get codegen working on GenericMap example

compiler/src/main/cpp/capnpc-java.c++

@@ -1186,8 +1186,17 @@ private:
       kj::String defaultParams = defaultOffset == 0 ? kj::str("null, 0") : kj::str(
         "Schemas.b_", kj::hex(typeId), ", ", defaultOffset);
 
+      auto typeParamVec = getTypeParameters(field.getContainingStruct());
       kj::String listFactory = makeFactoryArg(field.getType());
 
+      bool isGeneric = false;
+      {
+        auto type = field.getType().asList().getElementType();
+        if (type.isStruct()) {
+          isGeneric = type.asStruct().getProto().getIsGeneric();
+        }
+      }
+
       return FieldText {
         kj::strTree(
             kj::mv(unionDiscrim.readerIsDef),
@@ -1195,10 +1204,28 @@ private:
             spaces(indent), "    return !_pointerFieldIsNull(", offset, ");\n",
             spaces(indent), "  }\n",
 
+            (isGeneric ?
+             kj::strTree(
+               spaces(indent), "  public final ",
+               (typeParamVec.size() == 0 ? kj::strTree() :
+                kj::strTree(
+                  "<",
+                  kj::StringTree(KJ_MAP(p, typeParamVec) {
+                      return kj::strTree(p, "_Builder");
+                    }, ", "),
+                  "> ")),
+               readerType,
+               " get", titleCase, "( org.capnproto.ListFactory<", builderType, ", ", readerType, "> factory) {\n",
+               spaces(indent), "    return _getPointerField(factory,", offset, ");\n",
+               spaces(indent), "  }\n"
+               ) :
+             kj::strTree(
                spaces(indent), "  public final ", readerType,
                " get", titleCase, "() {\n",
                spaces(indent), "    return _getPointerField(", listFactory, ", ", offset, ", ", defaultParams, ");\n",
-            spaces(indent), "  }\n",
+               spaces(indent), "  }\n"
+               )
+              ),
             "\n"),
 
         kj::strTree(
@@ -1207,19 +1234,75 @@ private:
             spaces(indent), "    return !_pointerFieldIsNull(", offset, ");\n",
             spaces(indent), "  }\n",
 
+            (isGeneric ?
+             kj::strTree(
+               spaces(indent), "  public final ",
+               (typeParamVec.size() == 0 ? kj::strTree() :
+                kj::strTree(
+                  "<",
+                  kj::StringTree(KJ_MAP(p, typeParamVec) {
+                      return kj::strTree(p, "_Reader");
+                    }, ", "),
+                  "> ")),
+               builderType,
+               " get", titleCase, "( org.capnproto.ListFactory<", builderType, ", ", readerType, "> factory) {\n",
+               spaces(indent), "    return _getPointerField(factory,", offset, ");\n",
+               spaces(indent), "  }\n"
+               ) :
+             kj::strTree(
                spaces(indent), "  public final ", builderType,
                " get", titleCase, "() {\n",
                spaces(indent), "    return _getPointerField(", listFactory, ", ", offset, ", ", defaultParams, ");\n",
-            spaces(indent), "  }\n",
+               spaces(indent), "  }\n"
+               )
+              ),
 
+            (isGeneric ?
+             kj::strTree(
+               spaces(indent), "  public final ",
+               (typeParamVec.size() == 0 ? kj::strTree() :
+                kj::strTree(
+                  "<",
+                  kj::StringTree(KJ_MAP(p, typeParamVec) {
+                      return kj::strTree(p, "_Reader");
+                    }, ", "),
+                  "> ")),
+               "void set", titleCase,
+               "(org.capnproto.SetPointerBuilder<", builderType, ", ", readerType, "> factory, ", readerType, " value) {\n",
+               spaces(indent), "    _setPointerField(factory, ", offset, ", value);\n",
+               spaces(indent), "  }\n"
+               ) :
+             kj::strTree(
                spaces(indent), "  public final void set", titleCase, "(", readerType, " value) {\n",
                spaces(indent), "    _setPointerField(", listFactory, ", ", offset, ", value);\n",
-            spaces(indent), "  }\n",
+               spaces(indent), "  }\n"
+               )
+              ),
 
+            (isGeneric ?
+             kj::strTree(
+               spaces(indent), "  public final ",
+               (typeParamVec.size() == 0 ? kj::strTree() :
+                kj::strTree(
+                  "<",
+                  kj::StringTree(KJ_MAP(p, typeParamVec) {
+                      return kj::strTree(p, "_Reader");
+                    }, ", "),
+                  "> ")),
+               builderType,
+               " init", titleCase, "( org.capnproto.ListFactory<", builderType, ", ", readerType, "> factory, int size) {\n",
+               spaces(indent), "    return _initPointerField(factory, ", offset, ", size);\n",
+               spaces(indent), "  }\n"
+               ) :
+             kj::strTree(
                spaces(indent), "  public final ", builderType,
                " init", titleCase, "(int size) {\n",
                spaces(indent), "    return _initPointerField(", listFactory, ", ", offset, ", size);\n",
-            spaces(indent), "  }\n"),
+               spaces(indent), "  }\n")
+              )
+          ),
+
+
       };
     } else {
       KJ_UNREACHABLE;

compiler/src/test/scala/org/capnproto/EncodingSuite.scala

@@ -609,6 +609,47 @@ class EncodingSuite extends FunSuite {
     TestUtil.checkTestMessage(field.asReader())
   }
 
+  test("GenericMap") {
+    val builder = new MessageBuilder()
+    val mapFactory = new GenericMap.Factory(Text.factory, TestAllTypes.factory)
+    val entryFactory = new StructList.Factory(new GenericMap.Entry.Factory(Text.factory, TestAllTypes.factory));
+    val root = builder.initRoot(mapFactory)
+
+    {
+      val entries = root.initEntries(entryFactory, 3);
+
+      val entry0 = entries.get(0)
+      entry0.setKey(Text.factory, new Text.Reader("foo"))
+      val value0 = entry0.initValue()
+      value0.setInt64Field(101);
+
+      val entry1 = entries.get(1)
+      entry1.setKey(Text.factory, new Text.Reader("bar"))
+      val value1 = entry1.initValue()
+      value1.setInt64Field(202);
+
+      val entry2 = entries.get(2)
+      entry2.setKey(Text.factory, new Text.Reader("baz"))
+      val value2 = entry2.initValue()
+      value2.setInt64Field(303);
+    }
+
+    {
+      val entries = root.asReader(mapFactory).getEntries(entryFactory)
+      val entry0 = entries.get(0)
+      assert(entry0.getKey().toString() == "foo")
+      assert(entry0.getValue().getInt64Field() == 101)
+
+      val entry1 = entries.get(1)
+      assert(entry1.getKey().toString() == "bar")
+      assert(entry1.getValue().getInt64Field() == 202)
+
+      val entry2 = entries.get(2)
+      assert(entry2.getKey().toString() == "baz")
+      assert(entry2.getValue().getInt64Field == 303)
+    }
+  }
+
   // to debug, do this:
   //Serialize.write((new java.io.FileOutputStream("/Users/dwrensha/Desktop/test.dat")).getChannel(),
   //                 message)

compiler/src/test/schema/test.capnp

@@ -377,6 +377,16 @@ struct TestUseGenerics  {
   listOfGenerics @11 :List(TestGenerics(TestAllTypes, Text));
 }
 
+struct GenericMap(K, V)
+{
+  entries @0 :List(Entry);
+
+  struct Entry
+  {
+    key @0 :K;
+    value @1 :V;
+  }
+}
 
 struct TestEmptyStruct {}