URI: 
       tbitcoin.py: implement add_number_to_script. - electrum - Electrum Bitcoin wallet
  HTML git clone https://git.parazyd.org/electrum
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   DIR Files
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       ---
   DIR commit b3110b3b468e90cd6bcc3dfc5e83d7c991dc23fa
   DIR parent 4b89b1e270e0730d3b7a811f950663439d3864ac
  HTML Author: SomberNight <somber.night@protonmail.com>
       Date:   Sat, 14 Apr 2018 16:27:32 +0200
       
       bitcoin.py: implement add_number_to_script.
       
       Diffstat:
         M lib/bitcoin.py                      |      29 +++++++++++++++++++++++++++++
         M lib/tests/test_bitcoin.py           |      42 +++++++++++++++++++++++++++++--
       
       2 files changed, 69 insertions(+), 2 deletions(-)
       ---
   DIR diff --git a/lib/bitcoin.py b/lib/bitcoin.py
       t@@ -198,6 +198,35 @@ def op_push(i):
            else:
                return '4e' + int_to_hex(i,4)
        
       +
       +def add_data_to_script(data):
       +    """Returns pushed data to the script, automatically
       +    choosing canonical opcodes depending on the length of the data.
       +    bytes -> bytes
       +
       +    ported from https://github.com/btcsuite/btcd/blob/fdc2bc867bda6b351191b5872d2da8270df00d13/txscript/scriptbuilder.go#L128
       +    """
       +    assert_bytes(data)
       +    from .transaction import opcodes
       +
       +    data_len = len(data)
       +
       +    # "small integer" opcodes
       +    if data_len == 0 or data_len == 1 and data[0] == 0:
       +        return bytes([opcodes.OP_0])
       +    elif data_len == 1 and data[0] <= 16:
       +        return bytes([opcodes.OP_1 - 1 + data[0]])
       +    elif data_len == 1 and data[0] == 0x81:
       +        return bytes([opcodes.OP_1NEGATE])
       +
       +    return bfh(push_script(bh2u(data)))
       +
       +
       +def add_number_to_script(i):
       +    """int -> bytes"""
       +    return add_data_to_script(bfh(script_num_to_hex(i)))
       +
       +
        def push_script(x):
            return op_push(len(x)//2) + x
        
   DIR diff --git a/lib/tests/test_bitcoin.py b/lib/tests/test_bitcoin.py
       t@@ -12,7 +12,8 @@ from lib.bitcoin import (
            verify_message, deserialize_privkey, serialize_privkey, is_segwit_address,
            is_b58_address, address_to_scripthash, is_minikey, is_compressed, is_xpub,
            xpub_type, is_xprv, is_bip32_derivation, seed_type, EncodeBase58Check,
       -    script_num_to_hex)
       +    script_num_to_hex, add_data_to_script, add_number_to_script)
       +from lib.transaction import opcodes
        from lib.util import bfh
        from lib import constants
        
       t@@ -166,6 +167,43 @@ class Test_bitcoin(unittest.TestCase):
                self.assertEqual(script_num_to_hex(32768), '008000')
                self.assertEqual(script_num_to_hex(-32768), '008080')
        
       +    def test_add_data_to_script(self):
       +        # https://github.com/bitcoin/bips/blob/master/bip-0062.mediawiki#push-operators
       +        self.assertEqual(add_data_to_script(bfh('')), bytes([opcodes.OP_0]))
       +        self.assertEqual(add_data_to_script(bfh('07')), bytes([opcodes.OP_7]))
       +        self.assertEqual(add_data_to_script(bfh('10')), bytes([opcodes.OP_16]))
       +        self.assertEqual(add_data_to_script(bfh('81')), bytes([opcodes.OP_1NEGATE]))
       +        self.assertEqual(add_data_to_script(bfh('11')), bfh('0111'))
       +        self.assertEqual(add_data_to_script(bfh(75 * '42')), bfh('4b' + 75 * '42'))
       +        self.assertEqual(add_data_to_script(bfh(76 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('4c' + 76 * '42'))
       +        self.assertEqual(add_data_to_script(bfh(100 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('64' + 100 * '42'))
       +        self.assertEqual(add_data_to_script(bfh(255 * '42')), bytes([opcodes.OP_PUSHDATA1]) + bfh('ff' + 255 * '42'))
       +        self.assertEqual(add_data_to_script(bfh(256 * '42')), bytes([opcodes.OP_PUSHDATA2]) + bfh('0001' + 256 * '42'))
       +        self.assertEqual(add_data_to_script(bfh(520 * '42')), bytes([opcodes.OP_PUSHDATA2]) + bfh('0802' + 520 * '42'))
       +
       +    def test_add_number_to_script(self):
       +        # https://github.com/bitcoin/bips/blob/master/bip-0062.mediawiki#numbers
       +        self.assertEqual(add_number_to_script(0), bytes([opcodes.OP_0]))
       +        self.assertEqual(add_number_to_script(7), bytes([opcodes.OP_7]))
       +        self.assertEqual(add_number_to_script(16), bytes([opcodes.OP_16]))
       +        self.assertEqual(add_number_to_script(-1), bytes([opcodes.OP_1NEGATE]))
       +        self.assertEqual(add_number_to_script(-127), bfh('01ff'))
       +        self.assertEqual(add_number_to_script(-2), bfh('0182'))
       +        self.assertEqual(add_number_to_script(17), bfh('0111'))
       +        self.assertEqual(add_number_to_script(127), bfh('017f'))
       +        self.assertEqual(add_number_to_script(-32767), bfh('02ffff'))
       +        self.assertEqual(add_number_to_script(-128), bfh('028080'))
       +        self.assertEqual(add_number_to_script(128), bfh('028000'))
       +        self.assertEqual(add_number_to_script(32767), bfh('02ff7f'))
       +        self.assertEqual(add_number_to_script(-8388607), bfh('03ffffff'))
       +        self.assertEqual(add_number_to_script(-32768), bfh('03008080'))
       +        self.assertEqual(add_number_to_script(32768), bfh('03008000'))
       +        self.assertEqual(add_number_to_script(8388607), bfh('03ffff7f'))
       +        self.assertEqual(add_number_to_script(-2147483647), bfh('04ffffffff'))
       +        self.assertEqual(add_number_to_script(-8388608 ), bfh('0400008080'))
       +        self.assertEqual(add_number_to_script(8388608), bfh('0400008000'))
       +        self.assertEqual(add_number_to_script(2147483647), bfh('04ffffff7f'))
       +
            def test_address_to_script(self):
                # bech32 native segwit
                # test vectors from BIP-0173
       t@@ -520,7 +558,7 @@ class Test_seeds(unittest.TestCase):
                ('  fRoSt pig brisk excIte novel rePort CamEra enlist axis nation nOVeL dEsert ', 'segwit'),
                ('9dk', 'segwit'),
            }
       -    
       +
            def test_new_seed(self):
                seed = "cram swing cover prefer miss modify ritual silly deliver chunk behind inform able"
                self.assertTrue(is_new_seed(seed))