3 files changed, 65 insertions, 0 deletions
diff --git a/libs/nanopb/tests/regression/issue_256/SConscript b/libs/nanopb/tests/regression/issue_256/SConscript
new file mode 100644
index 00000000..b2c3e864
--- /dev/null
+++ b/libs/nanopb/tests/regression/issue_256/SConscript
@@ -0,0 +1,16 @@
+# Regression test for Issue 256: Proto3 mode skips submessages even when
+# later array fields have non-zero value
+
+Import('env')
+
+env.NanopbProto('submsg_array')
+
+p = env.Program(['submsg_array.c',
+                 'submsg_array.pb.c', 
+                 "$COMMON/pb_decode.o",
+                 "$COMMON/pb_encode.o",
+                 "$COMMON/pb_common.o"])
+
+env.RunTest(p)
+
+
diff --git a/libs/nanopb/tests/regression/issue_256/submsg_array.c b/libs/nanopb/tests/regression/issue_256/submsg_array.c
new file mode 100644
index 00000000..c63bd30a
--- /dev/null
+++ b/libs/nanopb/tests/regression/issue_256/submsg_array.c
@@ -0,0 +1,38 @@
+#include <unittests.h>
+#include <pb_encode.h>
+#include <pb_decode.h>
+#include "submsg_array.pb.h"
+
+int main()
+{
+    int status = 0;
+    
+    COMMENT("Test encoding for submessage with array");
+    {
+        uint8_t buffer[TestMessage_size] = {0};
+        pb_ostream_t ostream = pb_ostream_from_buffer(buffer, TestMessage_size);
+        TestMessage msg = TestMessage_init_zero;
+        
+        msg.submsg.rep_uint32_count = 3;
+        msg.submsg.rep_uint32[0] = 0;
+        msg.submsg.rep_uint32[1] = 1;
+        msg.submsg.rep_uint32[2] = 2;
+        
+        TEST(pb_encode(&ostream, TestMessage_fields, &msg));
+        TEST(ostream.bytes_written > 0);
+        
+        {
+            pb_istream_t istream = pb_istream_from_buffer(buffer, ostream.bytes_written);
+            TestMessage msg2 = TestMessage_init_zero;
+
+            TEST(pb_decode(&istream, TestMessage_fields, &msg2));
+            TEST(msg2.submsg.rep_uint32_count == 3);
+            TEST(msg2.submsg.rep_uint32[0] == 0);
+            TEST(msg2.submsg.rep_uint32[1] == 1);
+            TEST(msg2.submsg.rep_uint32[2] == 2);
+        }
+    }
+    
+    return status;
+}
+
diff --git a/libs/nanopb/tests/regression/issue_256/submsg_array.proto b/libs/nanopb/tests/regression/issue_256/submsg_array.proto
new file mode 100644
index 00000000..4964a05f
--- /dev/null
+++ b/libs/nanopb/tests/regression/issue_256/submsg_array.proto
@@ -0,0 +1,11 @@
+syntax = "proto3";
+import "nanopb.proto";
+
+message SubMessage {
+    repeated uint32 rep_uint32 = 1 [(nanopb).max_count = 3];
+}
+
+message TestMessage {
+    SubMessage submsg = 1;
+}
+