pubsub.subscribe throws an error when trying to use it promise-way

[negamaxi]

• Version: 0.27.0
• Platform: Linux
• Subsystem: x64

Type: Bug

Severity: High

Description: pubsub.subscribe throws an error when trying to use it promise-way. Seems to be related with #1129.

Steps to reproduce the error:

await ipfs.pubsub.subscribe(topic, handleMessage)
// Uncaught TypeError: callback is not a function

Therefore callback-way is the only available for now. Here is simple workaround:

  await new Promise((resolve, reject) => {
    ipfs.pubsub.subscribe(topic, handleMessage, err => {
      if (err) {
        reject(err)
      } else {
        resolve(err)
      }
    })
  })