blocktrail / blocktrail-sdk-nodejs

var assert = require('assert');

var bitcoin = require('bitcoinjs-lib');

var SizeEstimation = require("../lib/size_estimation");

function makeUtxo(script, rs, ws) {

    var utxo = {

        scriptpubkey_hex: script.toString('hex'),

        value: 100000000

    };

        utxo.redeem_script = rs.toString('hex');

    }

    if (ws instanceof Buffer) {

        utxo.witness_script = ws.toString('hex');

    }

    return utxo;

}

function scriptUtxos(script) {

    var hash160 = bitcoin.crypto.hash160(script);

    var p2shSPK = bitcoin.script.scriptHash.output.encode(hash160);

    var sha256 = bitcoin.crypto.sha256(script);

    var p2wshSPK = bitcoin.script.witnessScriptHash.output.encode(sha256);

    var p2wshHash160 = bitcoin.crypto.hash160(p2wshSPK);

    var p2wshP2sh = bitcoin.script.scriptHash.output.encode(p2wshHash160);

    var bareUtxo = makeUtxo(script, null, null);

    var p2shUtxo = makeUtxo(p2shSPK, script, null);

    var p2wshUtxo = makeUtxo(p2wshSPK, null, script);

    var p2shP2wshUtxo = makeUtxo(p2wshP2sh, p2wshSPK, script);

    return {

        bareUtxo: bareUtxo,

        p2shUtxo: p2shUtxo,

        p2wshUtxo: p2wshUtxo,

        p2shP2wshUtxo: p2shP2wshUtxo

    };

}

function makeUtxoFixtures(script, scriptSizes, extra) {

    var utxos = scriptUtxos(script);

    var result = [

        [utxos.bareUtxo, scriptSizes.bareSig, 0],

        [utxos.p2shUtxo, scriptSizes.p2shSig, 0],

        [utxos.p2wshUtxo, 1, scriptSizes.nestedWit],

        [utxos.p2shP2wshUtxo, scriptSizes.nestedSig, scriptSizes.nestedWit]

    ];

    if (Array.isArray(extra) && extra.length > 0) {

        for (var i = 0; i < result.length; i++) {

            result[i] = result[i].concat(extra);

        }

    }

    return result;

}

function makeFormFixtures(script, scriptSizes, extra) {

    var result = [

        [script, false, null, null, scriptSizes.bareSig, 0],

        [script, false, script, null, scriptSizes.p2shSig, 0],

        [script, true, null, script, 1, scriptSizes.nestedWit],

        [script, true, scriptSizes.p2wshScript, script, scriptSizes.nestedSig, scriptSizes.nestedWit]

    ];

    if (Array.isArray(extra) && extra.length > 0) {

        for (var i = 0; i < result.length; i++) {

            result[i] = result[i].concat(extra);

        }

    }

    return result;

}

function p2pkScriptSizes(script) {

    var bareSize = (1 + SizeEstimation.SIZE_DER_SIGNATURE);

    var bareSig = 1 + bareSize;

    var p2shSig = 1 + bareSize + 1 + script.length;

    var p2wshHash = bitcoin.crypto.sha256(script);

    var p2wshScript = bitcoin.script.witnessScriptHash.output.encode(p2wshHash);

    var nestedSig = 1 + 1 + p2wshScript.length;

    var witSize = (1 + SizeEstimation.SIZE_DER_SIGNATURE);

    var nestedWit = witSize + 1 + 1 + script.length;

    return {

        bareSig: bareSig,

        p2shSig: p2shSig,

        p2wshScript: p2wshScript,

        nestedSig: nestedSig,

        nestedWit: nestedWit

    };

}

function p2pkMakeScript(wif, network) {

    var uncompressed = bitcoin.ECPair.fromWIF(wif, network);

    var keyu = uncompressed.getPublicKeyBuffer();

    return bitcoin.script.pubKey.output.encode(keyu);

}

function p2pkhScriptSizes(script, compressed) {

    var bareSize = (1 + SizeEstimation.SIZE_DER_SIGNATURE) + (1 + (compressed ? 33 : 65));

    var bareSig = 1 + bareSize;

    var p2shSig = 1 + bareSize + 1 + script.length;

    var p2wshHash = bitcoin.crypto.sha256(script);

    var p2wshScript = bitcoin.script.witnessScriptHash.output.encode(p2wshHash);

    var nestedSig = 1 + 1 + p2wshScript.length;

    var witSize = (1 + SizeEstimation.SIZE_DER_SIGNATURE) + (1 + (compressed ? 33 : 65));

    var nestedWit = witSize + 1 + 1 + script.length;

    return {

        bareSig: bareSig,

        p2shSig: p2shSig,

        p2wshScript: p2wshScript,

        nestedSig: nestedSig,

        nestedWit: nestedWit

    };

