::StringMap<OpaqueTypeDecl *> ValidatedOpaqueReturnTypes;
@@ -664,6 +668,13 @@ class SourceFile final : public FileUnit {
 
   OpaqueTypeDecl *lookupOpaqueResultType(StringRef MangledName) override;
 
+  /// Do not call when inside an inactive clause (\c
+  /// InInactiveClauseEnvironment)) because it will later on result in a lookup
+  /// to something that won't be in the ASTScope tree.
+  void addUnvalidatedDeclWithOpaqueResultType(ValueDecl *vd) {
+    UnvalidatedDeclsWithOpaqueReturnTypes.insert(vd);
+  }
+
   void addOpaqueResultTypeDecl(OpaqueTypeDecl *decl) {
     UnvalidatedOpaqueReturnTypes.insert(decl);
   }

lib/AST/Module.cpp

@@ -3613,12 +3613,14 @@ void SourceFile::setTypeRefinementContext(TypeRefinementContext *Root) {
 }
 
 ArrayRef<OpaqueTypeDecl *> SourceFile::getOpaqueReturnTypeDecls() {
-  for (auto *opaqueDecl : UnvalidatedOpaqueReturnTypes.takeVector()) {
-    auto inserted = ValidatedOpaqueReturnTypes.insert(
-              {opaqueDecl->getOpaqueReturnTypeIdentifier().str(),
-               opaqueDecl});
-    if (inserted.second) {
-      OpaqueReturnTypes.push_back(opaqueDecl);
+  for (auto *vd : UnvalidatedDeclsWithOpaqueReturnTypes.takeVector()) {
+    if (auto opaqueDecl = vd->getOpaqueResultTypeDecl()) {
+      auto inserted = ValidatedOpaqueReturnTypes.insert(
+                {opaqueDecl->getOpaqueReturnTypeIdentifier().str(),
+                 opaqueDecl});
+      if (inserted.second) {
+        OpaqueReturnTypes.push_back(opaqueDecl);
+      }
     }
   }
 

lib/Parse/ParseDecl.cpp

@@ -7506,6 +7506,12 @@ Parser::parseDeclVar(ParseDeclOptions Flags,
       pattern = patternRes.get();
     }
 
+    bool hasOpaqueReturnTy = false;
+    if (auto typedPattern = dyn_cast<TypedPattern>(pattern)) {
+      hasOpaqueReturnTy = typedPattern->getTypeRepr()->hasOpaque();
+    }
+    auto sf = CurDeclContext->getParentSourceFile();
+    
     // Configure all vars with attributes, 'static' and parent pattern.
     pattern->forEachVariable([&](VarDecl *VD) {
       VD->setStatic(StaticLoc.isValid());
@@ -7516,6 +7522,9 @@ Parser::parseDeclVar(ParseDeclOptions Flags,
       setOriginalDeclarationForDifferentiableAttributes(Attributes, VD);
 
       Decls.push_back(VD);
+      if (hasOpaqueReturnTy && sf && !InInactiveClauseEnvironment) {
+        sf->addUnvalidatedDeclWithOpaqueResultType(VD);
+      }
     });
 
     // Check whether we have already established an initializer context.
@@ -7800,6 +7809,14 @@ ParserResult<FuncDecl> Parser::parseDeclFunc(SourceLoc StaticLoc,
                               GenericParams,
                               BodyParams, FuncRetTy,
                               CurDeclContext);
+
+  // Let the source file track the opaque return type mapping, if any.
+  if (FuncRetTy && FuncRetTy->hasOpaque() &&
+      !InInactiveClauseEnvironment) {
+    if (auto sf = CurDeclContext->getParentSourceFile()) {
+      sf->addUnvalidatedDeclWithOpaqueResultType(FD);
+    }
+  }
 
   // Parse a 'where' clause if present.
   if (Tok.is(tok::kw_where)) {
@@ -8730,6 +8747,14 @@ Parser::parseDeclSubscript(SourceLoc StaticLoc,
       Context, name, StaticLoc, StaticSpelling, SubscriptLoc, Indices.get(),
       ArrowLoc, ElementTy.get(), CurDeclContext, GenericParams);
   Subscript->getAttrs() = Attributes;
+  
+  // Let the source file track the opaque return type mapping, if any.
+  if (ElementTy.get() && ElementTy.get()->hasOpaque() &&
+      !InInactiveClauseEnvironment) {
+    if (auto sf = CurDeclContext->getParentSourceFile()) {
+      sf->addUnvalidatedDeclWithOpaqueResultType(Subscript);
+    }
+  }
 
   DefaultArgs.setFunctionContext(Subscript, Subscript->getIndices());
 

test/IRGen/Inputs/implicit_some_b.swift

@@ -0,0 +1,3 @@
+func bar() {
+  let x = foo()
+}

test/IRGen/implicit_some_a.swift

@@ -0,0 +1,6 @@
+// RUN: %target-swift-frontend -primary-file %s %S/Inputs/implicit_some_b.swift -enable-experimental-feature ImplicitSome -emit-ir
+
+protocol P {}
+struct S: P {}
+
+func foo() -> P { return S() }

test/type/implicit_some/opaque_parameters.swift

@@ -64,7 +64,7 @@ func consumingB(fn: FnType<P>) { } // expected-error{{'some' cannot appear in pa
 
 // TO-DO Handle plain generic opaque parameters
 func takePrimaryCollections(
-  _ strings:some  Collection<String>,
+  _ strings:some Collection<String>,
   _ ints : some Collection<Int>
 ) {
   for s in strings {