Have Node's enum and interface fields be groups with a single field, for future expandability.

c++/src/capnp/compiler/capnpc-c++.c++

@@ -98,7 +98,7 @@ void enumerateDeps(schema::Node::Reader node, std::set<uint64_t>& deps) {
       break;
     }
     case schema::Node::INTERFACE:
-      for (auto method: node.getInterface()) {
+      for (auto method: node.getInterface().getMethods()) {
         for (auto param: method.getParams()) {
           enumerateDeps(param.getType(), deps);
         }

c++/src/capnp/compiler/capnpc-capnp.c++

@@ -262,7 +262,7 @@ private:
       case schema::Value::ENUM: {
         KJ_REQUIRE(type.which() == schema::Type::ENUM, "type/value mismatch");
         auto enumNode = scope.getDependency(type.getEnum()).asEnum().getProto();
-        auto enumerants = enumNode.getEnum();
+        auto enumerants = enumNode.getEnum().getEnumerants();
         KJ_REQUIRE(value.getEnum() < enumerants.size(),
                 "Enum value out-of-range.", value.getEnum(), enumNode.getDisplayName());
         return kj::strTree(enumerants[value.getEnum()].getName());

c++/src/capnp/compiler/compiler.c++

@@ -715,13 +715,13 @@ void Compiler::Node::traverseNodeDependencies(
       break;
 
     case schema::Node::ENUM:
-      for (auto enumerant: schemaNode.getEnum()) {
+      for (auto enumerant: schemaNode.getEnum().getEnumerants()) {
         traverseAnnotations(enumerant.getAnnotations(), eagerness, seen);
       }
       break;
 
     case schema::Node::INTERFACE:
-      for (auto method: schemaNode.getInterface()) {
+      for (auto method: schemaNode.getInterface().getMethods()) {
         for (auto param: method.getParams()) {
           traverseType(param.getType(), eagerness, seen);
           traverseAnnotations(param.getAnnotations(), eagerness, seen);

c++/src/capnp/compiler/node-translator.c++

@@ -761,7 +761,7 @@ void NodeTranslator::compileEnum(Void decl,
     }
   }
 
-  auto list = builder.initEnum(enumerants.size());
+  auto list = builder.initEnum().initEnumerants(enumerants.size());
   uint i = 0;
   DuplicateOrdinalDetector dupDetector(errorReporter);
 

c++/src/capnp/schema-loader.c++

@@ -351,7 +351,8 @@ private:
     }
   }
 
-  void validate(const List<schema::Enumerant>::Reader& enumerants) {
+  void validate(const schema::Node::Enum::Reader& enumNode) {
+    auto enumerants = enumNode.getEnumerants();
     KJ_STACK_ARRAY(bool, sawCodeOrder, enumerants.size(), 32, 256);
     memset(sawCodeOrder.begin(), 0, sawCodeOrder.size() * sizeof(sawCodeOrder[0]));
 
@@ -366,7 +367,8 @@ private:
     }
   }
 
-  void validate(const List<schema::Method>::Reader& methods) {
+  void validate(const schema::Node::Interface::Reader& interfaceNode) {
+    auto methods = interfaceNode.getMethods();
     KJ_STACK_ARRAY(bool, sawCodeOrder, methods.size(), 32, 256);
     memset(sawCodeOrder.begin(), 0, sawCodeOrder.size() * sizeof(sawCodeOrder[0]));
 
@@ -694,10 +696,10 @@ private:
     }
   }
 
-  void checkCompatibility(const List<schema::Enumerant>::Reader& enumerants,
-                          const List<schema::Enumerant>::Reader& replacementEnumerants) {
-    uint size = enumerants.size();
-    uint replacementSize = replacementEnumerants.size();
+  void checkCompatibility(const schema::Node::Enum::Reader& enumNode,
+                          const schema::Node::Enum::Reader& replacement) {
+    uint size = enumNode.getEnumerants().size();
+    uint replacementSize = replacement.getEnumerants().size();
     if (replacementSize > size) {
       replacementIsNewer();
     } else if (replacementSize < size) {
@@ -705,8 +707,11 @@ private:
     }
   }
 
