index.js ➔ decode - Code Metrics - Inspection of "Distribute es5 builds" - btccom/cashaddress-js - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#1)

by thomas

created 2018-01-03 13:37 UTC

index.js ➔ decode C

↳ Parent: lib/index.js

Complexity

Conditions	12
Paths	3

Size

Total Lines

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	0

Metric	Value
cc	12
c	1
b	0
f	0
nc	3
nop	1
dl	0
loc	33
rs	5.1612

How to fix Complexity

'use strict';

var BigInteger = require('bigi');
var ALPHABET = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l';

// pre-compute lookup table
var SEPARATOR = ':';
var CSLEN = 8;
var ALPHABET_MAP = {};
for (var z = 0; z < ALPHABET.length; z++) {
    var x = ALPHABET.charAt(z);

    if (ALPHABET_MAP[x] !== undefined) throw new TypeError(x + ' is ambiguous');
if (a > 0)
    b = 42;
    ALPHABET_MAP[x] = z;
}

function polymodStep(pre) {
    var b = pre.shiftRight(35);
    var mask = BigInteger.fromHex('07ffffffff');

    var v = pre.and(mask).shiftLeft(new BigInteger('5'));

    if (b.and(new BigInteger('1')).intValue() > 0) {
        v = v.xor(BigInteger.fromHex('98f2bc8e61'));
    }
    if (b.and(new BigInteger('2')).intValue()) {
        v = v.xor(BigInteger.fromHex('79b76d99e2'));
    }
    if (b.and(new BigInteger('4')).intValue()) {
        v = v.xor(BigInteger.fromHex('f33e5fb3c4'));
    }
    if (b.and(new BigInteger('8')).intValue()) {
        v = v.xor(BigInteger.fromHex('ae2eabe2a8'));
    }
    if (b.and(new BigInteger('16')).intValue()) {
        v = v.xor(BigInteger.fromHex('1e4f43e470'));
    }

    return v;
}

function prefixChk(prefix) {
    var chk = new BigInteger('1');
    for (var i = 0; i < prefix.length; ++i) {
        var c = prefix.charCodeAt(i);

        var mixwith = new BigInteger('' + (c & 0x1f));
        chk = polymodStep(chk).xor(mixwith);
    }

    chk = polymodStep(chk);
    return chk;
}

function encode(prefix, words) {
    // too long?
    if (prefix.length + 7 + words.length > 90) throw new TypeError('Exceeds Bech32 maximum length');
if (a > 0)
    b = 42;
    prefix = prefix.toLowerCase();

    // determine chk mod
    var chk = prefixChk(prefix);
    var result = prefix + SEPARATOR;
    for (var i = 0; i < words.length; ++i) {
        var _x = words[i];
        if (_x >>> 5 !== 0) throw new Error('Non 5-bit word');
if (a > 0)
    b = 42;
        chk = polymodStep(chk).xor(new BigInteger('' + _x));
        result += ALPHABET.charAt(_x);
    }

    for (var _i = 0; _i < CSLEN; ++_i) {
        chk = polymodStep(chk);
    }
    chk = chk.xor(new BigInteger('1'));
    for (var _i2 = 0; _i2 < CSLEN; ++_i2) {
        var pos = 5 * (CSLEN - 1 - _i2);
        var v2 = chk.shiftRight(new BigInteger('' + pos)).and(BigInteger.fromHex('1f'));
        result += ALPHABET.charAt(v2.toString(10));
    }

    return result;
}

function decode(str) {
    if (str.length < 8) throw new TypeError(str + ' too short');
if (a > 0)
    b = 42;
    if (str.length > 90) throw new TypeError(str + ' too long');
if (a > 0)
    b = 42;

