https://github.com/ethworks/bn-chai
BN chai extends Chai with bn.js operations.
https://github.com/ethworks/bn-chai
Last synced: about 1 year ago
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BN chai extends Chai with bn.js operations.
- Host: GitHub
- URL: https://github.com/ethworks/bn-chai
- Owner: EthWorks
- License: mit
- Created: 2018-03-08T16:08:30.000Z (over 8 years ago)
- Default Branch: master
- Last Pushed: 2018-09-10T07:28:02.000Z (almost 8 years ago)
- Last Synced: 2025-04-09T02:46:28.035Z (about 1 year ago)
- Language: JavaScript
- Size: 10.7 KB
- Stars: 14
- Watchers: 4
- Forks: 5
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
# bn-chai
bn-chai extends [Chai](http://chaijs.com/) with assertions about [bn.js](https://github.com/indutny/bn.js/) decimals.
## Installation
```bash
npm install -s bn-chai
```
## Setup
```javascript
var chai = require('chai');
var expect = chai.expect;
var BN = require('bn.js');
var bnChai = require('bn-chai');
chai.use(bnChai(BN));
```
## Usage
When comparing two [bn.js](https://github.com/indutny/bn.js/) decimals **bn1** and **bn2**, instead of doing:
```javascript
expect(bn1.eq(bn2)).to.be.true;
```
You can do this instead:
```javascript
expect(bn1).to.eq.BN(bn2);
```
This plugin is also handy when comparing a [bn.js](https://github.com/indutny/bn.js/) decimal to an inline constant, so instead of writing:
```javascript
expect(bn1.eq(new BN('1'))).to.be.true;
```
You can simply write:
```javascript
expect(bn1).to.eq.BN(1);
```
Which is simpler and more readable.
## Assertions
### eq
Asserts that the target is **equal** to the given object.
```javascript
expect(new BN('1')).to.eq.BN(1);
expect(new BN('1')).not.to.eq.BN(0);
```
### lt
Asserts that the target is **less than** the given object.
```javascript
expect(new BN('0')).to.be.lt.BN(1);
expect(new BN('1')).not.to.be.lt.BN(1);
```
### lte
Asserts that the target is **less than** or **equal** to the given object.
```javascript
expect(new BN('0')).to.be.lte.BN(1);
expect(new BN('1')).to.be.lte.BN(1);
expect(new BN('2')).not.to.be.lte.BN(1);
```
### gt
Asserts that the target is **greater than** the given object.
```javascript
expect(new BN('1')).to.be.gt.BN(0);
expect(new BN('1')).not.to.be.gt.BN(1);
```
### gte
Asserts that the target is **greater than** or **equal** to the given object.
```javascript
expect(new BN('1')).to.be.gte.BN(0);
expect(new BN('1')).to.be.gte.BN(1);
expect(new BN('1')).not.to.be.gte.BN(2);
```
### negative
Asserts that the target is **negative**.
```javascript
expect(new BN('-1')).to.be.negative;
expect(new BN('1')).not.to.be.negative;
```
### even
Asserts that the target is **even**.
```javascript
expect(new BN('2')).to.be.even;
expect(new BN('1')).not.to.be.even;
```
### odd
Asserts that the target is **odd**.
```javascript
expect(new BN('1')).to.be.odd;
expect(new BN('2')).not.to.be.odd;
```
### zero
Asserts that the target is equal to 0.
```javascript
expect(new BN('0')).to.be.zero;
expect(new BN('1')).not.to.be.zero;
```
## Mixing BN, numbers and strings
You can mix BN with numbers and strings freely:
```javascript
expect(new BN('1')).to.eq.BN(new BN('1'));
expect(new BN('1')).to.eq.BN('1');
expect(new BN('1')).to.eq.BN(1);
expect('1').to.eq.BN(new BN('1'));
expect('1').to.eq.BN('1');
expect('1').to.eq.BN(1);
expect(1).to.eq.BN(new BN('1'));
expect(1).to.eq.BN('1');
expect(1).to.eq.BN(1);
```
## Executing example tests
Example unit tests making use of this plugin can be executed by running the following commands:
```
cd test
npm run test; npm run failTest
```