From fe83b68ac68f221a8a7cf105e541b6d6d682ad80 Mon Sep 17 00:00:00 2001
From: David Cowan <37003198+dacowan@users.noreply.github.com>
Date: Mon, 20 May 2019 14:01:44 -0700
Subject: [PATCH] Added a CPP UnPackSizePrefixed<struct_name> generated helper
 function (#5350)

* Added a cpp  UnPackSizePrefixed<struct_name> generated helper function

Missing helper function added to the cpp API generator for unpacking size prefixed structures

* Added generated test files
---
 samples/monster_generated.h                 | 6 ++++++
 src/idl_gen_cpp.cpp                         | 8 ++++++++
 tests/monster_extra_generated.h             | 6 ++++++
 tests/monster_test_generated.h              | 6 ++++++
 tests/union_vector/union_vector_generated.h | 6 ++++++
 5 files changed, 32 insertions(+)

diff --git a/samples/monster_generated.h b/samples/monster_generated.h
index 70c41baee..fd867f24d 100644
--- a/samples/monster_generated.h
+++ b/samples/monster_generated.h
@@ -865,6 +865,12 @@ inline flatbuffers::unique_ptr<MonsterT> UnPackMonster(
   return flatbuffers::unique_ptr<MonsterT>(GetMonster(buf)->UnPack(res));
 }
 
+inline flatbuffers::unique_ptr<MonsterT> UnPackSizePrefixedMonster(
+    const void *buf,
+    const flatbuffers::resolver_function_t *res = nullptr) {
+  return flatbuffers::unique_ptr<MonsterT>(GetSizePrefixedMonster(buf)->UnPack(res));
+}
+
 }  // namespace Sample
 }  // namespace MyGame
 
diff --git a/src/idl_gen_cpp.cpp b/src/idl_gen_cpp.cpp
index cfd25267a..33d7c14ad 100644
--- a/src/idl_gen_cpp.cpp
+++ b/src/idl_gen_cpp.cpp
@@ -474,6 +474,14 @@ class CppGenerator : public BaseGenerator {
         code_ += "(Get{{STRUCT_NAME}}(buf)->UnPack(res));";
         code_ += "}";
         code_ += "";
+
+        code_ += "inline {{UNPACK_RETURN}} UnPackSizePrefixed{{STRUCT_NAME}}(";
+        code_ += "    const void *buf,";
+        code_ += "    const flatbuffers::resolver_function_t *res = nullptr) {";
+        code_ += "  return {{UNPACK_TYPE}}\\";
+        code_ += "(GetSizePrefixed{{STRUCT_NAME}}(buf)->UnPack(res));";
+        code_ += "}";
+        code_ += "";
       }
     }
 
diff --git a/tests/monster_extra_generated.h b/tests/monster_extra_generated.h
index 87e6d4281..6ad3ca851 100644
--- a/tests/monster_extra_generated.h
+++ b/tests/monster_extra_generated.h
@@ -349,6 +349,12 @@ inline std::unique_ptr<MonsterExtraT> UnPackMonsterExtra(
   return std::unique_ptr<MonsterExtraT>(GetMonsterExtra(buf)->UnPack(res));
 }
 
+inline std::unique_ptr<MonsterExtraT> UnPackSizePrefixedMonsterExtra(
+    const void *buf,
+    const flatbuffers::resolver_function_t *res = nullptr) {
+  return std::unique_ptr<MonsterExtraT>(GetSizePrefixedMonsterExtra(buf)->UnPack(res));
+}
+
 }  // namespace MyGame
 
 #endif  // FLATBUFFERS_GENERATED_MONSTEREXTRA_MYGAME_H_
diff --git a/tests/monster_test_generated.h b/tests/monster_test_generated.h
index 693271b24..508a87ef2 100644
--- a/tests/monster_test_generated.h
+++ b/tests/monster_test_generated.h
@@ -3483,6 +3483,12 @@ inline flatbuffers::unique_ptr<MonsterT> UnPackMonster(
   return flatbuffers::unique_ptr<MonsterT>(GetMonster(buf)->UnPack(res));
 }
 
+inline flatbuffers::unique_ptr<MonsterT> UnPackSizePrefixedMonster(
+    const void *buf,
+    const flatbuffers::resolver_function_t *res = nullptr) {
+  return flatbuffers::unique_ptr<MonsterT>(GetSizePrefixedMonster(buf)->UnPack(res));
+}
+
 }  // namespace Example
 }  // namespace MyGame
 
diff --git a/tests/union_vector/union_vector_generated.h b/tests/union_vector/union_vector_generated.h
index 60c80b01e..150c8f455 100644
--- a/tests/union_vector/union_vector_generated.h
+++ b/tests/union_vector/union_vector_generated.h
@@ -850,4 +850,10 @@ inline flatbuffers::unique_ptr<MovieT> UnPackMovie(
   return flatbuffers::unique_ptr<MovieT>(GetMovie(buf)->UnPack(res));
 }
 
+inline flatbuffers::unique_ptr<MovieT> UnPackSizePrefixedMovie(
+    const void *buf,
+    const flatbuffers::resolver_function_t *res = nullptr) {
+  return flatbuffers::unique_ptr<MovieT>(GetSizePrefixedMovie(buf)->UnPack(res));
+}
+
 #endif  // FLATBUFFERS_GENERATED_UNIONVECTOR_H_