[BUG] Sync list does not work

[movitto]

Listing of a tarball contents works in asynchronous mode, but when 'sync' is passed to tar.t, undefined is returned.

Fedora 33. nodejs v14.18.1. tar v1.32

The following works:

var entries = [];
await tar.t({
  file : 'mytarball.tgz',
  onentry : e => entries.push(e.header.path)
})
console.log(entries) # ['file1', 'file2', etc]

But the following does not work:

var entries = tar.t({
  file : 'mytarball.tgz',
  sync : true
})
console.log(entries) # undefined

Any insight as to why this is would be highly appreciated.

[isaacs]

It doesn't return a list of entries. You still have to give it an onentry method. It'll just call that method synchronously, rather than calling it at some point in the future.

var entries = [];
tar.t({
  file : 'mytarball.tgz',
  onentry : e => entries.push(e.header.path),
  sync: true,
})
console.log(entries) # ['file1', 'file2', etc]

Otherwise, it would potentially be storing a huge amount of data in memory. All the sync functions work exactly the same as the async ones, just sooner.