-  void checkCompatibility(const List<schema::Method>::Reader& methods,
-                          const List<schema::Method>::Reader& replacementMethods) {
+  void checkCompatibility(const schema::Node::Interface::Reader& interfaceNode,
+                          const schema::Node::Interface::Reader& replacement) {
+    auto methods = interfaceNode.getMethods();
+    auto replacementMethods = replacement.getMethods();
+
     if (replacementMethods.size() > methods.size()) {
       replacementIsNewer();
     } else if (replacementMethods.size() < methods.size()) {
@@ -1169,8 +1174,8 @@ _::RawSchema* SchemaLoader::Impl::loadEmpty(
   node.setDisplayName(name);
   switch (kind) {
     case schema::Node::STRUCT: node.initStruct(); break;
-    case schema::Node::ENUM: node.initEnum(0); break;
-    case schema::Node::INTERFACE: node.initInterface(0); break;
+    case schema::Node::ENUM: node.initEnum(); break;
+    case schema::Node::INTERFACE: node.initInterface(); break;
 
     case schema::Node::FILE:
     case schema::Node::CONST:

c++/src/capnp/schema-test.c++

@@ -131,7 +131,7 @@ TEST(Schema, Enums) {
   EXPECT_TRUE(schema.asEnum() == schema);
 
   ASSERT_EQ(schema.getEnumerants().size(),
-            schema.getProto().getEnum().size());
+            schema.getProto().getEnum().getEnumerants().size());
   EnumSchema::Enumerant enumerant = schema.getEnumerants()[0];
   EXPECT_EQ("foo", enumerant.getProto().getName());
   EXPECT_TRUE(enumerant.getContainingEnum() == schema);

c++/src/capnp/schema.c++

@@ -189,7 +189,7 @@ uint32_t StructSchema::Field::getDefaultValueSchemaOffset() const {
 // -------------------------------------------------------------------
 
 EnumSchema::EnumerantList EnumSchema::getEnumerants() const {
-  return EnumerantList(*this, getProto().getEnum());
+  return EnumerantList(*this, getProto().getEnum().getEnumerants());
 }
 
 kj::Maybe<EnumSchema::Enumerant> EnumSchema::findEnumerantByName(kj::StringPtr name) const {
@@ -207,7 +207,7 @@ EnumSchema::Enumerant EnumSchema::getEnumerantByName(kj::StringPtr name) const {
 // -------------------------------------------------------------------
 
 InterfaceSchema::MethodList InterfaceSchema::getMethods() const {
-  return MethodList(*this, getProto().getInterface());
+  return MethodList(*this, getProto().getInterface().getMethods());
 }
 
 kj::Maybe<InterfaceSchema::Method> InterfaceSchema::findMethodByName(kj::StringPtr name) const {

c++/src/capnp/schema.capnp

@@ -120,11 +120,15 @@ struct Node {
       # most sense to use the field's index in this list rather than its ordinal.
     }
 
-    enum @14 :List(Enumerant);
+    enum :group {
+      enumerants@14 :List(Enumerant);
       # Enumerants ordered by numeric value (ordinal).
+    }
 
-    interface @15 :List(Method);
+    interface :group {
+      methods @15 :List(Method);
       # Methods ordered by ordinal.
+    }
 
     const :group {
       type @16 :Type;

