prove every code assumption with real transaction data

- Classic send (ID 0, 4-byte encoding) via OP_RETURN: block 489,000
  tx 6335eefb... (pre-short_tx_type_id, sends TRIGGERS)
- OLGA already proves 4-byte encoding via multisig (ID 30, block ~310K)
- Rune early exit (byte > 0x4e): tx 1af2a846... correctly rejected
- Short OP_RETURN early exit (< 22 hex): tx 28baf937... correctly rejected
- P2TR "ord" inscription envelope: constructed from official Counterparty
  composer unit test (composertaproot_test.py) -- FAKE, clearly marked.
  Zero mainnet/testnet txs exist (inscription param defaults to false,
  confirmed by Counterparty team in GitHub issue #3179).

19 Counterparty tests covering all 3 encodings, both type ID formats,
and early exit paths.

Author: hans-crypto

src/counterparty/counterparty-parser.service.spec.ts

@@ -215,5 +215,88 @@ describe('CounterpartyParserService', () => {
       // CBOR-encoded fairminter payload (97 bytes, first byte was the type ID)
       expect(result.getMessageData().length).toBe(97);
     });
+
+    // !! FAKE TRANSACTION -- NOT FROM MAINNET OR ANY TESTNET !!
+    //
+    // The "ord" inscription envelope (OP_FALSE OP_IF "ord" [7] "xcp" ... OP_ENDIF)
+    // is used when composing with inscription=true (opt-in, defaults to false).
+    // As of March 2026, zero transactions on mainnet, testnet3, or testnet4 use
+    // this format. The Counterparty team confirmed inscription defaults to false
+    // (GitHub issue #3179). No public testnet API is available to search.
+    //
+    // The envelope script below is constructed from the official Counterparty
+    // composer unit test: counterparty-core/test/units/api/composertaproot_test.py
+    // The CBOR metadata and content bytes are taken verbatim from that test.
+    //
+    // TODO: Replace with a real mainnet/testnet transaction when one exists.
+    it('should parse an ord inscription envelope (FAKE -- from Counterparty regtest test data)', () => {
+      const txn = readTransaction('counterparty_regtest_ord_envelope_fairminter');
+      const result = CounterpartyParserService.parse(txn)!;
+
+      expect(result.type).toBe(DigitalArtifactType.Counterparty);
+      expect(result.encoding).toBe('p2tr');
+      expect(result.messageTypeId).toBe(90);
+      expect(result.messageType).toBe('fairminter');
+
+      // The re-encoded CBOR contains: fairminter fields + "text/plain" + content bytes
+      expect(result.getMessageData().length).toBe(77);
+    });
+  });
+
+  // ===========================================================================
+  // 4-byte message type ID (pre-short_tx_type_id, before block 489,956)
+  // ===========================================================================
+
+  describe('parse — 4-byte message type ID', () => {
+    // Classic send (ID 0) via OP_RETURN -- uses 4-byte big-endian encoding (00 00 00 00)
+    // Block 489,000 (before short_tx_type_id activation at 489,956)
+    // Sends 2,100,000,000 TRIGGERS
+    const CLASSIC_SEND_TXID = '6335eefb68f5e57eddb95b329c368615e53cf5efe346be14d271c88a63b5461e';
+
+    it('should parse a classic send (ID 0, 4-byte encoding) via OP_RETURN', () => {
+      const txn = readTransaction(CLASSIC_SEND_TXID);
+      const result = CounterpartyParserService.parse(txn)!;
+
+      expect(result.encoding).toBe('opreturn');
+      expect(result.messageTypeId).toBe(0);
+      expect(result.messageType).toBe('send');
+
+      // Classic send payload: asset_id (8 bytes BE) + quantity (8 bytes BE) = 16 bytes
+      // API raw data: 20 bytes = 4 bytes type ID (00000000) + 16 bytes payload
+      expect(result.getMessageData().length).toBe(16);
+    });
+
+    it('should parse a broadcast (ID 30, 4-byte encoding) via multisig (OLGA)', () => {
+      // OLGA predates short_tx_type_id -- uses 4-byte encoding even for ID 30
+      // API raw data: 9136 bytes = 4 bytes type ID (0000001e) + 9132 bytes payload
+      const txn = readTransaction(OLGA_MULTISIG_TXID);
+      const result = CounterpartyParserService.parse(txn)!;
+
+      expect(result.messageTypeId).toBe(30);
+      expect(result.getMessageData().length).toBe(9132);
+    });
+  });
+
+  // ===========================================================================
+  // Early exit correctness — reject non-Counterparty OP_RETURN transactions
+  // ===========================================================================
+
+  describe('early exits', () => {
+    // Rune OP_RETURN starts with 6a5d (OP_RETURN + OP_PUSHNUM_13)
+    // Our code rejects byte[1] > 0x4e before ARC4 decryption
+    const RUNE_TXID = '1af2a846befbfac4091bf540adad4fd1a86604c26c004066077d5fe22510e99b';
+
+    // Short OP_RETURN (8 hex chars = 4 bytes, below our 22 hex char minimum)
+    const SHORT_OP_RETURN_TXID = '28baf9374797230174803b0c3f63fd39e22bb1972a25cc2af4e791ca8fc89dae';
+
+    it('should reject a Rune transaction (OP_PUSHNUM_13 early exit)', () => {
+      const txn = readTransaction(RUNE_TXID);
+      expect(CounterpartyParserService.parse(txn)).toBeNull();
+    });
+
+    it('should reject a short OP_RETURN transaction (< 22 hex chars)', () => {
+      const txn = readTransaction(SHORT_OP_RETURN_TXID);
+      expect(CounterpartyParserService.parse(txn)).toBeNull();
+    });
   });
 });

testdata/tx_6335eefb68f5e57eddb95b329c368615e53cf5efe346be14d271c88a63b5461e.json

