feat add BigNumber tests

This commit is contained in:
nanov 2019-11-07 10:27:20 +02:00
parent eafe2f9f55
commit 0efc46b014
2 changed files with 48 additions and 66 deletions

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@ -1,66 +0,0 @@
'use strict';
const { jsbn: { BigInteger } } = require('node-forge');
class BigNumber {
constructor(value, radix = 10) {
if (value === null || value === undefined)
throw new Error('value is missing.');
this._n = new BigInteger(null);
if (value instanceof BigNumber)
this._n = value._n;
else if (value instanceof BigInteger)
this._n = value;
else if (typeof value === 'number')
this._n.fromInt(value);
else if (typeof value === 'string')
this._n.fromString(value, radix);
else if (Buffer.isBuffer(value))
this._n.fromString(value.toString('hex'), 16);
else if (Array.isArray(value))
this._n.fromString(Buffer.from(value).toString('hex'), 16);
else
throw new TypeError('Unsupported value type.');
}
toBEBuffer(length = undefined) {
const arr = this._n.toByteArray();
if (length && arr.length > length)
throw new Error('Number out of range.');
while (arr.length < length)
arr.unshift(0);
return Buffer.from(arr);
}
toBuffer() {
return Buffer.from(this._n.toByteArray());
}
toString(radix = 10) {
return this._n.toString(radix);
}
and(num) {
return new BigNumber(this._n.and(new BigNumber(num)._n));
}
mul(num) {
return new BigNumber(this._n.multiply(new BigNumber(num)._n));
}
mod(num) {
return new BigNumber(this._n.mod(new BigNumber(num)._n));
}
shrn(num) {
return new BigNumber(this._n.shiftRight(new BigNumber(num)._n));
}
static fromBuffer(buf) {
return new BigNumber(buf.toString('hex'), 16);
}
}
module.exports = BigNumber;

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test/unit/BigNumber.js Normal file
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'use strict';
/* eslint-env node, mocha */
const { assert } = require('chai');
const { jsbn: { BigInteger } } = require('node-forge');
const BigNumber = require('../../lib/crypto/BigNumber');
const types = [
{ name: 'BigNumber', value: new BigNumber(11) },
{ name: 'BigInteger', value: new BigInteger('11') },
{ name: 'string with default radix', value: '11' },
{ name: 'string with radix 16', value: '0b', radix: 16 },
{ name: 'Buffer', value: Buffer.from('0b', 'hex') },
{ name: 'Array', value: [11] },
];
describe('BigNumber', () => {
describe('creating an instance', () => {
it('should throw with no value given', () => assert.throws(() => new BigNumber()));
it('should throw wrong value type', () => assert.throws(() => new BigNumber({})));
for (const { name, value, radix } of types) {
let instance;
describe(`out of ${name}`, () => {
it('create instance', () => assert.doesNotThrow(() => {
instance = new BigNumber(value, radix);
}));
it('toString with radix 10', () => assert.equal(instance.toString(), '11'));
it('toString with radix 16', () => assert.equal(instance.toString(16), '0b'));
it('toBuffer', () => assert.equal(instance.toBuffer().toString('hex'), '0b'));
it('toBEBuffer without length', () => assert.equal(instance.toBEBuffer().toString('hex'), '0b'));
it('toBEBuffer with length', () => assert.equal(instance.toBEBuffer(4).toString('hex'), '0000000b'));
});
}
});
describe('exports', () => {
it('toBEBuffer with too short length should throw', () => assert.throw(() => new BigNumber(837462187362).toBEBuffer(1)));
});
describe('operators', () => {
const num = new BigNumber(1);
it('and', () => assert.equal(num.and(1), 1));
it('mul', () => assert.equal(num.mul(2), 2));
it('mod', () => assert.equal(num.mod(1), 0));
it('shrn', () => assert.equal(num.shrn(1), 0));
});
});