Package-lock.json missing some deps compared to npm's version

[sebastienroux]

Issue description:

After converting yarn.lock, generated package-lock.json is missing some dep declaration and some "dev" flags (using 1.9.4)

Here all json/lock files : https://gofile.io/uploadFiles
Or directly attached (beware of .txt extension)
package-lock-npm.json.txt
package-lock-synp.json.txt
package.json.txt
yarn.lock.txt

I made a gitlab project for testing synp AND https://github.com/jeremylong/DependencyCheck.
https://gitlab.com/boloss/test-dependency-check
You can fork it if you want

[antongolub]

@sebastienroux

As I can see, we now have false-positive dev flags. It will take some time to clarify how the npm implements this logic.