Module main file name remains in cache, causing issues when main file is changed in newer versions

[julianduque]

Re-opening this issue here by @indutny request
Related: nodejs/node-v0.x-archive#8266
Reproduction case: https://gist.github.com/sbellone/3947632a42be73553abb

Module._pathCache and var packageMainCache do not play well when you switch between different versions of the same module. I suggest that the version (or the compressed package-url) should be included in the cache key

[akhoury]

+1
have you tested this on Node 5+

[cjihrig]

What exactly is the expected output of the linked reproduction script? With node 0.10.40 and npm 1.4.28, I get a crash "cannot find module async." However, with latest master and npm 3.3.12, the script runs to completion and prints winston version 0.6.2 and 0.7.2.

[akhoury]

I get a crash "cannot find module async."

which is exactly the problem. quoting the description of the test-case gist

It will fail because 'winston' 0.6.x uses 'async' 0.1 whereas 'winston' 0.7.x uses 'async' 0.2, which has changed its main file. Since the main file name is kept in cache in the variable packageMainCache (in module.js),

However,

with latest master and npm 3.3.12, the script runs to completion and prints winston version 0.6.2 and 0.7.2.

Which means it was fixed! yey!

[MylesBorins]

this may need to be patched on v4.x

/cc @jasnell

[jasnell]

Is this still an issue?

[akhoury]

nope