WP scripts plugin-zip missing root-level files

Using the @wordpress/scripts package, when I run the wp-scripts plugin-zip command it generates a zip file with the /build directory (and any other directories specified in "files": []). But it misses all files at the root level (README, plugin entry point, etc.) even when specifically providing the file name in package.json files.

I don’t receive any error messages — in fact the messaging in the console suggests it’s working. When I run the script I see the following in the console:

> wp-scripts plugin-zip

Creating archive for <code>@washingtonstateuniversity/hrswp-employee-recognition</code> plugin... 🎁

Using Plugin Handbook best practices to discover files:

  Adding <code>CHANGELOG.md</code>.
  Adding <code>LICENSE.md</code>.
  Adding <code>README.md</code>.
  Adding <code>build/index.asset.php</code>.
  Adding <code>build/index.css</code>.
  Adding <code>build/index.js</code>.
  Adding <code>build/style-index.css</code>.
  Adding <code>build/blocks/er-award-description/block.json</code>.
  Adding <code>build/blocks/er-award-meta-year/block.json</code>.

Done. <code>@washingtonstateuniversity/hrswp-employee-recognition.zip</code> is ready! 🎉

But all I see in the generated zip file is the build directory. It misses the entrypoint entirely and, although it says “Adding LICENSE.md”, etc., those root-level files are not in the zip.

There appear to be two issues here:

1. The plugin-zip.js script doesn’t check for namespaces on the plugin name, and passing @namespace\plugin-name to zip.addLocalFile() seems to fail silently. The can be circumvented easily enough using "files": [], but is unexpected per the documentation.
2. The plugin-zip.js script zip.addLocalFile( file, dirname( file ) ); appears to fail when dirname( file ) is '.'.

If I replace the existing:

zip.addLocalFile( file, dirname( file ) );

with:

if ( '.' !== dirname( file ) ) {
    zip.addLocalFile( file, dirname( file ) );
} else {
    zip.addLocalFile( file );
}

Then it appears to run as expected. That said, I don’t know if there is something wrong with my environment or my use of wp-scripts, as I haven’t been able to find anyone else with this problem.

My environment:
– @wordpress/scrips v22.5.0
– Node.js v16.14.2, npm v8.5.0 (same behavior seen with Node 14 and npm 6)
– WSL 2 on Windows 10