From 74ec4e071c2b9f2ca6add94fb2601feb9e7791ad Mon Sep 17 00:00:00 2001
From: Sam Eiderman <sameid@gmail.com>
Date: Tue, 27 Dec 2022 20:41:41 +0200
Subject: [PATCH] Support field extensions with use_allof_for_refs

---
 protoc-gen-openapiv2/internal/genopenapi/template.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/protoc-gen-openapiv2/internal/genopenapi/template.go b/protoc-gen-openapiv2/internal/genopenapi/template.go
index ce69c34bd67..85323279872 100644
--- a/protoc-gen-openapiv2/internal/genopenapi/template.go
+++ b/protoc-gen-openapiv2/internal/genopenapi/template.go
@@ -520,11 +520,12 @@ func renderMessageAsDefinition(msg *descriptor.Message, reg *descriptor.Registry
 				// Per the JSON Reference syntax: Any members other than "$ref" in a JSON Reference object SHALL be ignored.
 				// https://tools.ietf.org/html/draft-pbryan-zyp-json-ref-03#section-3
 				// However, use allOf to specify Title/Description/readOnly fields.
-				if fieldSchema.Title != "" || fieldSchema.Description != "" || fieldSchema.ReadOnly {
+				if fieldSchema.Title != "" || fieldSchema.Description != "" || fieldSchema.ReadOnly || len(fieldSchema.extensions) > 0 {
 					fieldSchema = openapiSchemaObject{
 						Title:       fieldSchema.Title,
 						Description: fieldSchema.Description,
 						ReadOnly:    fieldSchema.ReadOnly,
+						extensions:  fieldSchema.extensions,
 						AllOf:       []allOfEntry{{Ref: fieldSchema.Ref}},
 					}
 				} else {