Workaround for https://github.com/mafintosh/tar-stream/issues/64

gistfile1.txt

// In the code below, extract is a tar-stream extract object. 
// See https://github.com/mafintosh/tar-stream/blob/master/extract.js
//
// This 'entry' handler does not care about the contents of the entry,
// it just has to restructure the tar header data into a format that
// the caller understands. It then passes 'stream' to a PassThrough
// which discards the contents and allows tar-stream to move on to 
// the next entry.
//
// The problem with the initial pipe to PassThrough on line 35 is that
// with multi-megabyte files, 'stream' pauses because PassThrough seems
// to pause.
//
// The workaround code on lines 41-43 fixes this in my local tests.
//

extract.on('entry', function(header, stream, next) {
    var fileStat = tarReader._headerToFileStat(header);
    var relPath = header.name;
    tarReader.emit('entry', { relPath: relPath, fileStat: fileStat });
    stream.on('end', function() {
        if (header.type === "file") {
            tarReader.fileCount += 1;
        } else if (header.type === "directory") {
            tarReader.dirCount += 1;
        }
        next();
    });

    // The line below was the original call to pipe the tar stream
    // to a PassThrough reader. This stalled on multi-megabyte files.
    // It looks like tar-stream's internal writer paused because the
    // PassThrough stream paused.
    // 
    // stream.pipe(new PassThrough());

    // This works around https://github.com/mafintosh/tar-stream/issues/64
    // by explicitly unpausing the PassThrough stream. Not sure why it
    // only pauses once.
    // 
    let pt = new PassThrough();
    stream.pipe(pt);
    pt.resume();
});