Dramatically accelerate chain_test, fix core asset burn bug

When generating blocks until a timestamp, we now generate one block
immediately, then skip blocks until the timestamp, and generate a
final block then.

Also, this exposed a bug in the witness budget handling which
caused the undesired burning of core asset. This bug is now fixed.

libraries/chain/db_maint.cpp

@@ -272,8 +272,7 @@ void database::process_budget()
       });
       modify(dpo, [&]( dynamic_global_property_object& _dpo )
       {
-         // Should this be +=?
+         _dpo.witness_budget += witness_budget;
-         _dpo.witness_budget = witness_budget;
          _dpo.last_budget_time = now;
       });
 
@@ -406,8 +405,10 @@ void database::perform_chain_maintenance(const signed_block& next_block, const g
          next_maintenance_time = time_point_sec() +
                (((next_block.timestamp.sec_since_epoch() / maintenance_interval) + 1) * maintenance_interval);
       else
-         next_maintenance_time += maintenance_interval;
+         // It's possible we have missed blocks for at least a maintenance interval.
-      assert( next_maintenance_time > next_block.timestamp );
+         // In this case, we'll need to bump the next maintenance time more than once.
+         do next_maintenance_time += maintenance_interval;
+         while( next_maintenance_time < head_block_time() );
    }
 
    modify(get_dynamic_global_properties(), [next_maintenance_time](dynamic_global_property_object& d) {

tests/common/database_fixture.cpp

@@ -274,8 +274,9 @@ void database_fixture::generate_blocks(fc::time_point_sec timestamp, bool miss_i
 {
    if( miss_intermediate_blocks )
    {
+      generate_block();
       auto slots_to_miss = db.get_slot_at_time(timestamp) - 1;
-      assert(slots_to_miss > 0);
+      if( slots_to_miss <= 0 ) return;
       generate_block(~0, generate_private_key("genesis"), slots_to_miss);
       return;
    }

tests/common/database_fixture.hpp

@@ -126,7 +126,7 @@ struct database_fixture {
     * @brief Generates blocks until the head block time matches or exceeds timestamp
     * @param timestamp target time to generate blocks until
     */
-   void generate_blocks(fc::time_point_sec timestamp, bool miss_intermediate_blocks = false);
+   void generate_blocks(fc::time_point_sec timestamp, bool miss_intermediate_blocks = true);
 
    account_create_operation make_account(
       const std::string& name = "nathan",

tests/tests/block_tests.cpp

@@ -568,7 +568,7 @@ BOOST_FIXTURE_TEST_CASE( short_order_expiration, database_fixture )
    BOOST_CHECK_EQUAL( get_balance(*nathan, *core), 49500 );
    auto id = short_itr->id;
 
-   generate_blocks(op.expiration);
+   generate_blocks(op.expiration, false);
    test = &get_asset("TEST");
    core = &asset_id_type()(db);
    nathan = &get_account("nathan");
@@ -611,7 +611,7 @@ BOOST_FIXTURE_TEST_CASE( limit_order_expiration, database_fixture )
    BOOST_CHECK_EQUAL( get_balance(*nathan, *core), 49500 );
    auto id = limit_itr->id;
 
-   generate_blocks(op.expiration);
+   generate_blocks(op.expiration, false);
    test = &get_asset("TEST");
    core = &asset_id_type()(db);
    nathan = &get_account("nathan");

tests/tests/operation_tests2.cpp

@@ -671,9 +671,12 @@ BOOST_AUTO_TEST_CASE( refund_worker_test )
    }
 
    // auto supply = asset_id_type()(db).dynamic_data(db).current_supply;
+   verify_asset_supplies();
    generate_blocks(db.get_dynamic_global_properties().next_maintenance_time);
+   verify_asset_supplies();
    BOOST_CHECK_EQUAL(worker_id_type()(db).worker.get<refund_worker_type>().total_burned.value, 1000);
    generate_blocks(db.get_dynamic_global_properties().next_maintenance_time);
+   verify_asset_supplies();
    BOOST_CHECK_EQUAL(worker_id_type()(db).worker.get<refund_worker_type>().total_burned.value, 2000);
    generate_blocks(db.get_dynamic_global_properties().next_maintenance_time);
    BOOST_CHECK(!db.get(worker_id_type()).is_active(db.head_block_time()));