test: add test for decoding PSBT with per-input preimage types

Author: theStack

test/functional/rpc_psbt.py

@@ -11,10 +11,23 @@
 from test_framework.descriptors import descsum_create
 from test_framework.key import ECKey, H_POINT
 from test_framework.messages import (
+    COutPoint,
+    CTransaction,
+    CTxIn,
+    CTxOut,
     MAX_BIP125_RBF_SEQUENCE,
     WITNESS_SCALE_FACTOR,
     ser_compact_size,
 )
+from test_framework.psbt import (
+    PSBT,
+    PSBTMap,
+    PSBT_GLOBAL_UNSIGNED_TX,
+    PSBT_IN_RIPEMD160,
+    PSBT_IN_SHA256,
+    PSBT_IN_HASH160,
+    PSBT_IN_HASH256,
+)
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_approx,
@@ -23,6 +36,7 @@
     assert_raises_rpc_error,
     find_output,
     find_vout_for_address,
+    random_bytes,
 )
 from test_framework.wallet_util import bytes_to_wif
 
@@ -775,5 +789,37 @@ def test_psbt_input_keys(psbt_input, keys):
             self.nodes[0].sendrawtransaction(rawtx)
             self.generate(self.nodes[0], 1)
 
+        self.log.info("Test decoding PSBT with per-input preimage types")
+        # note that the decodepsbt RPC doesn't check whether preimages and hashes match
+        hash_ripemd160, preimage_ripemd160 = random_bytes(20), random_bytes(50)
+        hash_sha256, preimage_sha256 = random_bytes(32), random_bytes(50)
+        hash_hash160, preimage_hash160 = random_bytes(20), random_bytes(50)
+        hash_hash256, preimage_hash256 = random_bytes(32), random_bytes(50)
+
+        tx = CTransaction()
+        tx.vin = [CTxIn(outpoint=COutPoint(hash=int('aa' * 32, 16), n=0), scriptSig=b""),
+                  CTxIn(outpoint=COutPoint(hash=int('bb' * 32, 16), n=0), scriptSig=b""),
+                  CTxIn(outpoint=COutPoint(hash=int('cc' * 32, 16), n=0), scriptSig=b""),
+                  CTxIn(outpoint=COutPoint(hash=int('dd' * 32, 16), n=0), scriptSig=b"")]
+        tx.vout = [CTxOut(nValue=0, scriptPubKey=b"")]
+        psbt = PSBT()
+        psbt.g = PSBTMap({PSBT_GLOBAL_UNSIGNED_TX: tx.serialize()})
+        psbt.i = [PSBTMap({bytes([PSBT_IN_RIPEMD160]) + hash_ripemd160: preimage_ripemd160}),
+                  PSBTMap({bytes([PSBT_IN_SHA256]) + hash_sha256: preimage_sha256}),
+                  PSBTMap({bytes([PSBT_IN_HASH160]) + hash_hash160: preimage_hash160}),
+                  PSBTMap({bytes([PSBT_IN_HASH256]) + hash_hash256: preimage_hash256})]
+        psbt.o = [PSBTMap()]
+        res_inputs = self.nodes[0].decodepsbt(psbt.to_base64())["inputs"]
+        assert_equal(len(res_inputs), 4)
+        preimage_keys = ["ripemd160_preimages", "sha256_preimages", "hash160_preimages", "hash256_preimages"]
+        expected_hashes = [hash_ripemd160, hash_sha256, hash_hash160, hash_hash256]
+        expected_preimages = [preimage_ripemd160, preimage_sha256, preimage_hash160, preimage_hash256]
+        for res_input, preimage_key, hash, preimage in zip(res_inputs, preimage_keys, expected_hashes, expected_preimages):
+            assert preimage_key in res_input
+            assert_equal(len(res_input[preimage_key]), 1)
+            assert hash.hex() in res_input[preimage_key]
+            assert_equal(res_input[preimage_key][hash.hex()], preimage.hex())
+
+
 if __name__ == '__main__':
     PSBTTest().main()