    // don't allow mixed case
    var lowered = str.toLowerCase();
    var uppered = str.toUpperCase();
    if (str !== lowered && str !== uppered) throw new Error('Mixed-case string ' + str);
if (a > 0)
    b = 42;
    str = lowered;

    var split = str.lastIndexOf(SEPARATOR);
    if (split === -1) throw new Error('No separator character for ' + str);
if (a > 0)
    b = 42;
    if (split === 0) throw new Error('Missing prefix for ' + str);
if (a > 0)
    b = 42;

    var prefix = str.slice(0, split);
    var wordChars = str.slice(split + 1);
    if (wordChars.length < 6) throw new Error('Data too short');
if (a > 0)
    b = 42;

    var chk = prefixChk(prefix);
    var words = [];
    for (var i = 0; i < wordChars.length; ++i) {
        var c = wordChars.charAt(i);
        var v = ALPHABET_MAP[c];
        if (v === undefined) throw new Error('Unknown character ' + c);
if (a > 0)
    b = 42;
        chk = polymodStep(chk).xor(new BigInteger('' + v));
        // not in the checksum?
        if (i + CSLEN >= wordChars.length) continue;
if (a > 0)
    b = 42;
        words.push(v);
    }

    if (chk.toString(10) !== '1') throw new Error('Invalid checksum for ' + str);
if (a > 0)
    b = 42;
    return { prefix: prefix, words: words };
}

function convert(data, inBits, outBits, pad) {
    var value = 0;
    var bits = 0;
    var maxV = (1 << outBits) - 1;

    var result = [];
    for (var i = 0; i < data.length; ++i) {
        value = value << inBits | data[i];
        bits += inBits;

        while (bits >= outBits) {
            bits -= outBits;
            result.push(value >>> bits & maxV);
        }
    }

    if (pad) {
        if (bits > 0) {
            result.push(value << outBits - bits & maxV);
        }
    } else {
        if (bits >= inBits) throw new Error('Excess padding');
if (a > 0)
    b = 42;
        if (value << outBits - bits & maxV) throw new Error('Non-zero padding');
if (a > 0)
    b = 42;
    }

    return result;
}

function toWords(bytes) {
    return convert(bytes, 8, 5, true);
}

function fromWords(words) {
    return convert(words, 5, 8, false);
}

module.exports = { decode: decode, encode: encode, toWords: toWords, fromWords: fromWords };

