Started moving Kotlin DSL generator to its own directory.

PiperOrigin-RevId: 663760495

pkg/BUILD.bazel

@@ -198,7 +198,7 @@ cc_dist_library(
         "//src/google/protobuf/compiler/cpp",
         "//src/google/protobuf/compiler/csharp",
         "//src/google/protobuf/compiler/java",
-        "//src/google/protobuf/compiler/java:kotlin",
+        "//src/google/protobuf/compiler/kotlin",
         "//src/google/protobuf/compiler/objectivec",
         "//src/google/protobuf/compiler/php",
         "//src/google/protobuf/compiler/python",

src/google/protobuf/compiler/BUILD.bazel

@@ -195,7 +195,7 @@ cc_library(
         "//src/google/protobuf/compiler/cpp",
         "//src/google/protobuf/compiler/csharp",
         "//src/google/protobuf/compiler/java",
-        "//src/google/protobuf/compiler/java:kotlin",
+        "//src/google/protobuf/compiler/kotlin",
         "//src/google/protobuf/compiler/objectivec",
         "//src/google/protobuf/compiler/php",
         "//src/google/protobuf/compiler/python",

src/google/protobuf/compiler/java/BUILD.bazel

@@ -45,6 +45,7 @@ cc_library(
     visibility = [
         "//pkg:__pkg__",
         "//src/google/protobuf/compiler/java:__subpackages__",
+        "//src/google/protobuf/compiler/kotlin:__subpackages__",
     ],
     deps = [
         "//src/google/protobuf",
@@ -116,6 +117,7 @@ cc_library(
     visibility = [
         "//pkg:__pkg__",
         "//src/google/protobuf/compiler:__pkg__",
+        "//src/google/protobuf/compiler/kotlin:__subpackages__",
     ],
     deps = [
         ":generator_common",
@@ -182,25 +184,6 @@ cc_library(
     ],
 )
 
-cc_library(
-    name = "kotlin",
-    srcs = ["kotlin_generator.cc"],
-    hdrs = ["kotlin_generator.h"],
-    strip_include_prefix = "/src",
-    visibility = [
-        "//pkg:__pkg__",
-        "//src/google/protobuf/compiler:__pkg__",
-    ],
-    deps = [
-        ":helpers",
-        ":java",
-        "//src/google/protobuf",
-        "//src/google/protobuf:port",
-        "//src/google/protobuf/compiler:code_generator",
-        "@com_google_absl//absl/strings",
-    ],
-)
-
 cc_test(
     name = "doc_comment_unittest",
     srcs = ["doc_comment_unittest.cc"],

src/google/protobuf/compiler/kotlin/BUILD.bazel

@@ -0,0 +1,19 @@
+cc_library(
+    name = "kotlin",
+    srcs = ["generator.cc"],
+    hdrs = ["generator.h"],
+    strip_include_prefix = "/src",
+    visibility = [
+        "//pkg:__pkg__",
+        "//src/google/protobuf/compiler:__pkg__",
+    ],
+    deps = [
+        "//src/google/protobuf",
+        "//src/google/protobuf:port",
+        "//src/google/protobuf/compiler:code_generator",
+        "//src/google/protobuf/compiler/java",
+        "//src/google/protobuf/compiler/java:helpers",
+        "//src/google/protobuf/io:printer",
+        "@com_google_absl//absl/strings",
+    ],
+)

src/google/protobuf/compiler/kotlin/README.md

@@ -0,0 +1,16 @@
+
+# Kotlin DSL Generator
+
+This code generator implements the Kotlin DSL. The Kotlin DSL sits on top of
+another proto implementation (written in Java or Kotlin) and adds convenient
+support for building proto messages using DSL syntax, as documented in
+[Kotlin Generated Code Guide](https://protobuf.dev/reference/kotlin/kotlin-generated/).
+
+This code generator is invoked by passing `--kotlin_out` to `protoc`.
+
+When using Kotlin on the JVM, you will also need to pass `--java_out` to
+generate the Java code that implements the generated classes themselves.
+
+When using Kotlin on other platforms (eg. Kotlin Native), there is currently no
+support for generating message classes, so it is not possible to use the Kotlin
+DSL at this time.

src/google/protobuf/compiler/kotlin/generator.cc

@@ -5,14 +5,20 @@
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 
-#include "google/protobuf/compiler/java/kotlin_generator.h"
+#include "google/protobuf/compiler/kotlin/generator.h"
+
+#include <cstdint>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
 
 #include "absl/strings/str_cat.h"
 #include "google/protobuf/compiler/code_generator.h"
 #include "google/protobuf/compiler/java/file.h"
-#include "google/protobuf/compiler/java/generator.h"
 #include "google/protobuf/compiler/java/helpers.h"
 #include "google/protobuf/compiler/java/options.h"
+#include "google/protobuf/io/printer.h"
 
 namespace google {
 namespace protobuf {

src/google/protobuf/compiler/kotlin/generator.h

@@ -7,10 +7,12 @@
 
 // Generates Kotlin code for a given .proto file.
 
-#ifndef GOOGLE_PROTOBUF_COMPILER_JAVA_KOTLIN_GENERATOR_H__
-#define GOOGLE_PROTOBUF_COMPILER_JAVA_KOTLIN_GENERATOR_H__
+#ifndef GOOGLE_PROTOBUF_COMPILER_KOTLIN_GENERATOR_H__
+#define GOOGLE_PROTOBUF_COMPILER_KOTLIN_GENERATOR_H__
 
+#include <cstdint>
 #include <string>
+#include <vector>
 
 #include "google/protobuf/compiler/java/java_features.pb.h"
 #include "google/protobuf/compiler/code_generator.h"
@@ -58,4 +60,4 @@ class PROTOC_EXPORT KotlinGenerator : public CodeGenerator {
 
 #include "google/protobuf/port_undef.inc"
 
-#endif  // GOOGLE_PROTOBUF_COMPILER_JAVA_KOTLIN_GENERATOR_H__
+#endif  // GOOGLE_PROTOBUF_COMPILER_KOTLIN_GENERATOR_H__

src/google/protobuf/compiler/main.cc

@@ -10,7 +10,7 @@
 #include "google/protobuf/compiler/cpp/generator.h"
 #include "google/protobuf/compiler/csharp/csharp_generator.h"
 #include "google/protobuf/compiler/java/generator.h"
-#include "google/protobuf/compiler/java/kotlin_generator.h"
+#include "google/protobuf/compiler/kotlin/generator.h"
 #include "google/protobuf/compiler/objectivec/generator.h"
 #include "google/protobuf/compiler/php/php_generator.h"
 #include "google/protobuf/compiler/python/generator.h"