@@ -0,0 +1 @@
+{"txid":"6335eefb68f5e57eddb95b329c368615e53cf5efe346be14d271c88a63b5461e","version":1,"locktime":0,"vin":[{"txid":"fc6b1ffbfa0a9a48268a509c2664f26148d0cc965929836235491975d9312a7e","vout":2,"prevout":{"scriptpubkey":"76a9145884d72365ca5280b817de42476a9a56528ad7c088ac","scriptpubkey_asm":"OP_DUP OP_HASH160 OP_PUSHBYTES_20 5884d72365ca5280b817de42476a9a56528ad7c0 OP_EQUALVERIFY OP_CHECKSIG","scriptpubkey_type":"p2pkh","scriptpubkey_address":"1953bnyqwmLmrVfbx6n6TjkBomkwkp8Lie","value":1762976},"scriptsig":"4830450221008de8c538522bdb3b2a06ad7b3d90c71b616d3596ded07a1650f6bcb6362e79f9022018cbe23d5abe2a0546bb6be6014c363fc736b135eeb48823dda0aed92e06d3d8012103d6cecd548977c160a059e64895b423f8e73cfca3ec9eee96c3e3e9369aa337c7","scriptsig_asm":"OP_PUSHBYTES_72 30450221008de8c538522bdb3b2a06ad7b3d90c71b616d3596ded07a1650f6bcb6362e79f9022018cbe23d5abe2a0546bb6be6014c363fc736b135eeb48823dda0aed92e06d3d801 OP_PUSHBYTES_33 03d6cecd548977c160a059e64895b423f8e73cfca3ec9eee96c3e3e9369aa337c7","is_coinbase":false,"sequence":4294967295}],"vout":[{"scriptpubkey":"76a91451acdda2dc2ce3e96e48fa4ae0315e58042c462f88ac","scriptpubkey_asm":"OP_DUP OP_HASH160 OP_PUSHBYTES_20 51acdda2dc2ce3e96e48fa4ae0315e58042c462f OP_EQUALVERIFY OP_CHECKSIG","scriptpubkey_type":"p2pkh","scriptpubkey_address":"18SrpTp5otmJB8cprbsJb2HbmC6P3A7C7R","value":5430},{"scriptpubkey":"6a1c399752ffafe57a98080a8608ac82464e36b85ce5c7ccaaf04806760d","scriptpubkey_asm":"OP_RETURN OP_PUSHBYTES_28 399752ffafe57a98080a8608ac82464e36b85ce5c7ccaaf04806760d","scriptpubkey_type":"op_return","value":0},{"scriptpubkey":"76a9145884d72365ca5280b817de42476a9a56528ad7c088ac","scriptpubkey_asm":"OP_DUP OP_HASH160 OP_PUSHBYTES_20 5884d72365ca5280b817de42476a9a56528ad7c0 OP_EQUALVERIFY OP_CHECKSIG","scriptpubkey_type":"p2pkh","scriptpubkey_address":"1953bnyqwmLmrVfbx6n6TjkBomkwkp8Lie","value":1714373}],"size":265,"weight":1060,"sigops":8,"fee":43173,"status":{"confirmed":true,"block_height":489000,"block_hash":"000000000000000000cd2640a061b810e668e029d63b37645a59e8caf8fc11f4","block_time":1507530156}}

testdata/tx_counterparty_regtest_ord_envelope_fairminter.json

@@ -0,0 +1,38 @@
+{
+  "txid": "counterparty_regtest_ord_envelope_fairminter",
+  "version": 2,
+  "locktime": 0,
+  "vin": [
+    {
+      "txid": "52e8a861037edf4af1316878865e256d83680c65fcc72efc78a6ffe1d972fbd9",
+      "vout": 0,
+      "prevout": {
+        "scriptpubkey": "512079be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+        "scriptpubkey_type": "v1_p2tr",
+        "value": 100000
+      },
+      "scriptsig": "",
+      "witness": [
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+        "0063036f726401070378637001010a746578742f706c61696e01053092185a1b000018c0fdcdeb5f0000010a001903e818641a000c35001a000dbba018321a000cf8501a00989680f4f4f5f50013756e6520617373657420737570657220746f70682079be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798ac",
+        "c179be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798"
+      ],
+      "sequence": 4294967295
+    }
+  ],
+  "vout": [
+    {
+      "scriptpubkey": "6a08434e545250525459",
+      "scriptpubkey_type": "op_return",
+      "value": 0
+    }
+  ],
+  "size": 300,
+  "weight": 600,
+  "fee": 330,
+  "status": {
+    "confirmed": true,
+    "block_height": 999999,
+    "block_hash": "0000000000000000000000000000000000000000000000000000000000000000"
+  }
+}