Add TOML support

src/Foundational/iwmisc/BUILD

@@ -1,3 +1,20 @@
+load("@rules_proto//proto:defs.bzl", "proto_library")
+
+proto_library(
+    name = "for_testing_proto",
+    srcs = [
+        "for_testing.proto",
+    ],
+)
+
+cc_proto_library(
+    name = "for_testing_cc_proto",
+    deps = [
+        "for_testing_proto",
+    ]
+)
+
+
 cc_library(
     name = "activity_from_file",
     srcs = [
@@ -86,13 +103,25 @@ cc_library(
     deps = [
         ":internal",
         ":iwconfig",
+        ":ltoml",
         "//Foundational/cmdline:iwcmdline",
         "//Foundational/data_source:iwstring_data_source",
         "//Foundational/iwqsort",
         "@com_google_protobuf//:protobuf",
     ],
 )
 
+cc_library(
+    name = "ltoml",
+    srcs = [
+        "toml_support.h",
+    ],
+    deps = [
+        "@tomlplusplus//:toml++",
+        "@com_google_absl//absl/status:status",
+    ],
+)
+
 cc_library(
     name = "internal",
     hdrs = [
@@ -280,3 +309,17 @@ cc_test(
         "@benchmark//:benchmark_main",
     ],
 )
+
+cc_test(
+    name = "toml_support_test",
+    srcs = [
+        "toml_support_test.cc",
+    ],
+    deps = [
+        "for_testing_cc_proto",
+        ":iwmisc",
+        ":ltoml",
+        "@googletest//:gtest_main",
+        "@tomlplusplus//:toml++",
+    ]
+)

src/Foundational/iwmisc/for_testing.proto

@@ -0,0 +1,24 @@
+syntax = "proto3";
+
+package for_testing;
+
+message SubMessage {
+  optional int32 i1 = 1;
+  optional string str1 = 2;
+}
+
+message TestMessage {
+  optional string str1 = 1;
+  optional string str2 = 2;
+
+  optional int32 i1 = 3;
+  optional uint32 ui1 = 4;
+  optional float x = 5;
+
+  repeated int32 int_array = 6;
+  repeated float float_array = 7;
+
+  repeated string repeated_string = 8;
+
+  optional SubMessage sub_message = 9;
+}

src/Foundational/iwmisc/proto_support.h

@@ -18,6 +18,8 @@
 #include "Foundational/iwmisc/proto_support.h"
 #include "Foundational/iwstring/iwstring.h"
 
+#include "toml_support.h"
+
 namespace iwmisc {
 
 using std::cerr;
@@ -144,6 +146,9 @@ ReadTextProto(IWString& fname) {
   if (fname.ends_with(".json")) {
     return ReadTextProtoJson<Proto>(fname);
   }
+  if (fname.ends_with(".toml")) {
+    return ReadTomlProto<Proto>(fname);
+  }
 