}

    var eckey = bitcoin.ECPair.fromWIF(wif, network);

    var hash160 = bitcoin.crypto.hash160(eckey.getPublicKeyBuffer());

    return bitcoin.script.pubKeyHash.output.encode(hash160);

}

function p2pkhFormFixture(wif, network) {

    var keyHash = p2pkhMakeScript(wif, network);

    var compressed = bitcoin.ECPair.fromWIF(wif, network).compressed;

    var scriptSizes = p2pkhScriptSizes(keyHash, compressed);

    return makeFormFixtures(keyHash, scriptSizes, [compressed]);

}

function p2pkMakeFormFixtures(wif, network) {

    var script = p2pkMakeScript(wif, network);

    var scriptSizes = p2pkScriptSizes(script);

    return makeFormFixtures(script, scriptSizes);

}

function multisigMakeScript(m, wifs, network) {

    var keys = wifs.map(function(wif) {

        return bitcoin.ECPair.fromWIF(wif, network).getPublicKeyBuffer();

    });

    return bitcoin.script.multisig.output.encode(m, keys);

}

function multisigScriptSizes(m, script) {

    var bareSize = 1/*op0*/ + m * (1 + SizeEstimation.SIZE_DER_SIGNATURE);

    var bareSig = 1 + bareSize;

    var p2shSig = bareSize + SizeEstimation.getLengthForScriptPush(script.length) + script.length;

    var p2wshHash = bitcoin.crypto.sha256(script);

    var p2wshScript = bitcoin.script.witnessScriptHash.output.encode(p2wshHash);

    var nestedSig = 1 + 1 + p2wshScript.length;

    var witSize = 1 + m * (1 + SizeEstimation.SIZE_DER_SIGNATURE);

    var nestedWit = witSize + 1 + 1 + script.length;

    return {

        bareSig: bareSig,

        p2shSig: SizeEstimation.getLengthForVarInt(p2shSig) + p2shSig,

        p2wshScript: p2wshScript,

        nestedSig: nestedSig,

        nestedWit: nestedWit

    };

}

var varIntFixtures = [

    [0, 1],

    [1, 1],

    [252, 1],

    [253, 3],

    [254, 3],

    [65534, 3],

    [65535, 5],

    [65536, 5],

    [Math.pow(2, 31), 5],

    [Math.pow(2, 32) - 2, 5],

    [Math.pow(2, 32) - 1, 9],

    [Math.pow(2, 32), 9],

    // don't go above this, is signed int territory, PHP complains

    // nodejs?

    [0x7fffffffffffffff, 9]

];

var scriptDataLenFixtures =  [

    [0, 1],

    [1, 1],

    [74, 1],

    [75, 2],

    [76, 2],

    [254, 2],

    [255, 2],

    [256, 3],

    [65534, 3],

    [65535, 3],

    [65536, 5]

];

var p2pkStackFixtures = (function() {

    var u = '5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp';

    var c = 'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd';

    var fixtures = [];

    fixtures.push([p2pkMakeScript(u, bitcoin.networks.bitcoin)]);

    fixtures.push([p2pkMakeScript(c, bitcoin.networks.bitcoin)]);

    return fixtures;

})();

// test fixtures of every possible representation of multisig

var p2pkFormFixtures = (function() {

    return []

        .concat(p2pkMakeFormFixtures('5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp', bitcoin.networks.bitcoin))

        .concat(p2pkMakeFormFixtures('L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd', bitcoin.networks.bitcoin));

})();

var p2pkhStackFixtures = (function() {

    var u = '5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp';

    var c = 'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd';

    var fixtures = [];

    fixtures.push([p2pkhMakeScript(u, bitcoin.networks.bitcoin)]);

    fixtures.push([p2pkhMakeScript(c, bitcoin.networks.bitcoin)]);

    return fixtures;

})();

// test fixtures of every possible representation of multisig

var p2pkhFormFixtures = (function() {

    return []

        .concat(p2pkhFormFixture('L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd', bitcoin.networks.bitcoin))

        .concat(p2pkhFormFixture('5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp', bitcoin.networks.bitcoin))

    ;

