feat!: adding MinimumStake parameter

execution/executor/bond.go

@@ -70,6 +70,9 @@ func (e *BondExecutor) Execute(trx *tx.Tx, sb sandbox.Sandbox) error {
 	if receiverVal.Stake()+pld.Stake > sb.Params().MaximumStake {
 		return errors.Errorf(errors.ErrInvalidTx,
 			"validator's stake can't be more than %v", sb.Params().MaximumStake)
+	} else if pld.Stake < sb.Params().MinimumStake {
+		return errors.Errorf(errors.ErrInvalidTx,
+			"validator's stake can't be less than %v", sb.Params().MinimumStake)
 	}
 
 	senderAcc.IncSequence()

execution/executor/bond_test.go

@@ -88,6 +88,14 @@ func TestExecuteBondTx(t *testing.T) {
 		assert.Error(t, exe.Execute(trx, td.sandbox), "Execute again, should fail")
 	})
 
+	t.Run("Should fail, amount less than MinimumStake", func(t *testing.T) {
+		trx := tx.NewBondTx(td.stamp500000, senderAcc.Sequence()+1, senderAddr,
+			receiverAddr, pub, 1000, fee, "less than MinimumStake")
+
+		err := exe.Execute(trx, td.sandbox)
+		assert.Equal(t, errors.Code(err), errors.ErrInvalidTx)
+	})
+
 	t.Run("Should fail, public key should not set for existing validators", func(t *testing.T) {
 		trx := tx.NewBondTx(td.stamp500000, senderAcc.Sequence()+2, senderAddr,
 			receiverAddr, pub, amt, fee, "with public key")

types/param/param.go

@@ -14,6 +14,7 @@ type Params struct {
 	FeeFraction               float64 `cbor:"9,keyasint"`
 	MinimumFee                int64   `cbor:"10,keyasint"`
 	MaximumFee                int64   `cbor:"11,keyasint"`
+	MinimumStake              int64   `cobr:"12,keyasint"`
 	MaximumStake              int64   `cbor:"12,keyasint"`
 }
 
@@ -30,6 +31,7 @@ func DefaultParams() Params {
 		FeeFraction:               0.0001,
 		MinimumFee:                1000,
 		MaximumFee:                1000000,
+		MinimumStake:              1000000000,
 		MaximumStake:              1000000000000,
 	}
 }