avoid errors from minting sub-existential balance

Signed-off-by: Uncle Stinky <uncle.stinky@ghostchain.io>

pallets/slow-clap/src/tests.rs

@@ -265,7 +265,7 @@ fn should_increase_gatkeeper_amount_accordingly() {
         assert_ok!(do_clap_from(session_index, network_id, 1, false));
         assert_ok!(do_clap_from(session_index, network_id, 2, false));
 
-        assert_eq!(Networks::gatekeeper_amount(network_id), amount.saturating_div(2));
+        assert_eq!(Networks::gatekeeper_amount(network_id), amount);
         assert_eq!(Networks::bridged_imbalance().bridged_in, amount.saturating_div(2));
         assert_eq!(Networks::bridged_imbalance().bridged_out, 0);
     });
@@ -594,7 +594,7 @@ fn should_throw_error_on_commission_overflow() {
                 assert_ok!(SlowClap::slow_clap(RuntimeOrigin::none(), clap, signature));
             } else {
                 assert_err!(SlowClap::slow_clap(RuntimeOrigin::none(), clap, signature),
-                    Error::<Runtime>::CouldNotIncreaseGatekeeperAmount);
+                    Error::<Runtime>::CouldNotAccumulateIncomingImbalance);
             }
         }
 
@@ -617,19 +617,19 @@ fn should_nullify_commission_on_finalize() {
     let (_, _, amount) = get_mocked_metadata();
 
     new_test_ext().execute_with(|| {
-        let _ = prepare_evm_network(Some(network_id), Some(500_000_000));
+        let _ = prepare_evm_network(Some(network_id), Some(1_000_000_000));
         let session_index = advance_session_and_get_index();
 
         assert_eq!(Networks::accumulated_commission(), 0);
         assert_ok!(do_clap_from(session_index, network_id, 0, false));
         assert_ok!(do_clap_from(session_index, network_id, 1, false));
-        assert_eq!(Networks::accumulated_commission(), amount.saturating_div(2));
+        assert_eq!(Networks::accumulated_commission(), amount);
         assert_eq!(Networks::is_nullification_period(), false);
 
         assert_eq!(BridgedInflationCurve::<RewardCurve, Runtime>::era_payout(
                 total_staked,
-                (total_issuance + amount).into(),
-                0), (1260099399952u128, 208739900600048u128)); // precomputed values
+                total_issuance,
+                0), (420000000000000, 0)); // precomputed values
         assert_eq!(Networks::is_nullification_period(), true);
         Networks::on_finalize(System::block_number());
 
@@ -793,10 +793,40 @@ fn should_emit_event_on_each_clap_and_on_applause() {
     });
 }
 
+#[test]
+fn should_not_fail_on_sub_existential_balance() {
+    let (network_id, transaction_hash, unique_transaction_hash)
+        = generate_unique_hash(None, None, None, None);
+    let (_, receiver, amount) = get_mocked_metadata();
+
+    new_test_ext().execute_with(|| {
+        let _ = prepare_evm_network(Some(network_id), Some(1_000_000_000)); // 100%
+        let session_index = advance_session_and_get_index();
+        let received_claps_key = (session_index, transaction_hash, unique_transaction_hash);
+
+        assert_eq!(Networks::accumulated_commission(), 0);
+        assert_eq!(Networks::gatekeeper_amount(network_id), 0);
+        assert_eq!(Networks::bridged_imbalance().bridged_in, 0);
+        assert_eq!(Networks::bridged_imbalance().bridged_out, 0);
+        assert_eq!(Balances::balance(&receiver), 0);
+        assert_eq!(SlowClap::applauses_for_transaction(&received_claps_key), false);
+
+        assert_ok!(do_clap_from(session_index, network_id, 0, false));
+        assert_ok!(do_clap_from(session_index, network_id, 1, false));
+        assert_ok!(do_clap_from(session_index, network_id, 2, false));
+
+        assert_eq!(Networks::accumulated_commission(), amount);
+        assert_eq!(Networks::gatekeeper_amount(network_id), amount);
+        assert_eq!(Networks::bridged_imbalance().bridged_in, 0);
+        assert_eq!(Networks::bridged_imbalance().bridged_out, 0);
+        assert_eq!(Balances::balance(&receiver), 0);
+        assert_eq!(SlowClap::applauses_for_transaction(&received_claps_key), true);
+    });
+}
+
 // TODO: multiple logs will create multiple records
 // TODO: errors should be checked as much as possible
 // TODO: offences generated as expected
-// TODO: deal with below existential amount after commission
 
 fn advance_session_and_get_index() -> u32 {
     advance_session();