})();

var multisigStackFixtures = (function() {

    var u = ['5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp',

        '5KCV94YBsrJWTdk6cQWJxEd25sH8h1cGTpJnCN6kLMLe4c3QZVr',

        '5JUxGateMWVBsBQkAwSRQLxyaQXhsch4EStfC62cqdEf2zUheVT'

    ];

    var c = ['L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

        'KwUZpCvpAkUe1SZj3k3P2acta1V1jY8Dpuj71bEAukEKVrg8NEym',

        'Kz2Lm2hzjPWhv3WW9Na5HUKi4qBxoTfv8fNYAU6KV6TZYVGdK5HW'

    ];

    var uncompressed = u.map(function(wif) {

        return bitcoin.ECPair.fromWIF(wif, bitcoin.networks.bitcoin);

    });

    var compressed = c.map(function(wif) {

        return bitcoin.ECPair.fromWIF(wif, bitcoin.networks.bitcoin);

    });

    var fixtures = [];

    for (var i = 0; i < 3; i++) {

        var keys = [];

        var j;

        for (j = 0; j < i; j++) {

            keys.push(uncompressed[j].getPublicKeyBuffer());

        }

        for (j = i; j < 3; j++) {

            keys.push(compressed[j].getPublicKeyBuffer());

        }

        fixtures.push([bitcoin.script.multisig.output.encode(2, keys)]);

    }

    return fixtures;

})();

// test fixtures of every possible representation of multisig

var multisigFormFixtures = (function() {

    var multisig = multisigMakeScript(2, ['L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

        'KwUZpCvpAkUe1SZj3k3P2acta1V1jY8Dpuj71bEAukEKVrg8NEym',

        'Kz2Lm2hzjPWhv3WW9Na5HUKi4qBxoTfv8fNYAU6KV6TZYVGdK5HW'

    ], bitcoin.networks.bitcoin);

    var msDetail = multisigScriptSizes(2, multisig);

    return []

        .concat(makeFormFixtures(multisig, msDetail));

})();

// test fixtures of every possible representation of multisig

var multisigUtxoFixtures = (function() {

    var data = [

        [

            2,

            [

                'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

                'KwUZpCvpAkUe1SZj3k3P2acta1V1jY8Dpuj71bEAukEKVrg8NEym',

                'Kz2Lm2hzjPWhv3WW9Na5HUKi4qBxoTfv8fNYAU6KV6TZYVGdK5HW'

            ],

            bitcoin.networks.bitcoin

        ],

        [

            3,

            [

                'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

                'KwUZpCvpAkUe1SZj3k3P2acta1V1jY8Dpuj71bEAukEKVrg8NEym',

                'Kz2Lm2hzjPWhv3WW9Na5HUKi4qBxoTfv8fNYAU6KV6TZYVGdK5HW'

            ],

            bitcoin.networks.bitcoin

        ],

        [

            1,

            [

                'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd'

            ],

            bitcoin.networks.bitcoin

        ]

    ];

    var fixtures = [];

    data.map(function(fixture) {

        var script = multisigMakeScript(fixture[0], fixture[1], fixture[2]);

        var msDetail = multisigScriptSizes(fixture[0], script);

        makeUtxoFixtures(script, msDetail).map(function(fixture) {

            fixtures.push(fixture);

        });

    });

    return fixtures;

})();

// test fixtures of every possible representation of multisig

var p2pkUtxoFixtures = (function() {

    var data = [

        [

            'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

            bitcoin.networks.bitcoin

        ],

        [

            'KwUZpCvpAkUe1SZj3k3P2acta1V1jY8Dpuj71bEAukEKVrg8NEym',

            bitcoin.networks.bitcoin

        ],

        [

            'Kz2Lm2hzjPWhv3WW9Na5HUKi4qBxoTfv8fNYAU6KV6TZYVGdK5HW',

            bitcoin.networks.bitcoin

        ]

    ];

    var fixtures = [];

    data.map(function(fixture) {

        var script = p2pkMakeScript(fixture[0], fixture[1]);

        var msDetail = p2pkScriptSizes(script);

        makeUtxoFixtures(script, msDetail).map(function(fixture) {

            fixtures.push(fixture);

        });

    });

    return fixtures;

})();

// test fixtures of every possible representation of multisig

var p2pkhUtxoFixtures = (function() {

    var data = [

        [

            'L1Tr4rPUi81XN1Dp48iuva5U9sWxU1eipgiAu8BhnB3xnSfGV5rd',

            bitcoin.networks.bitcoin

        ]

