metamask-extension/test/unit/migrations/026-test.js

const assert = require('assert')
const migration26 = require('../../../app/scripts/migrations/026')
const oldStorage = {
  'meta': {'version': 25},
  'data': {
    'PreferencesController': {},
    'KeyringController': {
      'walletNicknames': {
        '0x1e77e2': 'Test Account 1',
        '0x7e57e2': 'Test Account 2',
      },
    },
  },
}

describe('migration #26', () => {
  it('should move the identities from KeyringController', (done) => {
    migration26.migrate(oldStorage)
      .then((newStorage) => {
        const identities = newStorage.data.PreferencesController.identities
        assert.deepEqual(identities, {
          '0x1e77e2': {name: 'Test Account 1', address: '0x1e77e2'},
          '0x7e57e2': {name: 'Test Account 2', address: '0x7e57e2'},
        })
        assert.strictEqual(newStorage.data.KeyringController.walletNicknames, undefined)
        done()
      })
      .catch(done)
  })

  it('should successfully migrate first time state', (done) => {
    migration26.migrate({
      meta: {},
      data: require('../../../app/scripts/first-time-state'),
    })
      .then((migratedData) => {
        assert.equal(migratedData.meta.version, migration26.version)
        done()
      }).catch(done)
  })
})