[BUG] Cannot find module 'ts-node' from 'parser.js'

[KalinaMatysiak]

Describe the bug
During the run test in jest, I get an error "Cannot find module 'ts-node' from 'parser.js'". I figure out the problem disappears when I commented on these lines in parser.js file.

It appears, that:

1. the require.extensions is deprecated
2. the require.extensions object has only the following keys: .js, .json, .node. It doesn't have the .ts key

Tests and src codebase is in typescript, including config files.

Expected behavior
A clear and concise description of what you expected to happen.

Please tell us about your environment:

• node-config version: 3.3.6
• node-version: 16.16.0
• ts-node version: 10.9.1

Other information

[markstos]

Other people are not reporting this problem outside of Jest, so it's not clear it's a node-config bug.

Yes, require.extensions is deprecated, but no one has proposed a better solution here.

There seem to be competing ways of loading TypeScript files. Some more related discussion is here: #530

Considering there's been no activity here since last October, it seems the issue may be isolated to how Jest is loading node-config and not a general problem, so I'm closing this.

A PR to improve the situation is still welcome.