central issue for "default extensions"

This issue encompasses anything that deals with “what the default extensions are/should be”.

• #19 points out that .json is not included in the defaults.
• #137 points out that require.extensions is not used as the defaults
• https://github.com/substack/tape/issues/395 is related, but can be addressed with changes in tape, unrelated to whatever resolve does.
• (related but addressed: #150, #127, #90, #134)

There’s some PRs out that are hoping to change the defaults:

• #138 dynamically reads require.extensions on every call
• #145 replaces the default of .js with a hardcoded list of the default require.extensions value

I’m opening this so I can close the other issues, and so any further discussion can happen here.

Please try to read all of the previous discussions before commenting.

[ljharb]

I don’t refer to mjs as anything related to “michael jackson”, nor do i think it’s mocking in any way - if anything, it’s a reference to how people immediately think of him when they see “MJ” because he’s so prolific - so I think you’re looking a bit too hard for a reason to be upset.

[ljharb]

A file extension is strictly necessary, since Module and Script have distinct (and ambiguous) parsing goals, and a file extension is the proper and sole way to disambiguate textual parsing goals - so this result was inevitable once the choice of two parse goals was made in TC39 back in 2013 or so.