BIP352: add taproot key-path spend with annex vector

Add a BIP-352 test vector where a taproot input is spent via the key path with an annex (2-item witness). The annex must be stripped before deciding between key-path and script-path spends, so the input is still eligible and all expected values match the plain key-path case.

The annex is 0x50 followed by the BIP341 NUMS point H, so an implementation that fails to strip it reads it as a control block with the NUMS internal key and wrongly skips the input.

bip-0352/send_and_receive_test_vectors.json

@@ -5725,5 +5725,115 @@
                 }
             }
         ]
+    },
+    {
+        "comment": "Single recipient: taproot key-path spend with annex",
+        "sending": [
+            {
+                "given": {
+                    "vin": [
+                        {
+                            "txid": "f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16",
+                            "vout": 0,
+                            "scriptSig": "",
+                            "txinwitness": "0240c459b671370d12cfb5acee76da7e3ba7cc29b0b4653e3af8388591082660137d087fdc8e89a612cd5d15be0febe61fc7cdcf3161a26e599a4514aa5c3e86f47b215050929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0",
+                            "prevout": {
+                                "scriptPubKey": {
+                                    "hex": "51205a1e61f898173040e20616d43e9f496fba90338a39faa1ed98fcbaeee4dd9be5"
+                                }
+                            },
+                            "private_key": "eadc78165ff1f8ea94ad7cfdc54990738a4c53f6e0507b42154201b8e5dff3b1"
+                        },
+                        {
+                            "txid": "a1075db55d416d3ca199f55b6084e2115b9345e16c5cf302fc80e9d5fbf5d48d",
+                            "vout": 0,
+                            "scriptSig": "",
+                            "txinwitness": "0140bd1e708f92dbeaf24a6b8dd22e59c6274355424d62baea976b449e220fd75b13578e262ab11b7aa58e037f0c6b0519b66803b7d9decaa1906dedebfb531c56c1",
+                            "prevout": {
+                                "scriptPubKey": {
+                                    "hex": "5120782eeb913431ca6e9b8c2fd80a5f72ed2024ef72a3c6fb10263c379937323338"
+                                }
+                            },
+                            "private_key": "fc8716a97a48ba9a05a98ae47b5cd201a25a7fd5d8b73c203c5f7b6b6b3b6ad7"
+                        }
+                    ],
+                    "recipients": [
+                        {
+                            "address": "sp1qqgste7k9hx0qftg6qmwlkqtwuy6cycyavzmzj85c6qdfhjdpdjtdgqjuexzk6murw56suy3e0rd2cgqvycxttddwsvgxe2usfpxumr70xc9pkqwv",
+                            "scan_pub_key": "0220bcfac5b99e04ad1a06ddfb016ee13582609d60b6291e98d01a9bc9a16c96d4",
+                            "spend_pub_key": "025cc9856d6f8375350e123978daac200c260cb5b5ae83106cab90484dcd8fcf36"
+                        }
+                    ]
+                },
+                "expected": {
+                    "outputs": [
+                        [
+                            "de88bea8e7ffc9ce1af30d1132f910323c505185aec8eae361670421e749a1fb"
+                        ]
+                    ],
+                    "shared_secrets": [
+                        "02de9719785c6d09f71571dadf44bca59edba2af3e689c65cbc3bb5a4a387732ef"
+                    ],
+                    "input_private_key_sum": "e7638ebfda3ab3849a5707e240a6627671f7f6e609bf172691cf1e9780e51d47",
+                    "input_pub_keys": [
+                        "025a1e61f898173040e20616d43e9f496fba90338a39faa1ed98fcbaeee4dd9be5",
+                        "02782eeb913431ca6e9b8c2fd80a5f72ed2024ef72a3c6fb10263c379937323338"
+                    ]
+                }
+            }
+        ],
+        "receiving": [
+            {
+                "given": {
+                    "vin": [
+                        {
+                            "txid": "f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16",
+                            "vout": 0,
+                            "scriptSig": "",
+                            "txinwitness": "0240c459b671370d12cfb5acee76da7e3ba7cc29b0b4653e3af8388591082660137d087fdc8e89a612cd5d15be0febe61fc7cdcf3161a26e599a4514aa5c3e86f47b215050929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0",
+                            "prevout": {
+                                "scriptPubKey": {
+                                    "hex": "51205a1e61f898173040e20616d43e9f496fba90338a39faa1ed98fcbaeee4dd9be5"
+                                }
+                            }
+                        },
+                        {
+                            "txid": "a1075db55d416d3ca199f55b6084e2115b9345e16c5cf302fc80e9d5fbf5d48d",
+                            "vout": 0,
+                            "scriptSig": "",
+                            "txinwitness": "0140bd1e708f92dbeaf24a6b8dd22e59c6274355424d62baea976b449e220fd75b13578e262ab11b7aa58e037f0c6b0519b66803b7d9decaa1906dedebfb531c56c1",
+                            "prevout": {
+                                "scriptPubKey": {
+                                    "hex": "5120782eeb913431ca6e9b8c2fd80a5f72ed2024ef72a3c6fb10263c379937323338"
+                                }
+                            }
+                        }
+                    ],
+                    "outputs": [
+                        "de88bea8e7ffc9ce1af30d1132f910323c505185aec8eae361670421e749a1fb"
+                    ],
+                    "key_material": {
+                        "spend_priv_key": "9d6ad855ce3417ef84e836892e5a56392bfba05fa5d97ccea30e266f540e08b3",
+                        "scan_priv_key": "0f694e068028a717f8af6b9411f9a133dd3565258714cc226594b34db90c1f2c"
+                    },
+                    "labels": []
+                },
+                "expected": {
+                    "addresses": [
+                        "sp1qqgste7k9hx0qftg6qmwlkqtwuy6cycyavzmzj85c6qdfhjdpdjtdgqjuexzk6murw56suy3e0rd2cgqvycxttddwsvgxe2usfpxumr70xc9pkqwv"
+                    ],
+                    "outputs": [
+                        {
+                            "priv_key_tweak": "3fb9ce5ce1746ced103c8ed254e81f6690764637ddbc876ec1f9b3ddab776b03",
+                            "pub_key": "de88bea8e7ffc9ce1af30d1132f910323c505185aec8eae361670421e749a1fb",
+                            "signature": "c5acd25a8f021a4192f93bc34403fd8b76484613466336fb259c72d04c169824f2690ca34e96cee86b69f376c8377003268fda56feeb1b873e5783d7e19bcca5"
+                        }
+                    ],
+                    "tweak": "02dc59cc8e8873b65c1dd5c416d4fbeb647372c329bd84a70c05b310e222e2c183",
+                    "shared_secret": "02de9719785c6d09f71571dadf44bca59edba2af3e689c65cbc3bb5a4a387732ef",
+                    "input_pub_key_sum": "038180a2125f9d6dd116e1a6139be4d72fd5057dab6aaabaa5654817c11baeb3ba"
+                }
+            }
+        ]
     }
 ]