index.test.js

const { Application } = require('probot')
// Requiring our app implementation
const myProbotApp = require('./')

const installationCreatedPayload = require('./test/payload/issues.opened.json')

describe('My Probot app', () => {
  let app, github

  beforeEach(() => {
    app = new Application()
    // Initialize the app based on the code from index.js
    app.load(myProbotApp)
    // This is an easy way to mock out the GitHub API
    github = {
      issues: {
        createLabel: jest.fn().mockReturnValue(Promise.resolve({}))
      }
    }
    // Passes the mocked out GitHub API into out app instance
    app.auth = () => Promise.resolve(github)
  })

  test.skip('creates a comment when an issue is opened', async () => {
    // Simulates delivery of an issues.opened webhook
    await app.receive({
      event: 'installation.created',
      payload: installationCreatedPayload
    })

    // This test passes if the code in your index.js file calls `context.github.issues.createComment`
    expect(github.issues.createLabel).toHaveBeenCalled()
  })
})

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