puppeteer example multiple file upload

JavaScript
  await page.waitForSelector('input[type="file"]')
  const files = await Promise.all([`${filePath}/travis_1.png`, `${filePath}/travis_2.png`])
  const input = await page.$('input[type="file"]')
  if (fileExists) {
    await input.uploadFile(...files)
  }
Source

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