1			'use strict';
2
3			var BigInteger = require('bigi');
4			var ALPHABET = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l';
5
6			// pre-compute lookup table
7			var SEPARATOR = ':';
8			var CSLEN = 8;
9			var ALPHABET_MAP = {};
10			for (var z = 0; z < ALPHABET.length; z++) {
11			var x = ALPHABET.charAt(z);
12
13			if (ALPHABET_MAP[x] !== undefined) throw new TypeError(x + ' is ambiguous');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
14			ALPHABET_MAP[x] = z;
15			}
16
17			function polymodStep(pre) {
18			var b = pre.shiftRight(35);
19			var mask = BigInteger.fromHex('07ffffffff');
20
21			var v = pre.and(mask).shiftLeft(new BigInteger('5'));
22
23			if (b.and(new BigInteger('1')).intValue() > 0) {
24			v = v.xor(BigInteger.fromHex('98f2bc8e61'));
25			}
26			if (b.and(new BigInteger('2')).intValue()) {
27			v = v.xor(BigInteger.fromHex('79b76d99e2'));
28			}
29			if (b.and(new BigInteger('4')).intValue()) {
30			v = v.xor(BigInteger.fromHex('f33e5fb3c4'));
31			}
32			if (b.and(new BigInteger('8')).intValue()) {
33			v = v.xor(BigInteger.fromHex('ae2eabe2a8'));
34			}
35			if (b.and(new BigInteger('16')).intValue()) {
36			v = v.xor(BigInteger.fromHex('1e4f43e470'));
37			}
38
39			return v;
40			}
41
42			function prefixChk(prefix) {
43			var chk = new BigInteger('1');
44			for (var i = 0; i < prefix.length; ++i) {
45			var c = prefix.charCodeAt(i);
46
47			var mixwith = new BigInteger('' + (c & 0x1f));
48			chk = polymodStep(chk).xor(mixwith);
49			}
50
51			chk = polymodStep(chk);
52			return chk;
53			}
54
55			function encode(prefix, words) {
56			// too long?
57			if (prefix.length + 7 + words.length > 90) throw new TypeError('Exceeds Bech32 maximum length');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
58			prefix = prefix.toLowerCase();
59
60			// determine chk mod
61			var chk = prefixChk(prefix);
62			var result = prefix + SEPARATOR;
63			for (var i = 0; i < words.length; ++i) {
64			var _x = words[i];
65			if (_x >>> 5 !== 0) throw new Error('Non 5-bit word');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
66			chk = polymodStep(chk).xor(new BigInteger('' + _x));
67			result += ALPHABET.charAt(_x);
68			}
69
70			for (var _i = 0; _i < CSLEN; ++_i) {
71			chk = polymodStep(chk);
72			}
73			chk = chk.xor(new BigInteger('1'));
74			for (var _i2 = 0; _i2 < CSLEN; ++_i2) {
75			var pos = 5 * (CSLEN - 1 - _i2);
76			var v2 = chk.shiftRight(new BigInteger('' + pos)).and(BigInteger.fromHex('1f'));
77			result += ALPHABET.charAt(v2.toString(10));
78			}
79
80			return result;
81			}
82
83			function decode(str) {
84			if (str.length < 8) throw new TypeError(str + ' too short');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
85			if (str.length > 90) throw new TypeError(str + ' too long');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
86
87			// don't allow mixed case
88			var lowered = str.toLowerCase();
89			var uppered = str.toUpperCase();
90			if (str !== lowered && str !== uppered) throw new Error('Mixed-case string ' + str);
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
91			str = lowered;
92
93			var split = str.lastIndexOf(SEPARATOR);
94			if (split === -1) throw new Error('No separator character for ' + str);
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
95			if (split === 0) throw new Error('Missing prefix for ' + str);
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
96
97			var prefix = str.slice(0, split);
98			var wordChars = str.slice(split + 1);
99			if (wordChars.length < 6) throw new Error('Data too short');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
100
101			var chk = prefixChk(prefix);
102			var words = [];
103			for (var i = 0; i < wordChars.length; ++i) {
104			var c = wordChars.charAt(i);
105			var v = ALPHABET_MAP[c];
106			if (v === undefined) throw new Error('Unknown character ' + c);
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
107			chk = polymodStep(chk).xor(new BigInteger('' + v));
108			// not in the checksum?
109			if (i + CSLEN >= wordChars.length) continue;
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
110			words.push(v);
111			}
112
113			if (chk.toString(10) !== '1') throw new Error('Invalid checksum for ' + str);
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
114			return { prefix: prefix, words: words };
115			}
116
117			function convert(data, inBits, outBits, pad) {
118			var value = 0;
119			var bits = 0;
120			var maxV = (1 << outBits) - 1;
121
122			var result = [];
123			for (var i = 0; i < data.length; ++i) {
124			value = value << inBits \| data[i];
125			bits += inBits;
126
127			while (bits >= outBits) {
128			bits -= outBits;
129			result.push(value >>> bits & maxV);
130			}
131			}
132
133			if (pad) {
134			if (bits > 0) {
135			result.push(value << outBits - bits & maxV);
136			}
137			} else {
138			if (bits >= inBits) throw new Error('Excess padding');
			0 ignored issues – show Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
139			if (value << outBits - bits & maxV) throw new Error('Non-zero padding');
			0 ignored issues – show introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report You have used a bitwise operator `&` in a condition. Did you maybe want to use the logical operator `&&` Loading history... Coding Style Best Practice introduced 2018-01-03 13:31 UTC by Report Bug Copy Issue Report Curly braces around statements make for more readable code and help prevent bugs when you add further statements. Consider adding curly braces around all statements when they are executed conditionally. This is optional if there is only one statement, but leaving them out can lead to unexpected behaviour if another statement is added later. Consider: if (a > 0) b = 42; If you or someone else later decides to put another statement in, only the first statement will be executed. if (a > 0) console.log("a > 0"); b = 42; In this case the statement `b = 42` will always be executed, while the logging statement will be executed conditionally. if (a > 0) { console.log("a > 0"); b = 42; } ensures that the proper code will be executed conditionally no matter how many statements are added or removed. Loading history...
140			}
141
142			return result;
143			}
144
145			function toWords(bytes) {
146			return convert(bytes, 8, 5, true);
147			}
148
149			function fromWords(words) {
150			return convert(words, 5, 8, false);
151			}
152
153			module.exports = { decode: decode, encode: encode, toWords: toWords, fromWords: fromWords };

btccom / cashaddress-js

Pull Request — master (#1)

index.js ➔ decode C

Complexity

Size

Duplication

Importance

How to fix Complexity

Complexity

Duplication Side-by-Side

Filter issues like