index.test.js

const fs = require('fs').promises

const Config = require('./index')

let jsonDefaults = {
  setting:"defaultvalue",
  another: {
    setting:"avalue"
  }
}

let jsonLocals = {
  setting:"localvalue",
  another: {
    more:"stuff"
  },
  even: {
    deeper: {
      key: 'sodeep'
    }
  }
}

describe('config', function() {

  it('should only have values from config.defaults.json', async function() {
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    let config = new Config()
    await fs.unlink('config.defaults.json')

    expect(config.setting).toBe('defaultvalue')
    expect(config.another.setting).toBe('avalue')
  })

  it('should only have values from config.json', async function() {
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))
    let config = new Config()
    await fs.unlink('config.json')

    expect(config.setting).toBe('localvalue')
    expect(config.another.more).toBe('stuff')
  })

  it('should have both values with preference to config.json', async function() {
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))
    let config = new Config()
    await fs.unlink('config.json')
    await fs.unlink('config.defaults.json')

    expect(config.setting).toBe('localvalue')
    expect(config.another.more).toBe('stuff')
    expect(config.another.setting).toBe('avalue')
  })

  it('should respect a given basepath', async function() {
    await fs.mkdir('tmp')
    await fs.writeFile('tmp/config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('tmp/config.json', JSON.stringify(jsonLocals))
    let config = new Config('tmp')
    await fs.unlink('tmp/config.json')
    await fs.unlink('tmp/config.defaults.json')
    await fs.rmdir('tmp')

    expect(config.setting).toBe('localvalue')
    expect(config.another.more).toBe('stuff')
    expect(config.another.setting).toBe('avalue')
  })

  it('should have all values with preference to env', async function() {
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))
    
    process.env['SETTING'] = 'overwritten-by-env'
    process.env['ANOTHER_MORE'] = 'false'
    process.env['EVEN_DEEPER_KEY'] = 'true'
    
    let config = new Config()

    await fs.unlink('config.json')
    await fs.unlink('config.defaults.json')

    delete process.env['SETTING']
    delete process.env['ANOTHER_MORE']
    delete process.env['EVEN_DEEPER_KEY']

    expect(config.setting).toBe('overwritten-by-env')
    expect(config.another.more).toBe(false)
    expect(config.even.deeper.key).toBe(true)
    expect(config.another.setting).toBe('avalue')
  })

  it('should read in a file when given', async function() {
    jsonLocals.setting = 'file:file.txt'
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))
    await fs.writeFile('file.txt', 'value-from-file')

    let config = new Config()

    await fs.unlink('config.json')
    await fs.unlink('config.defaults.json')
    await fs.unlink('file.txt')
    jsonLocals.setting = 'localvalue'

    expect(config.setting).toBe('value-from-file')
  })
  it('should show a message and keep the setting when file given but not found', async function() {
    jsonLocals.setting = 'file:file.txt'
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))

    let config = new Config()

    await fs.unlink('config.json')
    await fs.unlink('config.defaults.json')
    jsonLocals.setting = 'localvalue'

    expect(config.setting).toBe('file:file.txt')
  })

  it('should reload if asked', async function() {
    await fs.writeFile('config.defaults.json', JSON.stringify(jsonDefaults))
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))

    let config = new Config()

    expect(config.setting).toBe('localvalue')

    jsonLocals.setting = 'reloaded-value'
    await fs.writeFile('config.json', JSON.stringify(jsonLocals))

    config.reload()

    await fs.unlink('config.json')
    await fs.unlink('config.defaults.json')
    jsonLocals.setting = 'localvalue'

    expect(config.setting).toBe('reloaded-value')
  })
})