add unit test for IsBlockConfirmed

zetaclient/chains/base/observer.go

@@ -229,9 +229,11 @@ func (ob *Observer) WithLastBlock(lastBlock uint64) *Observer {
 }
 
 // IsBlockConfirmed checks if the given block number is confirmed.
+//
+// Note: block 100 is confirmed if the last block is 100 and confirmation count is 1.
 func (ob *Observer) IsBlockConfirmed(blockNumber uint64) bool {
 	lastBlock := ob.LastBlock()
-	confBlock := blockNumber + ob.chainParams.ConfirmationCount
+	confBlock := blockNumber + ob.chainParams.ConfirmationCount - 1
 	return lastBlock >= confBlock
 }
 

zetaclient/chains/base/observer_test.go

@@ -27,12 +27,16 @@ import (
 const (
 	// defaultAlertLatency is the default alert latency (in seconds) for unit tests
 	defaultAlertLatency = 60
+
+	// defaultConfirmationCount is the default confirmation count for unit tests
+	defaultConfirmationCount = 2
 )
 
 // createObserver creates a new observer for testing
 func createObserver(t *testing.T, chain chains.Chain, alertLatency int64) *base.Observer {
 	// constructor parameters
 	chainParams := *sample.ChainParams(chain.ChainId)
+	chainParams.ConfirmationCount = defaultConfirmationCount
 	zetacoreClient := mocks.NewZetacoreClient(t)
 	tss := mocks.NewTSSMainnet()
 
@@ -267,6 +271,51 @@ func TestObserverGetterAndSetter(t *testing.T) {
 	})
 }
 
+func TestIsBlockConfirmed(t *testing.T) {
+	tests := []struct {
+		name      string
+		chain     chains.Chain
+		block     uint64
+		lastBlock uint64
+		confirmed bool
+	}{
+		{
+			name:      "should confirm block 100 when confirmation arrives 2",
+			chain:     chains.BitcoinMainnet,
+			block:     100,
+			lastBlock: 101, // got 2 confirmations
+			confirmed: true,
+		},
+		{
+			name:      "should not confirm block 100 when confirmation < 2",
+			chain:     chains.BitcoinMainnet,
+			block:     100,
+			lastBlock: 100, // got 1 confirmation, need one more
+			confirmed: false,
+		},
+		{
+			name:      "should confirm block 100 when confirmation arrives 2",
+			chain:     chains.Ethereum,
+			block:     100,
+			lastBlock: 99, // last block lagging behind, need to wait
+			confirmed: false,
+		},
+	}
+
+	// run tests
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// create observer
+			ob := createObserver(t, tt.chain, defaultAlertLatency)
+			ob = ob.WithLastBlock(tt.lastBlock)
+
+			// check if block is confirmed
+			confirmed := ob.IsBlockConfirmed(tt.block)
+			require.Equal(t, tt.confirmed, confirmed)
+		})
+	}
+}
+
 func TestOutboundID(t *testing.T) {
 	tests := []struct {
 		name  string

zetaclient/chains/bitcoin/observer/inbound.go

@@ -290,6 +290,11 @@ func (ob *Observer) CheckReceiptForBtcTxHash(ctx context.Context, txHash string,
 		return "", err
 	}
 
+	// check confirmation
+	if !ob.IsBlockConfirmed(uint64(blockVb.Height)) {
+		return "", fmt.Errorf("block %d is not confirmed yet", blockVb.Height)
+	}
+
 	// calculate depositor fee
 	depositorFee, err := bitcoin.CalcDepositorFee(ob.btcClient, tx, ob.netParams)
 	if err != nil {