Fix protocol checking so it happens in the right order. Fixes <rdar://problem/11515674> in -parse-as-library mode.

A refactor of the various visitors in DeclChecker in TypeCheckDecl.cpp is coming up next.



Swift SVN r2000

Author: Eli Friedman

lib/Sema/TypeCheckDecl.cpp

@@ -49,27 +49,19 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
   /// \param CheckConformance Will be set true if the caller needs to call
   /// checkExplicitConformance() for this declaration once its members have
   /// been type-checked. Otherwise, the conformance check can be delayed.
-  void checkInherited(Decl *D, Type T, MutableArrayRef<Type> Inherited,
-                      bool &CheckConformance) {
+  void checkInherited(Decl *D, Type T, MutableArrayRef<Type> Inherited) {
     // Check the list of inherited protocols.
-    bool ConformsToProtocols = false;
     for (unsigned i = 0, e = Inherited.size(); i != e; ++i) {
       if (TC.validateType(Inherited[i], IsFirstPass)) {
         Inherited[i] = ErrorType::get(TC.Context);
         continue;
       }
 
-      if (!Inherited[i]->is<ProtocolType>()) {
+      if (!Inherited[i]->is<ProtocolType>() && !Inherited[i]->is<ErrorType>()) {
         // FIXME: Terrible location information.
         TC.diagnose(D->getLocStart(), diag::nonprotocol_inherit, Inherited[i]);
-      } else if (!Inherited[i]->is<ErrorType>()) {
-        ConformsToProtocols = true;
       }
     }
-    
-    CheckConformance = ConformsToProtocols &&
-      !D->getDeclContext()->isModuleContext() &&
-      !isa<ProtocolDecl>(D);
   }
 
   void checkExplicitConformance(Decl *D, Type T,
@@ -187,28 +179,36 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
   }
 
   void visitOneOfDecl(OneOfDecl *OOD) {
-    if (IsSecondPass)
+    if (IsSecondPass) {
+      for (auto elt : OOD->getElements())
+        visitOneOfElementDecl(elt);
+
+      checkExplicitConformance(OOD, OOD->getDeclaredType(),
+                               OOD->getInherited());
       return;
+    }
 
-    bool CheckConformance;
-    checkInherited(OOD, OOD->getDeclaredType(), OOD->getInherited(),
-                   CheckConformance);
+    checkInherited(OOD, OOD->getDeclaredType(), OOD->getInherited());
 
     for (auto elt : OOD->getElements())
       visitOneOfElementDecl(elt);
 
-    if (CheckConformance)
+    if (!IsFirstPass)
       checkExplicitConformance(OOD, OOD->getDeclaredType(),
                                OOD->getInherited());
   }
 
   void visitStructDecl(StructDecl *SD) {
-    if (IsSecondPass)
+    if (IsSecondPass) {
+      for (Decl *Member : SD->getMembers())
+        visit(Member);
+
+      checkExplicitConformance(SD, SD->getDeclaredType(),
+                               SD->getInherited());
       return;
+    }
 
-    bool CheckConformance;
-    checkInherited(SD, SD->getDeclaredType(), SD->getInherited(),
-                   CheckConformance);
+    checkInherited(SD, SD->getDeclaredType(), SD->getInherited());
 
     for (Decl *Member : SD->getMembers()) {
       visit(Member);
@@ -226,24 +226,28 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
     cast<OneOfElementDecl>(SD->getMembers().back())->setType(CreateTy);
     cast<OneOfElementDecl>(SD->getMembers().back())->setArgumentType(TT);
 
-    if (CheckConformance)
+    if (!IsFirstPass)
       checkExplicitConformance(SD, SD->getDeclaredType(),
                                SD->getInherited());
   }
 
   void visitClassDecl(ClassDecl *CD) {
-    if (IsSecondPass)
+    if (IsSecondPass) {
+      for (Decl *Member : CD->getMembers())
+        visit(Member);
+
+      checkExplicitConformance(CD, CD->getDeclaredType(),
+                               CD->getInherited());
       return;
+    }
 
-    bool CheckConformance;
-    checkInherited(CD, CD->getDeclaredType(), CD->getInherited(),
-                   CheckConformance);
+    checkInherited(CD, CD->getDeclaredType(), CD->getInherited());
 
     for (Decl *Member : CD->getMembers()) {
       visit(Member);
     }
 
-    if (CheckConformance)
+    if (!IsFirstPass)
       checkExplicitConformance(CD, CD->getDeclaredType(),
                                CD->getInherited());
   }
@@ -252,9 +256,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
     if (IsSecondPass)
       return;
 
