TopoSorter: Sort Typedefs before pointers

Also rename visitAfter() to acceptAfter() to match the previous renaming
of visit() to accept().

oi/type_graph/TopoSorter.cpp

@@ -69,7 +69,7 @@ void TopoSorter::visit(Class& c) {
   // Same as pointers, children do not create a dependency so are delayed until
   // the end.
   for (const auto& child : c.children) {
-    visitAfter(child);
+    acceptAfter(child);
   }
 }
 
@@ -103,7 +103,7 @@ void TopoSorter::visit(Container& c) {
   sortedTypes_.push_back(c);
   if (containerAllowsIncompleteParams(c)) {
     for (const auto& param : c.templateParams) {
-      visitAfter(param.type());
+      acceptAfter(param.type());
     }
   }
 }
@@ -118,9 +118,16 @@ void TopoSorter::visit(Typedef& td) {
 }
 
 void TopoSorter::visit(Pointer& p) {
+  if (dynamic_cast<Typedef*>(&p.pointeeType())) {
+    // Typedefs can not be forward declared, so we must sort them before
+    // pointers which reference them
+    accept(p.pointeeType());
+    return;
+  }
+
   // Pointers do not create a dependency, but we do still care about the types
   // they point to, so delay them until the end.
-  visitAfter(p.pointeeType());
+  acceptAfter(p.pointeeType());
 }
 
 /*
@@ -131,13 +138,13 @@ void TopoSorter::visit(Pointer& p) {
  * program. This means we can delay processing them until after all of the true
  * dependencies have been sorted.
  */
-void TopoSorter::visitAfter(Type& type) {
+void TopoSorter::acceptAfter(Type& type) {
   typesToSort_.push(type);
 }
 
-void TopoSorter::visitAfter(Type* type) {
+void TopoSorter::acceptAfter(Type* type) {
   if (type) {
-    visitAfter(*type);
+    acceptAfter(*type);
   }
 }
 

oi/type_graph/TopoSorter.h

@@ -52,8 +52,8 @@ class TopoSorter : public RecursiveVisitor {
   std::vector<std::reference_wrapper<Type>> sortedTypes_;
   std::queue<std::reference_wrapper<Type>> typesToSort_;
 
-  void visitAfter(Type& type);
-  void visitAfter(Type* type);
+  void acceptAfter(Type& type);
+  void acceptAfter(Type* type);
 };
 
 }  // namespace type_graph

test/test_topo_sorter.cpp

@@ -209,10 +209,16 @@ aliasA
 
 TEST(TopoSorterTest, Pointers) {
   // Pointers do not require pointee types to be defined first
-  auto myclass = Class{0, Class::Kind::Class, "MyClass", 69};
-  auto mypointer = Pointer{1, myclass};
+  auto classA = Class{0, Class::Kind::Class, "ClassA", 69};
+  auto mypointer = Pointer{1, classA};
 
-  test({mypointer}, "MyClass");
+  auto myclass = Class{2, Class::Kind::Class, "MyClass", 69};
+  myclass.members.push_back(Member{mypointer, "ptr", 0});
+
+  test({myclass}, R"(
+MyClass
+ClassA
+)");
 }
 
 TEST(TopoSorterTest, PointerCycle) {
@@ -238,6 +244,22 @@ ClassA
   }
 }
 
+TEST(TopoSorterTest, PointerToTypedef) {
+  auto classA = Class{0, Class::Kind::Class, "ClassA", 8};
+  auto aliasA = Typedef{1, "aliasA", classA};
+
+  auto mypointer = Pointer{1, aliasA};
+
+  auto myclass = Class{2, Class::Kind::Class, "MyClass", 69};
+  myclass.members.push_back(Member{mypointer, "ptrToTypedef", 0});
+
+  test({myclass}, R"(
+ClassA
+aliasA
+MyClass
+)");
+}
+
 TEST(TopoSorterTest, TwoDeep) {
   auto myunion = Class{0, Class::Kind::Union, "MyUnion", 7};
   auto mystruct = Class{1, Class::Kind::Struct, "MyStruct", 13};