Add jvm walletTxBuilderDrainWallet test

jvm/src/test/kotlin/org/bitcoindevkit/JvmLibTest.kt

@@ -136,8 +136,7 @@ class JvmLibTest {
             assertNotNull(txid)
         } else {
             val depositAddress = wallet.getLastUnusedAddress()
-            println("Send more testnet coins to: $depositAddress")
-            fail()
+            fail("Send more testnet coins to: $depositAddress")
         }
     }
 
@@ -150,4 +149,27 @@ class JvmLibTest {
         txBuilder.build(wallet)
     }
 
+    @Test
+    fun walletTxBuilderDrainWallet() {
+        val descriptor =
+            "wpkh([8da6afbe/84'/1'/0'/0]tprv8hY7jbMbe17EH1cLw2feTyNDYvjcFYauLmbneBqVnDERBrV51LrxWjCYRZwWS5keYn3ijb7iHJuEzXQk7EzgPeKRBVNBgC4oFPDxGND5S3V/*)"
+        val wallet = Wallet(descriptor, null, Network.TESTNET, databaseConfig, blockchainConfig)
+        wallet.sync(LogProgress(), null)
+        val balance = wallet.getBalance()
+        if (balance > 2000u) {
+            println("balance $balance")
+            // send all coins back to https://bitcoinfaucet.uo1.net
+            val faucetAddress = "tb1ql7w62elx9ucw4pj5lgw4l028hmuw80sndtntxt"
+            val txBuilder = TxBuilder().drainWallet().drainTo(faucetAddress).feeRate(1.1f)
+            val psbt = txBuilder.build(wallet)
+            wallet.sign(psbt)
+            val txid = wallet.broadcast(psbt)
+            println("https://mempool.space/testnet/tx/$txid")
+            assertNotNull(txid)
+        } else {
+            val depositAddress = wallet.getLastUnusedAddress()
+            fail("Send more testnet coins to: $depositAddress")
+        }
+    }
+
 }