Fix broken tests #675

libraries/chain/block_log.cpp

@@ -201,7 +201,7 @@ namespace steemit { namespace chain {
    {
       optional< signed_block > b;
       uint64_t pos = get_block_pos( block_num );
-      if( !pos )
+      if( ~pos )
          b = read_block( pos ).first;
       return b;
    }

libraries/chain/database.cpp

@@ -277,7 +277,7 @@ optional<signed_block> database::fetch_block_by_number( uint32_t block_num )cons
    }
    else
    {
-      b = _block_log.read_block_by_num( stats->block_num() );
+      b = _block_log.read_block_by_num( block_num );
    }
 
    return b;

tests/tests/block_tests.cpp

@@ -74,7 +74,9 @@ BOOST_AUTO_TEST_CASE( generate_empty_blocks )
             uint32_t cutoff_height = db.get_dynamic_global_properties().last_irreversible_block_num;
             if( cutoff_height >= 200 )
             {
-               cutoff_block = *(db.fetch_block_by_number( cutoff_height ));
+               auto block = db.fetch_block_by_number( cutoff_height );
+               BOOST_REQUIRE( block.valid() );
+               cutoff_block = *block;
                break;
             }
          }

tests/tests/operation_time_tests.cpp

@@ -2558,7 +2558,7 @@ BOOST_AUTO_TEST_CASE( sbd_stability )
          auto& gpo = db.get_dynamic_global_properties();
          BOOST_REQUIRE( gpo.sbd_print_rate >= last_print_rate );
          last_print_rate = gpo.sbd_print_rate;
-         db_plugin->debug_generate_blocks( debug_key, 1, ~0 );
+         db_plugin->debug_generate_blocks( debug_key, 1, database::skip_witness_signature );
          validate_database();
       }