c++/src/capnp/schema.capnp.c++

@@ -5,7 +5,7 @@
 
 namespace capnp {
 namespace schemas {
-static const ::capnp::_::AlignedData<189> b_e682ab4cf923a417 = {
+static const ::capnp::_::AlignedData<171> b_e682ab4cf923a417 = {
   {   0,   0,   0,   0,   5,   0,   5,   0,
      23, 164,  35, 249,  76, 171, 130, 230,
       0,   0,   0,   0,   1,   0,   5,   0,
@@ -82,31 +82,31 @@ static const ::capnp::_::AlignedData<189> b_e682ab4cf923a417 = {
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
-      8,   0, 253, 255,   3,   0,   0,   0,
-      0,   0,   1,   0,  14,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
+      8,   0, 253, 255,   0,   0,   0,   0,
+      1,   0,   0,   0,   0,   0,   0,   0,
+    152, 245,  51,  67,  54, 179,  74, 181,
      85,   1,   0,   0,  42,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
-     80,   1,   0,   0,   2,   0,   1,   0,
-    100,   1,   0,   0,   2,   0,   1,   0,
-      9,   0, 252, 255,   3,   0,   0,   0,
-      0,   0,   1,   0,  15,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
-     97,   1,   0,   0,  82,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
-     96,   1,   0,   0,   2,   0,   1,   0,
-    116,   1,   0,   0,   2,   0,   1,   0,
+      9,   0, 252, 255,   0,   0,   0,   0,
+      1,   0,   0,   0,   0,   0,   0,   0,
+    143,  33, 194, 240, 207,  83,  39, 232,
+     61,   1,   0,   0,  82,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
      10,   0, 251, 255,   0,   0,   0,   0,
       1,   0,   0,   0,   0,   0,   0,   0,
      32, 148,  13, 122, 172, 165, 138, 177,
-    113,   1,   0,   0,  50,   0,   0,   0,
+     41,   1,   0,   0,  50,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
      11,   0, 250, 255,   0,   0,   0,   0,
       1,   0,   0,   0,   0,   0,   0,   0,
     144,   2,  10,  64, 212,  25,  22, 236,
-     89,   1,   0,   0,  90,   0,   0,   0,
+     17,   1,   0,   0,  90,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
       0,   0,   0,   0,   0,   0,   0,   0,
@@ -172,43 +172,25 @@ static const ::capnp::_::AlignedData<189> b_e682ab4cf923a417 = {
       0,   0,   0,   0,   0,   0,   0,   0,
     115, 116, 114, 117,  99, 116,   0,   0,
     101, 110, 117, 109,   0,   0,   0,   0,
-     14,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   2,   0,   1,   0,
-     16,   0,   0,   0,   0,   0,   0,   0,
-     77, 154,  84, 220, 235, 124, 138, 151,
-      0,   0,   0,   0,   0,   0,   0,   0,
-     14,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
     105, 110, 116, 101, 114, 102,  97,  99,
     101,   0,   0,   0,   0,   0,   0,   0,
-     14,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   2,   0,   1,   0,
-     16,   0,   0,   0,   0,   0,   0,   0,
-    128,  77,  51,  59, 226, 204,   0, 149,
-      0,   0,   0,   0,   0,   0,   0,   0,
-     14,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
-      0,   0,   0,   0,   0,   0,   0,   0,
      99, 111, 110, 115, 116,   0,   0,   0,
      97, 110, 110, 111, 116,  97, 116, 105,
     111, 110,   0,   0,   0,   0,   0,   0, }
 };
 static const ::capnp::_::RawSchema* const d_e682ab4cf923a417[] = {
-  &s_9500cce23b334d80,
-  &s_978a7cebdc549a4d,
   &s_9ea0b19b37fb4435,
   &s_b18aa5ac7a0d9420,
+  &s_b54ab3364333f598,
   &s_debf55bbfa0fc242,
+  &s_e82753cff0c2218f,
   &s_ec1619d4400a0290,
   &s_f1c8950dab257542,
 };
 static const uint16_t m_e682ab4cf923a417[] = {11, 5, 10, 1, 2, 8, 6, 0, 9, 4, 3, 7};
 static const uint16_t i_e682ab4cf923a417[] = {6, 7, 8, 9, 10, 11, 0, 1, 2, 3, 4, 5};
 const ::capnp::_::RawSchema s_e682ab4cf923a417 = {
-  0xe682ab4cf923a417, b_e682ab4cf923a417.words, 189, d_e682ab4cf923a417, m_e682ab4cf923a417,
+  0xe682ab4cf923a417, b_e682ab4cf923a417.words, 171, d_e682ab4cf923a417, m_e682ab4cf923a417,
   7, 12, i_e682ab4cf923a417, nullptr, nullptr
 };
 static const ::capnp::_::AlignedData<46> b_debf55bbfa0fc242 = {
@@ -407,6 +389,98 @@ const ::capnp::_::RawSchema s_9ea0b19b37fb4435 = {
   0x9ea0b19b37fb4435, b_9ea0b19b37fb4435.words, 127, d_9ea0b19b37fb4435, m_9ea0b19b37fb4435,
   3, 7, i_9ea0b19b37fb4435, nullptr, nullptr
 };