    ];

    var fixtures = [];

    data.map(function(fixture) {

        var script = p2pkhMakeScript(fixture[0], fixture[1]);

        var compressed = bitcoin.ECPair.fromWIF(fixture[0], fixture[1]).compressed;

        var msDetail = p2pkhScriptSizes(script, compressed);

        makeUtxoFixtures(script, msDetail, [compressed]).map(function(fixture) {

            fixtures.push(fixture);

        });

    });

    return fixtures;

})();

describe('SizeEstimation.getLengthForVarInt', function() {

    varIntFixtures.map(function(fixture) {

        var inputLen = fixture[0];

        var expectSize = fixture[1];

        it('works for `' + inputLen + '` (equals ' + expectSize + ')', function(cb) {

            var result = SizeEstimation.getLengthForVarInt(inputLen);

            assert.equal(expectSize, result);

            cb();

        });

    });

    it('throws when too large an input is provided', function(cb) {

        var err;

        try {

            SizeEstimation.getLengthForVarInt(0xffffffffffffffff + 1);

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Size of varint too large");

        cb();

    });

});

describe('SizeEstimation.getLengthForScriptPush', function() {

    scriptDataLenFixtures.map(function(fixture) {

        var inputLen = fixture[0];

        var expectSize = fixture[1];

        it(' works for ' + inputLen + '` (equals ' + expectSize + ')', function(cb) {

            var result = SizeEstimation.getLengthForScriptPush(inputLen);

            assert.equal(expectSize, result);

            cb();

        });

    });

    it('throws when too large an input is provided', function(cb) {

        var err;

        try {

            SizeEstimation.getLengthForScriptPush(0xffffffff + 1);

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Size of pushdata too large");

        cb();

    });

});

describe('estimateP2PKStackSize', function() {

    p2pkStackFixtures.map(function(fixture) {

        it("works for p2pk scripts with the keys", function(cb) {

            var script = fixture[0];

            assert.ok(bitcoin.script.pubKey.output.check(script));

            var decoded = bitcoin.script.pubKey.output.decode(script);

            var estimation = SizeEstimation.estimateP2PKStackSize(decoded);

            assert.equal("object", typeof estimation);

            assert.equal(2, estimation.length);

            var scriptSize = estimation[1];

            assert.equal(script.length, scriptSize);

            var stackSizes = estimation[0];

            assert.equal(1, stackSizes.length);

            assert.equal(SizeEstimation.SIZE_DER_SIGNATURE, stackSizes[0]);

            cb();

        });

    });

    p2pkFormFixtures.map(function(fixture) {

        it("deals with different representations", function(cb) {

            var script = fixture[0];

            var isWit = fixture[1];

            var rs = fixture[2];

            var ws = fixture[3];

            var expectSig = fixture[4];

            var expectWit = fixture[5];

            assert.ok(bitcoin.script.pubKey.output.check(script));

            var decoded = bitcoin.script.pubKey.output.decode(script);

            var stackEst = SizeEstimation.estimateP2PKStackSize(decoded);

            var stackSizes = stackEst[0];

            var est = SizeEstimation.estimateStackSignatureSize(stackSizes, isWit, rs, ws);

            assert.equal("object", typeof est);

            assert.equal(2, est.length);

            var foundSigSize = est[0];

            var foundWitSize = est[1];

            assert.equal(foundSigSize, expectSig);

            assert.equal(foundWitSize, expectWit);

            cb();

        });

    });

});

describe('estimateP2PKHStackSize', function() {

    p2pkhStackFixtures.map(function(fixture) {

        it("works for p2pkh scripts with the keys", function(cb) {

            var script = fixture[0];

            assert.ok(bitcoin.script.pubKeyHash.output.check(script));

            var decoded = bitcoin.script.pubKeyHash.output.decode(script);

            var estimation = SizeEstimation.estimateP2PKHStackSize(decoded);

            assert.equal("object", typeof estimation);

            assert.equal(2, estimation.length);

            var scriptSize = estimation[1];

            assert.equal(scriptSize, script.length);

            var stackSizes = estimation[0];

            assert.equal(2, stackSizes.length);

            assert.equal(stackSizes[0], SizeEstimation.SIZE_DER_SIGNATURE);

            assert.equal(stackSizes[1], 33);

            cb();

        });

