Sema: More consistent logic for non-requirement protocol members

Ajisaputrars · Dec 21, 2016 · 978941f · 978941f
1 parent 3f7a72e
commit 978941f
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Showing 5 changed files with 27 additions and 23 deletions.
diff --git a/lib/Sema/TypeCheckNameLookup.cpp b/lib/Sema/TypeCheckNameLookup.cpp
@@ -150,7 +150,7 @@ namespace {
         }
 
         // Dig out the witness.
-        ValueDecl *witness;
+        ValueDecl *witness = nullptr;
         auto concrete = conformance->getConcrete();
         if (auto assocType = dyn_cast<AssociatedTypeDecl>(found)) {
           // If we're validating the protocol recursively, bail out.
@@ -159,14 +159,7 @@ namespace {
 
           witness = concrete->getTypeWitnessSubstAndDecl(assocType, &TC)
             .second;
-        } else if (isa<TypeAliasDecl>(found)) {
-          // No witness for typealiases. This means typealiases in
-          // protocols cannot be found if PerformConformanceCheck
-          // is on.
-          //
-          // FIXME: Fix this.
-          return;
-        } else {
+        } else if (TC.isRequirement(found)) {
           witness = concrete->getWitness(found, &TC).getDecl();
         }
 

diff --git a/lib/Sema/TypeCheckProtocol.cpp b/lib/Sema/TypeCheckProtocol.cpp
@@ -3969,17 +3969,6 @@ void ConformanceChecker::resolveSingleTypeWitness(
   }
 }
 
-// Not all protocol members are requirements.
-static bool isRequirement(ValueDecl *requirement) {
-  if (auto *FD = dyn_cast<FuncDecl>(requirement))
-    if (FD->isAccessor())
-      return false;
-  if (isa<TypeAliasDecl>(requirement) ||
-      isa<NominalTypeDecl>(requirement))
-    return false;
-  return true;
-}
-
 void ConformanceChecker::resolveSingleWitness(ValueDecl *requirement) {
   assert(!isa<AssociatedTypeDecl>(requirement) && "Not a value witness");
   assert(!Conformance->hasWitness(requirement) && "Already resolved");
@@ -3998,7 +3987,7 @@ void ConformanceChecker::resolveSingleWitness(ValueDecl *requirement) {
     return;
   }
 
-  if (!isRequirement(requirement))
+  if (!TC.isRequirement(requirement))
     return;
 
   // Resolve all associated types before trying to resolve this witness.
@@ -4147,7 +4136,7 @@ void ConformanceChecker::checkConformance() {
       continue;
 
     // Type aliases don't have requirements themselves.
-    if (!isRequirement(requirement))
+    if (!TC.isRequirement(requirement))
       continue;
 
     /// Local function to finalize the witness.
@@ -5564,6 +5553,17 @@ void DefaultWitnessChecker::recordWitness(
                                         storage);
 }
 
+// Not all protocol members are requirements.
+bool TypeChecker::isRequirement(ValueDecl *requirement) {
+  if (auto *FD = dyn_cast<FuncDecl>(requirement))
+    if (FD->isAccessor())
+      return false;
+  if (isa<TypeAliasDecl>(requirement) ||
+      isa<NominalTypeDecl>(requirement))
+    return false;
+  return true;
+}
+
 void TypeChecker::inferDefaultWitnesses(ProtocolDecl *proto) {
   DefaultWitnessChecker checker(*this, proto);
 

diff --git a/lib/Sema/TypeChecker.h b/lib/Sema/TypeChecker.h
@@ -1000,6 +1000,9 @@ class TypeChecker final : public LazyResolver {
   /// Introduce the accessors for a 'lazy' variable.
   void introduceLazyVarAccessors(VarDecl *var) override;
 
+  // Not all protocol members are requirements.
+  bool isRequirement(ValueDecl *requirement);
+
   /// Infer default value witnesses for all requirements in the given protocol.
   void inferDefaultWitnesses(ProtocolDecl *proto);
 

diff --git a/test/decl/nested/protocol.swift b/test/decl/nested/protocol.swift
@@ -22,12 +22,20 @@ class OuterGenericClass<T> {
 protocol OuterProtocol {
   associatedtype Hen
   protocol InnerProtocol { // expected-error{{protocol 'InnerProtocol' cannot be nested inside another declaration}}
+  // expected-note@-1 {{did you mean 'InnerProtocol'?}}
     associatedtype Rooster
     func flip(_ r: Rooster)
     func flop(_ h: Hen)
   }
 }
 
+struct ConformsToOuterProtocol : OuterProtocol {
+  typealias Hen = Int
+
+  func f() { let _ = InnerProtocol.self }
+  // expected-error@-1 {{use of unresolved identifier 'InnerProtocol'}}
+}
+
 protocol Racoon {
   associatedtype Stripes
   class Claw<T> { // expected-error{{type 'Claw' cannot be nested in protocol 'Racoon'}}

diff --git a/...esolver-did-not-resolve-requirement.swift → ...esolver-did-not-resolve-requirement.swift b/...esolver-did-not-resolve-requirement.swift → ...esolver-did-not-resolve-requirement.swift
@@ -5,6 +5,6 @@
 // See https://swift.org/LICENSE.txt for license information
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
-// RUN: not --crash %target-swift-frontend %s -emit-ir
+// RUN: not %target-swift-frontend %s -emit-ir
 // REQUIRES: asserts
 class d:A{var f{{_=A{}}}}protocol A{protocol A