From 32a29ce37767ec75b50067838936f8c2efcf54e7 Mon Sep 17 00:00:00 2001
From: Dave Syer <david_syer@hotmail.com>
Date: Fri, 26 Sep 2025 08:23:18 +0000
Subject: [PATCH 1/2] [protobuf] Fix blockLit to allow trailing comma

Apparently the trailing comma is optional in blockLit, see
https://github.com/protocolbuffers/protobuf/blob/main/src/google/protobuf/descriptor.proto#L1026
for example. There are other examples in that file that use trailing commas
as list delimiters.

I think this change is probably also required by #4631 to be fully correct,
but it is somewhat independent of that issue.
---
 protobuf/protobuf2/Protobuf2.g4 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/protobuf/protobuf2/Protobuf2.g4 b/protobuf/protobuf2/Protobuf2.g4
index 437349b2d3..ce562e2715 100644
--- a/protobuf/protobuf2/Protobuf2.g4
+++ b/protobuf/protobuf2/Protobuf2.g4
@@ -266,7 +266,7 @@ constant
 
 // not specified in specification but used in tests
 blockLit
-    : LC (ident COLON constant)* RC
+    : LC (ident COLON constant (COMMA)?)* RC
     ;
 
 emptyStatement_

From b8405a9a87ab1a1264ba4237c22c12d2001aaaed Mon Sep 17 00:00:00 2001
From: Dave Syer <david_syer@hotmail.com>
Date: Fri, 26 Sep 2025 09:44:00 +0000
Subject: [PATCH 2/2] Add example with blockLits

---
 protobuf/protobuf2/examples/block.proto | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 protobuf/protobuf2/examples/block.proto

diff --git a/protobuf/protobuf2/examples/block.proto b/protobuf/protobuf2/examples/block.proto
new file mode 100644
index 0000000000..5db19068a2
--- /dev/null
+++ b/protobuf/protobuf2/examples/block.proto
@@ -0,0 +1,22 @@
+syntax = 'proto2';
+
+// Extracted from google/protobuf/descriptor.proto
+message FeatureSet {
+  enum FieldPresence {
+    FIELD_PRESENCE_UNKNOWN = 0;
+    EXPLICIT = 1;
+    IMPLICIT = 2;
+    LEGACY_REQUIRED = 3;
+  }
+  optional FieldPresence field_presence = 1 [
+    retention = RETENTION_RUNTIME,
+    targets = TARGET_TYPE_FIELD,
+    targets = TARGET_TYPE_FILE,
+    feature_support = {
+      edition_introduced: EDITION_2023,
+    },
+    edition_defaults = { edition: EDITION_LEGACY, value: "EXPLICIT" },
+    edition_defaults = { edition: EDITION_PROTO3, value: "IMPLICIT" },
+    edition_defaults = { edition: EDITION_2023, value: "EXPLICIT" }
+  ];
+}
\ No newline at end of file