test: refactor: support sending funds with outpoint result

This commit introduces a helper `create_outpoints` to execute the
`send` RPC and immediately return the target address outpoints as UTXO
dictionary in the common format, making the tests more readable and
avoiding unnecessary duplication.

test/functional/wallet_basic.py

@@ -18,7 +18,6 @@ from test_framework.util import (
     assert_equal,
     assert_fee_amount,
     assert_raises_rpc_error,
-    find_vout_for_address,
 )
 from test_framework.wallet_util import test_address
 from test_framework.wallet import MiniWallet
@@ -471,10 +470,9 @@ class WalletTest(BitcoinTestFramework):
             # Import address and private key to check correct behavior of spendable unspents
             # 1. Send some coins to generate new UTXO
             address_to_import = self.nodes[2].getnewaddress()
-            txid = self.nodes[0].sendtoaddress(address_to_import, 1)
+            utxo = self.create_outpoints(self.nodes[0], outputs=[{address_to_import: 1}])[0]
             self.sync_mempools(self.nodes[0:3])
-            vout = find_vout_for_address(self.nodes[2], txid, address_to_import)
-            self.nodes[2].lockunspent(False, [{"txid": txid, "vout": vout}])
+            self.nodes[2].lockunspent(False, [utxo])
             self.generate(self.nodes[0], 1, sync_fun=lambda: self.sync_all(self.nodes[0:3]))
 
             self.log.info("Test sendtoaddress with fee_rate param (explicit fee rate in sat/vB)")