Add dedicated tests to lock down that overridable defaults never change.

editions/BUILD

@@ -10,6 +10,18 @@ bzl_library(
     visibility = ["//visibility:public"],
 )
 
+# Aggregate all the features owned by the Protobuf repo.
+compile_edition_defaults(
+    name = "protobuf_defaults",
+    testonly = True,
+    srcs = [
+        "//java/core:java_features_proto",
+        "//src/google/protobuf:cpp_features_proto",
+    ],
+    maximum_edition = "2023",
+    minimum_edition = "2023",
+)
+
 compile_edition_defaults(
     name = "test_defaults_2023",
     testonly = True,
@@ -75,18 +87,36 @@ cc_library(
     ],
 )
 
+cc_proto_library(
+    name = "cpp_features_cc_proto",
+    testonly = True,
+    deps = ["//src/google/protobuf:cpp_features_proto"],
+)
+
+cc_proto_library(
+    name = "java_features_cc_proto",
+    testonly = True,
+    deps = ["//java/core:java_features_proto"],
+)
+
 cc_test(
     name = "defaults_test",
     srcs = ["defaults_test.cc"],
     data = [
+        ":protobuf_defaults",
         ":test_defaults_2023",
         ":test_defaults_far_future",
         ":test_defaults_future",
     ],
     deps = [
+        ":cpp_features_cc_proto",
         ":defaults_test_embedded",
+        ":java_features_cc_proto",
+        "//:protobuf",
         "//src/google/protobuf",
         "//src/google/protobuf:port",
+        "//src/google/protobuf:protobuf_lite",
+        "//src/google/protobuf:test_textproto",
         "//src/google/protobuf:unittest_features_cc_proto",
         "//src/google/protobuf/stubs",
         "//src/google/protobuf/testing",

editions/defaults_test.cc

@@ -12,11 +12,17 @@
 #include "absl/strings/escaping.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"
+#include "google/protobuf/java_features.pb.h"
+#include "google/protobuf/cpp_features.pb.h"
 #include "editions/defaults_test_embedded.h"
 #include "editions/defaults_test_embedded_base64.h"
+#include "google/protobuf/extension_set.h"
+#include "google/protobuf/message.h"
+#include "google/protobuf/test_textproto.h"
 #include "google/protobuf/unittest_features.pb.h"
 #include "google/protobuf/stubs/status_macros.h"
 
+
 // Must be included last.
 #include "google/protobuf/port_def.inc"
 
@@ -182,6 +188,63 @@ TEST(DefaultsTest, EmbeddedBase64) {
             pb::VALUE3);
 }
 
+// Lock down that overridable defaults never change in released editions.  After
+// an edition has been released these tests should never need to be touched.
+class OverridableDefaultsTest : public ::testing::Test {
+ public:
+  OverridableDefaultsTest() = default;
+  static void SetUpTestSuite() {
+    google::protobuf::LinkExtensionReflection(pb::cpp);
+    google::protobuf::LinkExtensionReflection(pb::java);
+    DescriptorPool::generated_pool();
+  }
+};
+
+// TODO Enable these once they become fixed internally.
+TEST_F(OverridableDefaultsTest, Proto2) {
+  auto feature_defaults = ReadDefaults("protobuf_defaults");
+  ASSERT_OK(feature_defaults);
+  ASSERT_GE(feature_defaults->defaults().size(), 1);
+  const auto& defaults = feature_defaults->defaults(0);
+  ASSERT_EQ(defaults.edition(), EDITION_PROTO2);
+
+  EXPECT_THAT(defaults.overridable_features(), EqualsProto(R"pb([pb.cpp] {}
+                                                                [pb.java] {}
+              )pb"));
+}
+TEST_F(OverridableDefaultsTest, Proto3) {
+  auto feature_defaults = ReadDefaults("protobuf_defaults");
+  ASSERT_OK(feature_defaults);
+  ASSERT_GE(feature_defaults->defaults().size(), 2);
+  const auto& defaults = feature_defaults->defaults(1);
+  ASSERT_EQ(defaults.edition(), EDITION_PROTO3);
+
+  EXPECT_THAT(defaults.overridable_features(), EqualsProto(R"pb([pb.cpp] {}
+                                                                [pb.java] {}
+              )pb"));
+}
+
+// Lock down that 2023 overridable defaults never change.  Once Edition 2023 has
+// been released this test should never need to be touched.
+TEST_F(OverridableDefaultsTest, Edition2023) {
+  auto feature_defaults = ReadDefaults("protobuf_defaults");
+  ASSERT_OK(feature_defaults);
+  ASSERT_GE(feature_defaults->defaults().size(), 3);
+  const auto& defaults = feature_defaults->defaults(2);
+  ASSERT_EQ(defaults.edition(), EDITION_2023);
+
+  EXPECT_THAT(defaults.overridable_features(), EqualsProto(R"pb(
+                field_presence: EXPLICIT
+                enum_type: OPEN
+                repeated_field_encoding: PACKED
+                utf8_validation: VERIFY
+                message_encoding: LENGTH_PREFIXED
+                json_format: ALLOW
+                [pb.cpp] { legacy_closed_enum: false string_type: STRING }
+                [pb.java] { legacy_closed_enum: false utf8_validation: DEFAULT }
+              )pb"));
+}
+
 }  // namespace
 }  // namespace protobuf
 }  // namespace google

java/core/BUILD.bazel

@@ -187,6 +187,7 @@ proto_library(
     strip_import_prefix = "/java/core/src/main/resources",
     visibility = [
         "//:__pkg__",
+        "//editions:__pkg__",
         "//java/__subpackages__",
         "//pkg:__pkg__",
     ],