5.2.x breaks express.js route handling logic?

[nlfiedler]

The 5.1.0 version of pkg works fine for compiling and running our application, but the 5.2.1 (and maybe 5.2.0) changed in a way that the route handling in Express.js fails with a strange error.

::ffff:127.0.0.1 - - [24/May/2021:21:49:04 +0000] "GET / HTTP/1.1" 500 148
TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received type number (0)
    at validateString (internal/validators.js:124:11)
    at Object.resolve (path.js:1039:7)
    at Object.process.pkg.path.resolve (pkg/prelude/bootstrap.js:477:25)
    at View.lookup (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/view.js:114:32)
    at new View (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/view.js:94:20)
    at Function.render (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/application.js:570:12)
    at ServerResponse.render (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/response.js:1012:7)
    at /snapshot/helix-auth-svc-2021.1.0/lib/app.js:116:7
    at Layer.handle_error (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/router/layer.js:71:5)
    at trim_prefix (/snapshot/helix-auth-svc-2021.1.0/node_modules/express/lib/router/index.js:315:13)

The code in question is at https://github.com/perforce/helix-authentication-service although I doubt any of that is relevant.

Let me know what helpful information I can provide. I realize that what has been said so far is not much to go on.

[robertsLando]

@jesec ?

[jesec]

The only significant change in 5.2.x that may be related to this issue is the compression.

Other changes are just routine updates (bump Node.js versions, etc.) or macOS-only (codesigning, M1 support, etc.), which are quite unlikely to be related. #1173 is indeed a global functional change, but I don't think that's related.

The compression patch is quite large, and some elements in it can cause unintended behavioral change to no-compression use case, as we can see in #1189 .

@nlfiedler If possible, can you provide a minimum repository for reproduction of the issue?

cc: @erossignon

[jesec]

@nlfiedler I still need a minimum repo to reproduce. I can't reproduce it in my own Express.js project.

[erossignon]

@jesec, there was an issue in the compressed virtual file system that causes confusion for file that are dynamically accessed inside the /snapshot, as you spotted out. This is now fixed in #1200.
@nlfiedler I would be please to add a unit test if you describe a simple way to reproduce the behavior you found. so I can ensure that this PR fixes the issue. Alternatively, you could try to fetch #1200 and experiment on your side.

[dabenard]

@erossignon I am not related to @nlfiedler but I am facing what I believe to be the same issue in one of my projects.
You can find a repository containing minimal code to reproduce the issue here: https://github.com/dabenard/pkg-express.