-    bool CheckConformance;
-    checkInherited(PD, PD->getDeclaredType(), PD->getInherited(),
-                   CheckConformance);
+    checkInherited(PD, PD->getDeclaredType(), PD->getInherited());
 
     // Assign archetypes each of the associated types.
     // FIXME: We need to build equivalence classes of associated types first,
@@ -297,6 +299,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
 
     visitValueDecl(FD);
   }
+
   void visitOneOfElementDecl(OneOfElementDecl *ED) {
     if (IsSecondPass)
       return;
@@ -313,11 +316,19 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
                   diag::oneof_element_not_materializable);
     }
   }
+
   void visitExtensionDecl(ExtensionDecl *ED) {
-    if (IsSecondPass)
+    if (IsSecondPass) {
+      for (Decl *Member : ED->getMembers())
+        // First recursively type check each thing in the extension.
+        visit(Member);
+
+      checkExplicitConformance(ED, ED->getExtendedType(),
+                               ED->getInherited());
       return;
+    }
+
 
-    bool CheckConformance;
     if (TC.validateType(ED->getExtendedType(), IsFirstPass)) {
       ED->setExtendedType(ErrorType::get(TC.Context));
     } else {
@@ -330,13 +341,17 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
         // declaration, if any.
       }
 
-      checkInherited(ED, ExtendedTy, ED->getInherited(), CheckConformance);
+      checkInherited(ED, ExtendedTy, ED->getInherited());
     }
 
     for (Decl *Member : ED->getMembers()) {
       // First recursively type check each thing in the extension.
       visit(Member);
     }
+
+    if (!IsFirstPass)
+      checkExplicitConformance(ED, ED->getExtendedType(),
+                               ED->getInherited());
   }
 
   void visitTopLevelCodeDecl(TopLevelCodeDecl *TLCD) {

lib/Sema/TypeCheckStmt.cpp

@@ -686,15 +686,6 @@ static void REPLCheckPatternBinding(PatternBindingDecl *D, TypeChecker &TC) {
   D->setInit(TC.semaApplyExpr(CE));
 }
 
-/// \brief Check for explicit protocol conformance.
-static void checkExplicitConformance(TypeChecker &TC, Decl *D, Type Ty,
-                                     ArrayRef<Type> Inherited) {
-  for (auto InheritedTy : Inherited) {
-    if (ProtocolType *Proto = InheritedTy->getAs<ProtocolType>())
-      TC.conformsToProtocol(Ty, Proto->getDecl(), D->getLocStart());
-  }
-}
-
 /// \brief Check for circular inheritance of protocols.
 ///
 /// \param Path The circular path through the protocol inheritance hierarchy,
@@ -946,21 +937,10 @@ void swift::performTypeChecking(TranslationUnit *TU, unsigned StartElem) {
   // Check for explicit conformance to protocols and for circularity in
   // protocol definitions.
   {
+    // FIXME: This check should be in TypeCheckDecl.
     llvm::SmallPtrSet<ProtocolDecl *, 16> VisitedProtocols;
     for (auto D : TU->Decls) {
-      if (auto Struct = dyn_cast<StructDecl>(D))
-        checkExplicitConformance(TC, Struct, Struct->getDeclaredType(),
-                                 Struct->getInherited());
-      else if (auto Class = dyn_cast<ClassDecl>(D))
-        checkExplicitConformance(TC, Class, Class->getDeclaredType(),
-                                 Class->getInherited());
-      else if (auto OneOf = dyn_cast<OneOfDecl>(D))
-        checkExplicitConformance(TC, OneOf, OneOf->getDeclaredType(),
-                                 OneOf->getInherited());
-      else if (auto Extension = dyn_cast<ExtensionDecl>(D))
-        checkExplicitConformance(TC, Extension, Extension->getExtendedType(),
-                                 Extension->getInherited());
-      else if (auto Protocol = dyn_cast<ProtocolDecl>(D)) {
+      if (auto Protocol = dyn_cast<ProtocolDecl>(D)) {
         // Check for circular protocol definitions.
         llvm::SmallPtrSet<ProtocolDecl *, 16> LocalVisited;
         llvm::SmallVector<ProtocolDecl *, 4> Path;

test/protocols_in_library.swift

@@ -0,0 +1,15 @@
+// RUN: %swift -parse %s -verify -parse-as-library
+
+struct X {
+  struct Inner : Proto {
+  }
+  struct Inner2 : Proto2 { // expected-error {{type 'Inner2' does not conform to protocol 'Proto2'}}
+  }
+}
+
+protocol Proto {
+}
+
+protocol Proto2 {
+  func f() // expected-note {{protocol requires function 'f' with type '() -> ()'}}
+}