Fix bug with decoding empty message types. Add test for the same.

Note: the bug only applies to empty message types. Empty messages
of non-empty message types are not affected.

Update issue 65
Status: FixedInGit

pb_decode.c

@@ -571,7 +571,7 @@ bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[
         } while (pb_field_next(&iter));
         
         /* Fixup if last field was also required. */
-        if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED)
+        if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.current->tag)
             req_field_count++;
         
         /* Check the whole bytes */

tests/alltypes.proto

@@ -6,6 +6,10 @@ message SubMessage {
     optional fixed32 substuff3 = 3 [default = 3];
 }
 
+message EmptyMessage {
+
+}
+
 enum MyEnum {
     Zero = 0;
     First = 1;
@@ -34,6 +38,7 @@ message AllTypes {
     required bytes      req_bytes   = 15 [(nanopb).max_size = 16];
     required SubMessage req_submsg  = 16;
     required MyEnum     req_enum    = 17;
+    required EmptyMessage req_emptymsg = 18;
     
     
     repeated int32      rep_int32   = 21 [(nanopb).max_count = 5];
@@ -56,6 +61,7 @@ message AllTypes {
     repeated bytes      rep_bytes   = 35 [(nanopb).max_size = 16, (nanopb).max_count = 5];
     repeated SubMessage rep_submsg  = 36 [(nanopb).max_count = 5];
     repeated MyEnum     rep_enum    = 37 [(nanopb).max_count = 5];
+    repeated EmptyMessage rep_emptymsg = 38 [(nanopb).max_count = 5];
     
     optional int32      opt_int32   = 41 [default = 4041];
     optional int64      opt_int64   = 42 [default = 4042];
@@ -77,6 +83,7 @@ message AllTypes {
     optional bytes      opt_bytes   = 55 [(nanopb).max_size = 16, default = "4055"];
     optional SubMessage opt_submsg  = 56;
     optional MyEnum     opt_enum    = 57 [default = Second];
+    optional EmptyMessage opt_emptymsg = 58;
 
     // Just to make sure that the size of the fields has been calculated
     // properly, i.e. otherwise a bug in last field might not be detected.

tests/test_decode3.c

@@ -76,6 +76,7 @@ bool check_alltypes(pb_istream_t *stream, int mode)
     TEST(alltypes.rep_submsg[4].substuff3 == 2016 && alltypes.rep_submsg[0].substuff3 == 3);
     
     TEST(alltypes.rep_enum_count == 5 && alltypes.rep_enum[4] == MyEnum_Truth && alltypes.rep_enum[0] == MyEnum_Zero);
+    TEST(alltypes.rep_emptymsg_count == 5);
     
     if (mode == 0)
     {
@@ -120,6 +121,7 @@ bool check_alltypes(pb_istream_t *stream, int mode)
         TEST(alltypes.opt_submsg.substuff3 == 3);
         TEST(alltypes.has_opt_enum     == false);
         TEST(alltypes.opt_enum == MyEnum_Second);
+        TEST(alltypes.has_opt_emptymsg == false);
     }
     else
     {
@@ -164,6 +166,7 @@ bool check_alltypes(pb_istream_t *stream, int mode)
         TEST(alltypes.opt_submsg.substuff3 == 3);
         TEST(alltypes.has_opt_enum      == true);
         TEST(alltypes.opt_enum == MyEnum_Truth);
+        TEST(alltypes.has_opt_emptymsg  == true);
     }
     
     TEST(alltypes.end == 1099);

tests/test_encode3.c

@@ -64,6 +64,7 @@ int main(int argc, char **argv)
     alltypes.rep_submsg[4].substuff3 = 2016;
     
     alltypes.rep_enum_count = 5; alltypes.rep_enum[4] = MyEnum_Truth;
+    alltypes.rep_emptymsg_count = 5;
     
     if (mode != 0)
     {
@@ -107,6 +108,7 @@ int main(int argc, char **argv)
         alltypes.opt_submsg.substuff2 = 3056;
         alltypes.has_opt_enum = true;
         alltypes.opt_enum = MyEnum_Truth;
+        alltypes.has_opt_emptymsg = true;
     }
     
     alltypes.end = 1099;