From 55ab8316c14569cadc578e15ffdea4f1bcbb0964 Mon Sep 17 00:00:00 2001
From: Thomas Van Lenten <thomasvl@google.com>
Date: Tue, 22 Aug 2023 08:27:05 -0700
Subject: [PATCH] [ObjC] Enable generation of .proto files using editions.

PiperOrigin-RevId: 559119403
---
 .../protobuf/compiler/objectivec/file.cc      | 32 +++++++++++--------
 .../protobuf/compiler/objectivec/generator.cc | 13 ++++++++
 .../protobuf/compiler/objectivec/generator.h  |  2 +-
 .../protobuf/compiler/objectivec/options.h    |  2 ++
 4 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/src/google/protobuf/compiler/objectivec/file.cc b/src/google/protobuf/compiler/objectivec/file.cc
index cb146a0aa4..28998cacff 100644
--- a/src/google/protobuf/compiler/objectivec/file.cc
+++ b/src/google/protobuf/compiler/objectivec/file.cc
@@ -734,19 +734,25 @@ void FileGenerator::EmitFileDescription(io::Printer* p) const {
 
   const std::string objc_prefix(FileClassPrefix(file_));
   std::string syntax;
-  switch (FileDescriptorLegacy(file_).syntax()) {
-    case FileDescriptorLegacy::Syntax::SYNTAX_UNKNOWN:
-      syntax = "GPBFileSyntaxUnknown";
-      break;
-    case FileDescriptorLegacy::Syntax::SYNTAX_PROTO2:
-      syntax = "GPBFileSyntaxProto2";
-      break;
-    case FileDescriptorLegacy::Syntax::SYNTAX_PROTO3:
-      syntax = "GPBFileSyntaxProto3";
-      break;
-    case FileDescriptorLegacy::Syntax::SYNTAX_EDITIONS:
-      syntax = "GPBFileSyntaxProtoEditions";
-      break;
+  if (generation_options_.experimental_strip_nonfunctional_codegen) {
+    // Doesn't matter for current sources, use Unknown as a marker for this
+    // mode.
+    syntax = "GPBFileSyntaxUnknown";
+  } else {
+    switch (FileDescriptorLegacy(file_).syntax()) {
+      case FileDescriptorLegacy::Syntax::SYNTAX_UNKNOWN:
+        syntax = "GPBFileSyntaxUnknown";
+        break;
+      case FileDescriptorLegacy::Syntax::SYNTAX_PROTO2:
+        syntax = "GPBFileSyntaxProto2";
+        break;
+      case FileDescriptorLegacy::Syntax::SYNTAX_PROTO3:
+        syntax = "GPBFileSyntaxProto3";
+        break;
+      case FileDescriptorLegacy::Syntax::SYNTAX_EDITIONS:
+        syntax = "GPBFileSyntaxProtoEditions";
+        break;
+    }
   }
 
   p->Emit({{"file_description_name", file_description_name_},
diff --git a/src/google/protobuf/compiler/objectivec/generator.cc b/src/google/protobuf/compiler/objectivec/generator.cc
index 4893d07f97..32d11f28f5 100644
--- a/src/google/protobuf/compiler/objectivec/generator.cc
+++ b/src/google/protobuf/compiler/objectivec/generator.cc
@@ -302,6 +302,16 @@ bool ObjectiveCGenerator::GenerateAll(
             options[i].second);
         return false;
       }
+    } else if (options[i].first == "experimental_strip_nonfunctional_codegen") {
+      if (!StringToBool(
+              options[i].second,
+              &generation_options.experimental_strip_nonfunctional_codegen)) {
+        *error = absl::StrCat(
+            "error: Unknown value for "
+            "experimental_strip_nonfunctional_codegen: ",
+            options[i].second);
+        return false;
+      }
     } else {
       *error =
           absl::StrCat("error: Unknown generator option: ", options[i].first);
@@ -314,6 +324,9 @@ bool ObjectiveCGenerator::GenerateAll(
   if (generation_options.experimental_multi_source_generation) {
     generation_options.headers_use_forward_declarations = false;
   }
+  if (generation_options.experimental_strip_nonfunctional_codegen) {
+    generation_options.generate_minimal_imports = true;
+  }
 
   // -----------------------------------------------------------------
 
diff --git a/src/google/protobuf/compiler/objectivec/generator.h b/src/google/protobuf/compiler/objectivec/generator.h
index 3219540959..0498a57cac 100644
--- a/src/google/protobuf/compiler/objectivec/generator.h
+++ b/src/google/protobuf/compiler/objectivec/generator.h
@@ -69,7 +69,7 @@ class PROTOC_EXPORT ObjectiveCGenerator : public CodeGenerator {
                    std::string* error) const override;
 
   uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
+    return (FEATURE_PROTO3_OPTIONAL | FEATURE_SUPPORTS_EDITIONS);
   }
 };
 
diff --git a/src/google/protobuf/compiler/objectivec/options.h b/src/google/protobuf/compiler/objectivec/options.h
index af9e3a5a4b..b852ca09c8 100644
--- a/src/google/protobuf/compiler/objectivec/options.h
+++ b/src/google/protobuf/compiler/objectivec/options.h
@@ -52,6 +52,8 @@ struct GenerationOptions {
   // TODO(thomasvl): Eventually flip this default to true.
   bool generate_minimal_imports = false;
   bool experimental_multi_source_generation = false;
+  // This is used by some of the protobuf infrastructure.
+  bool experimental_strip_nonfunctional_codegen = false;
 };
 
 }  // namespace objectivec