fix(cpp): do not generate *.pc.{h,cc} for no-data-sheet proto, remove unused variable

cmd/protoc-gen-cpp-tableau-loader/embed/load.pc.cc

@@ -63,7 +63,6 @@ bool PatchMessage(google::protobuf::Message& dst, const google::protobuf::Messag
       // Reference:
       // https://github.com/protocolbuffers/protobuf/blob/95ef4134d3f65237b7adfb66e5e7aa10fcfa1fa3/src/google/protobuf/map_field.cc#L500
       auto key_fd = fd->message_type()->map_key();
-      auto value_fd = fd->message_type()->map_value();
       int src_count = src_reflection->FieldSize(src, fd);
       int dst_count = dst_reflection->FieldSize(dst, fd);
       switch (key_fd->cpp_type()) {

cmd/protoc-gen-cpp-tableau-loader/hub.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/iancoleman/strcase"
 	"github.com/tableauio/loader/cmd/protoc-gen-cpp-tableau-loader/helper"
+	"github.com/tableauio/loader/internal/options"
 	"github.com/tableauio/tableau/proto/tableaupb"
 	"google.golang.org/protobuf/compiler/protogen"
 	"google.golang.org/protobuf/proto"
@@ -15,7 +16,7 @@ import (
 func getAllOrderedFilesAndMessagers(gen *protogen.Plugin) (protofiles []string, fileMessagers map[string][]string) {
 	fileMessagers = map[string][]string{}
 	for _, f := range gen.Files {
-		if !f.Generate {
+		if !options.NeedGenFile(f) {
 			continue
 		}
 		opts := f.Desc.Options().(*descriptorpb.FileOptions)

test/cpp-tableau-loader/src/protoconf/load.pc.cc

@@ -68,7 +68,6 @@ bool PatchMessage(google::protobuf::Message& dst, const google::protobuf::Messag
       // Reference:
       // https://github.com/protocolbuffers/protobuf/blob/95ef4134d3f65237b7adfb66e5e7aa10fcfa1fa3/src/google/protobuf/map_field.cc#L500
       auto key_fd = fd->message_type()->map_key();
-      auto value_fd = fd->message_type()->map_value();
       int src_count = src_reflection->FieldSize(src, fd);
       int dst_count = dst_reflection->FieldSize(dst, fd);
       switch (key_fd->cpp_type()) {

test/proto/union_conf.proto

@@ -0,0 +1,44 @@
+syntax = "proto3";
+
+package protoconf;
+
+import "tableau/protobuf/tableau.proto";
+
+option go_package = "github.com/tableauio/loader/test/go-tableau-loader/protoconf";
+option (tableau.workbook) = {
+  name: "Union.xlsx"
+};
+
+message HeroTarget {
+  option (tableau.union) = {
+    name: "UnionType"
+    note: "HeroTarget note"
+  };
+
+  Type type = 9999 [(tableau.field) = { name: "Type" }];
+  oneof value {
+    option (tableau.oneof) = {
+      note: "HeroTarget note"
+      field: "Field"
+    };
+
+    StarUp star_up = 1;    // Bound to enum value: TYPE_STAR_UP.
+    LevelUp level_up = 2;  // Bound to enum value: TYPE_LEVEL_UP.
+  }
+
+  enum Type {
+    TYPE_INVALID = 0;
+    TYPE_STAR_UP = 1 [(tableau.evalue).name = "HeroStarUp"];    // HeroStarUp
+    TYPE_LEVEL_UP = 2 [(tableau.evalue).name = "HeroLevelUp"];  // HeroLevelUp
+  }
+
+  message StarUp {
+    uint32 id = 1 [(tableau.field) = { name: "ID" }];
+    int32 star = 2 [(tableau.field) = { name: "Star" }];
+  }
+  message LevelUp {
+    repeated uint32 id_list = 1 [(tableau.field) = { name: "ID" layout: LAYOUT_INCELL }];
+    int32 level = 2 [(tableau.field) = { name: "Level" }];
+    bool super = 3 [(tableau.field) = { name: "Super" }];
+  }
+}