File handle is never closed when zip file is unreadable

[Callisto82]

Consider the following code example when using the async API:

const zip = new StreamZip.async({file: 'unreadable.zip', storeEntries: true });
try {
  await zip.entries();
} finally {
  await zip.close();
}

When 'unreadable.zip' is not readable (e.g. a nearly empty text file), this code will leak a file handle to "unreadable.zip". This only happens with the promised-based API, not with the callback-based one.

The reason is found within the async close() method:

node-stream-zip/node_stream_zip.js

Line 748 in 7c5d503

async close() {

async close() {
  const zip = await this[propZip];
  ...
  zip.close();
}

The first line will already throw an exception if the zip file is completely unreadable. Therefore, zip.close() will never get called.