    });

    p2pkhFormFixtures.map(function(fixture) {

        it("deals with different representations", function(cb) {

            var script = fixture[0];

            var isWit = fixture[1];

            var rs = fixture[2];

            var ws = fixture[3];

            var expectSig = fixture[4];

            var expectWit = fixture[5];

            var compressed = fixture[6];

            assert.ok(bitcoin.script.pubKeyHash.output.check(script));

            var stackEst = SizeEstimation.estimateP2PKHStackSize(compressed);

            var stackSizes = stackEst[0];

            var est = SizeEstimation.estimateStackSignatureSize(stackSizes, isWit, rs, ws);

            assert.equal("object", typeof est);

            assert.equal(2, est.length);

            var foundSigSize = est[0];

            var foundWitSize = est[1];

            assert.equal(foundSigSize, expectSig);

            assert.equal(foundWitSize, expectWit);

            cb();

        });

    });

});

describe("estimateMultisigStackSize", function() {

    multisigStackFixtures.map(function(fixture) {

        it("works for multisig scripts with the keys", function(cb) {

            var script = fixture[0];

            assert.ok(bitcoin.script.multisig.output.check(script));

            var decoded = bitcoin.script.multisig.output.decode(script);

            var estimation = SizeEstimation.estimateMultisigStackSize(decoded.m, decoded.pubKeys);

            assert.equal("object", typeof estimation);

            assert.equal(2, estimation.length);

            var scriptSize = estimation[1];

            assert.equal(script.length, scriptSize);

            var stackSizes = estimation[0];

            assert.equal(1 + decoded.m, stackSizes.length);

            assert.equal(0, stackSizes[0]);

            for (var i = 0; i < decoded.m; i++) {

                assert.equal(SizeEstimation.SIZE_DER_SIGNATURE, stackSizes[1 + i]);

            }

            cb();

        });

    });

    multisigFormFixtures.map(function(fixture) {

        it("deals with different representations", function(cb) {

            var script = fixture[0];

            var isWit = fixture[1];

            var rs = fixture[2];

            var ws = fixture[3];

            var expectSig = fixture[4];

            var expectWit = fixture[5];

            assert.ok(bitcoin.script.multisig.output.check(script));

            var multisig = bitcoin.script.multisig.output.decode(script);

            var stackEst = SizeEstimation.estimateMultisigStackSize(multisig.m, multisig.pubKeys);

            var stackSizes = stackEst[0];

            var est = SizeEstimation.estimateStackSignatureSize(stackSizes, isWit, rs, ws);

            assert.equal("object", typeof est);

            assert.equal(2, est.length);

            var foundSigSize = est[0];

            var foundWitSize = est[1];

            assert.equal(foundSigSize, expectSig);

            assert.equal(foundWitSize, expectWit);

            cb();

        });

    });

});

describe("SizeEstimation.estimateInputFromScripts", function() {

    it('throws on invalid script type', function(cb) {

        var err;

        try {

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Unsupported script type");

        cb();

    });

});

describe("SizeEstimation.estimateOutputs", function() {

    [0, 1, 5, 9].map(function(size) {

        it("estimates single output, for script size " + size, function(cb) {

            var script = '';

            for (var i = 0; i < size; i++) {

                script = script + '6a';

            }

            var outputsSize = SizeEstimation.calculateOutputsSize([{

                value: 1234,

                script: script

            }]);

            assert.equal(outputsSize, 8 + 1 + size);

            cb();

        });

    });

});

describe("SizeEstimation.estimateTxWeight", function() {

    var wif = "5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp";

    var key = bitcoin.ECPair.fromWIF(wif, bitcoin.networks.bitcoin);

    var hash160 = bitcoin.crypto.hash160(key.getPublicKeyBuffer());

    var p2wpkh = bitcoin.script.witnessPubKeyHash.output.encode(hash160);

    var p2pkh = bitcoin.script.pubKeyHash.output.encode(hash160);

    it("estimates p2wpkh weight", function(cb) {

        var utxos = [

            {

                txid: "abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234",

                vout: 0,

                scriptpubkey_hex: p2wpkh

            }

        ];

        var txb = new bitcoin.TransactionBuilder();

        utxos.map(function(utxo) {

            txb.addInput(utxo.txid, utxo.vout);

        });

        txb.addOutput(p2wpkh, 1234);

        var tx = txb.buildIncomplete();

        var size = SizeEstimation.estimateTxWeight(tx, utxos);

        var vsize = SizeEstimation.estimateTxVsize(tx, utxos);

        assert.equal(Math.ceil(size / 4), vsize);

        cb();