   AFile input(fname, O_RDONLY);
   if (! input.good()) {

src/Foundational/iwmisc/toml_support.h

@@ -0,0 +1,74 @@
+#ifndef FOUNDATIONAL_IWMISC_TOML_SUPPORT_H_
+#define FOUNDATIONAL_IWMISC_TOML_SUPPORT_H_
+
+#include <iostream>
+#include <optional>
+#include <string>
+#include <sstream>
+
+#define TOML_EXCEPTIONS 0 // only necessary if you've left them enabled in your compiler
+#define TOML_ENABLE_FORMATTERS 1
+
+#include "absl/status/status.h"
+
+#include "toml.hpp"
+#include "google/protobuf/util/json_util.h"
+
+#include "Foundational/iwstring/iwstring.h"
+
+namespace iwmisc {
+
+
+template <typename Proto>
+std::optional<Proto>
+TomlToProto(toml::table& tbl) {
+  std::stringstream ss;
+  ss << toml::json_formatter{tbl};
+  const std::string as_json = ss.str();
+
+  Proto proto;
+
+  google::protobuf::util::JsonParseOptions options;
+  auto status = google::protobuf::util::JsonStringToMessage(as_json, &proto, options);
+
+  // cannot figure out how to do error checking properly. I never really understood Status
+  // while I was at Google, still don't.
+  if (status != absl::OkStatus()) {
+    std::cerr << "TomlToProto:cannot parse JSON\n";
+    std::cerr << as_json << '\n';
+    return std::nullopt;
+  }
+
+  return proto;
+}
+
+template <typename Proto>
+std::optional<Proto>
+ReadTomlProto(const IWString& fname) {
+  const std::string string_fname(fname.data(), fname.length());
+
+  auto as_toml = toml::parse_file(string_fname);
+  if (! as_toml) {
+    std::cerr << "ReadTomlProto:parse_file failed " << string_fname << '\n';
+    return std::nullopt;
+  }
+
+  return TomlToProto<Proto>(std::move(as_toml));
+}
+
+template <typename Proto>
+std::optional<Proto>
+ParseFromToml(const std::string& toml_string) {
+  auto as_toml = toml::parse(toml_string);
+  if (! as_toml) {
+    std::cerr << "ParseFromToml:Cannot parse as TOML\n";
+    std::cerr << toml_string << '\n';
+    return std::nullopt;
+  }
+
+  return TomlToProto<Proto>(std::move(as_toml));
+}
+
+}
+
+#endif // FOUNDATIONAL_IWMISC_TOML_SUPPORT_H_

src/Foundational/iwmisc/toml_support_test.cc

@@ -0,0 +1,88 @@
+// Unit tests
+
+#include <optional>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "google/protobuf/text_format.h"
+
+#include "Foundational/iwmisc/toml_support.h"
+
+#include "Foundational/iwmisc/for_testing.pb.h"
+
+namespace {
+
+using testing::ElementsAre;
+using testing::Eq;
+
+using for_testing::TestMessage;
+
+TEST(Test, TestStrings) {
+  const std::string toml = R"(
+str1 = "hello"
+str2 = "world"
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_EQ(msg->str1(), "hello");
+  EXPECT_EQ(msg->str2(), "world");
+}
+
+
+TEST(Test, TestInt) {
+  const std::string toml = R"(
+i1 = -12
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_EQ(msg->i1(), -12);
+}
+
+TEST(Test, TestUInt) {
+  const std::string toml = R"(
+ui1 = 12
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_EQ(msg->ui1(), 12);
+}
+
+TEST(Test, TestFloat) {
+  const std::string toml = R"(
+x = 12.0
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_FLOAT_EQ(msg->x(), static_cast<float>(12.0));
+}
+
+TEST(Test, TestIntArray) {
+  const std::string toml = R"(
+int_array = [1,2,3,4,5]
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_THAT(msg->int_array(), ElementsAre(1,2,3,4,5));
+}
+
+TEST(Test, TestSubMessage) {
+  const std::string toml = R"(
+repeated_string = ["hello", "world"]
+[sub_message]
+i1 = 3
+str1 = "vr46"
+)";
+  std::optional<TestMessage> msg = iwmisc::ParseFromToml<TestMessage>(toml);
+  EXPECT_NE(msg, std::nullopt);
+
+  EXPECT_THAT(msg->repeated_string(), ElementsAre("hello", "world"));
+  EXPECT_THAT(msg->sub_message().i1(), Eq(3));
+  EXPECT_THAT(msg->sub_message().str1(), Eq("vr46"));
+}
+
+}  // namespace

src/MODULE.bazel

@@ -39,7 +39,5 @@ bazel_dep(name = "rules_pkg", version = "0.10.1")
 bazel_dep(name = "rules_proto", version = "6.0.2")
 bazel_dep(name = "rules_proto_grpc", version = "5.0.0")
 bazel_dep(name = "rules_ruby", version = "0.12.0")
-# Seem to be two toml handlers. Figure out which to use...
-# bazel_dep(name = "tomlplusplus", version = "3.4.0")
-# bazel_dep(name = "cpptoml", version = "0.1.1")
+bazel_dep(name = "tomlplusplus", version = "3.4.0")
 bazel_dep(name = "zlib", version = "1.3.1")