+static const ::capnp::_::AlignedData<34> b_b54ab3364333f598 = {
+  {   0,   0,   0,   0,   5,   0,   5,   0,
+    152, 245,  51,  67,  54, 179,  74, 181,
+     24,   0,   0,   0,   1,   0,   5,   0,
+     23, 164,  35, 249,  76, 171, 130, 230,
+      5,   0,   7,   0,   1,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     17,   0,   0,   0, 234,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     21,   0,   0,   0,  63,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     99,  97, 112, 110, 112,  47, 115,  99,
+    104, 101, 109,  97,  46,  99,  97, 112,
+    110, 112,  58,  78, 111, 100, 101,  46,
+    101, 110, 117, 109,   0,   0,   0,   0,
+      4,   0,   0,   0,   3,   0,   4,   0,
+      0,   0,   0,   0,   3,   0,   0,   0,
+      0,   0,   1,   0,  14,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     13,   0,   0,   0,  90,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     12,   0,   0,   0,   2,   0,   1,   0,
+     32,   0,   0,   0,   2,   0,   1,   0,
+    101, 110, 117, 109, 101, 114,  97, 110,
+    116, 115,   0,   0,   0,   0,   0,   0,
+     14,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   2,   0,   1,   0,
+     16,   0,   0,   0,   0,   0,   0,   0,
+     77, 154,  84, 220, 235, 124, 138, 151,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     14,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0, }
+};
+static const ::capnp::_::RawSchema* const d_b54ab3364333f598[] = {
+  &s_978a7cebdc549a4d,
+  &s_e682ab4cf923a417,
+};
+static const uint16_t m_b54ab3364333f598[] = {0};
+static const uint16_t i_b54ab3364333f598[] = {0};
+const ::capnp::_::RawSchema s_b54ab3364333f598 = {
+  0xb54ab3364333f598, b_b54ab3364333f598.words, 34, d_b54ab3364333f598, m_b54ab3364333f598,
+  2, 1, i_b54ab3364333f598, nullptr, nullptr
+};
+static const ::capnp::_::AlignedData<34> b_e82753cff0c2218f = {
+  {   0,   0,   0,   0,   5,   0,   5,   0,
+    143,  33, 194, 240, 207,  83,  39, 232,
+     24,   0,   0,   0,   1,   0,   5,   0,
+     23, 164,  35, 249,  76, 171, 130, 230,
+      5,   0,   7,   0,   1,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     17,   0,   0,   0,  18,   1,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     25,   0,   0,   0,  63,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     99,  97, 112, 110, 112,  47, 115,  99,
+    104, 101, 109,  97,  46,  99,  97, 112,
+    110, 112,  58,  78, 111, 100, 101,  46,
+    105, 110, 116, 101, 114, 102,  97,  99,
+    101,   0,   0,   0,   0,   0,   0,   0,
+      4,   0,   0,   0,   3,   0,   4,   0,
+      0,   0,   0,   0,   3,   0,   0,   0,
+      0,   0,   1,   0,  15,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     13,   0,   0,   0,  66,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      8,   0,   0,   0,   2,   0,   1,   0,
+     28,   0,   0,   0,   2,   0,   1,   0,
+    109, 101, 116, 104, 111, 100, 115,   0,
+     14,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   2,   0,   1,   0,
+     16,   0,   0,   0,   0,   0,   0,   0,
+    128,  77,  51,  59, 226, 204,   0, 149,
+      0,   0,   0,   0,   0,   0,   0,   0,
+     14,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0,
+      0,   0,   0,   0,   0,   0,   0,   0, }
+};
+static const ::capnp::_::RawSchema* const d_e82753cff0c2218f[] = {
+  &s_9500cce23b334d80,
+  &s_e682ab4cf923a417,
+};
+static const uint16_t m_e82753cff0c2218f[] = {0};
+static const uint16_t i_e82753cff0c2218f[] = {0};
+const ::capnp::_::RawSchema s_e82753cff0c2218f = {
+  0xe82753cff0c2218f, b_e82753cff0c2218f.words, 34, d_e82753cff0c2218f, m_e82753cff0c2218f,
+  2, 1, i_e82753cff0c2218f, nullptr, nullptr
+};
 static const ::capnp::_::AlignedData<44> b_b18aa5ac7a0d9420 = {
   {   0,   0,   0,   0,   5,   0,   5,   0,
      32, 148,  13, 122, 172, 165, 138, 177,
@@ -2161,6 +2235,10 @@ CAPNP_DEFINE_STRUCT(
     ::capnp::schema::Node::NestedNode);
 CAPNP_DEFINE_STRUCT(
     ::capnp::schema::Node::Struct);
+CAPNP_DEFINE_STRUCT(
+    ::capnp::schema::Node::Enum);
+CAPNP_DEFINE_STRUCT(
+    ::capnp::schema::Node::Interface);
 CAPNP_DEFINE_STRUCT(
     ::capnp::schema::Node::Const);
 CAPNP_DEFINE_STRUCT(