    });

    it("weight for non-witness is 4x size", function(cb) {

        var utxos = [

            {

                txid: "abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234abcd1234",

                vout: 0,

                scriptpubkey_hex: p2pkh

            }

        ];

        var txb = new bitcoin.TransactionBuilder();

        utxos.map(function(utxo) {

            txb.addInput(utxo.txid, utxo.vout);

        });

        txb.addOutput(p2wpkh, 1234);

        var tx = txb.buildIncomplete();

        var os = SizeEstimation.calculateOutputsSize(tx.outs);

        var bs = 4 + 4 + SizeEstimation.estimateInputsSize(utxos, false) + 4 + os + 4;

        var size = SizeEstimation.estimateTxWeight(tx, utxos);

        assert.equal(size, bs * 4);

        var vsize = SizeEstimation.estimateTxVsize(tx, utxos);

        assert.equal(Math.ceil(size / 4), vsize);

        cb();

    });

});

describe("SizeEstimation.estimateInputsSize", function() {

    var wif = "5KW8Ymmu8gWManGggZZQJeX7U3pn5HtcqqsVrNUbc1SUmVPZbwp";

    var key = bitcoin.ECPair.fromWIF(wif, bitcoin.networks.bitcoin);

    var hash160 = bitcoin.crypto.hash160(key.getPublicKeyBuffer());

    var p2wpkh = bitcoin.script.witnessPubKeyHash.output.encode(hash160);

    it("drops witness based on parameter", function(cb) {

        var withWitness = SizeEstimation.estimateInputsSize([{

            value: 1234,

            scriptpubkey_hex: p2wpkh

        }], true);

        var noWitness = SizeEstimation.estimateInputsSize([{

            value: 1234,

            scriptpubkey_hex: p2wpkh

        }], false);

        assert.equal(noWitness, 32 + 4 + 4 + 1);

        /*witness flags + witness vector*/

        var assumeSize = noWitness + 2 + (1 + 1 + SizeEstimation.SIZE_DER_SIGNATURE + 1 + 33);

        assert.ok(assumeSize === withWitness);

        cb();

    });

});

describe("SizeEstimation.estimateUtxo", function() {

    it("throws if P2SH and redeemScript not provided", function(cb) {

        var err;

        try {

            var spk = bitcoin.script.scriptHash.output.encode(hash160);

            SizeEstimation.estimateUtxo({

                scriptpubkey_hex: spk,

                redeem_script: null

            });

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Cant estimate, missing redeem script");

        cb();

    });

    it("throws if P2WSH and witnessScript not provided", function(cb) {

        var err;

        try {

            var spk = bitcoin.script.witnessScriptHash.output.encode(hash160);

            SizeEstimation.estimateUtxo({

                scriptpubkey_hex: spk,

                witness_script: null

            });

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Can't estimate, missing witness script");

        cb();

    });

    it("throws if unsupported script type", function(cb) {

        var err;

        try {

            SizeEstimation.estimateUtxo({

                scriptpubkey_hex: spk,

                witness_script: null

            });

        } catch (e) {

            err = e;

        }

        assert.equal(err.message, "Unsupported script type");

        cb();

    });

    []

        .concat(multisigUtxoFixtures)

        .concat(p2pkUtxoFixtures)

        .concat(p2pkhUtxoFixtures)

        .map(function(fixture) {

            it("deals with different representations", function(cb) {

                var utxo = fixture[0];

                var expectSig = fixture[1];

                var expectWit = fixture[2];

                var compressed = false;

                if (typeof fixture[3] === "boolean") {

                    compressed = fixture[3];

                }

                var estimate = SizeEstimation.estimateUtxo(utxo, compressed);

                assert.equal(estimate.scriptSig, expectSig);

                assert.equal(estimate.witness, expectWit);

                cb();

            });

        });

});

describe("estimateWitnessPubKeyHash", function() {

    it('should work', function(cb) {

        var utxo = { hash: '4141414141414141414141414141414141414141414141414141414141414141',

            idx: 2,

            scriptpubkey_hex: '00140102030401020304010203040102030401020304',

            value: 1,

            confirmations: 1,

            sign_mode: 'dont_sign',

            address: '2N245vnpchbFYWm5hZ6hqF2zC8QbVpoHeSU',

            path: null,

            redeem_script: null,

            witness_script: null,

            green: null };

        var estimation = SizeEstimation.estimateUtxo(utxo);

        assert.equal(1, estimation.scriptSig);

        assert.equal(108, estimation.witness);

        cb();

    });

});