[eslint] Clean up eslint and babel-eslint

[fkling]

The eslint setup in astexplorer is a bit chaotic. I'm not sure if it's worth investing a lot of time to clean this up in the light of #197 (which I will hopefully finish some day 😛 ), so I just did some minimal changes:

• Switch the default parser for eslint2 and eslint3 to babel-eslint, because that's what eslintUtils uses.
• Enable sourceType: 'module' in eslintUtils.
• Make the babel-eslint parser actually refer to babel-eslint and not acorn-to-esprima.
• Since acorn-to-esprima is deprecated, hide in from the menu.

In order to really clean this up, eslint1 would have to use an older version of babel-eslint that uses acorn-to-esprima, but I didn't want to spend more time with this.

@hzoo , does this look good?

cc @kentcdodds (follow up to #219 )

[hzoo]

I think it'd be ok to drop eslint1 anyway since there's an v4 coming out? Sounds fine

[kentcdodds]

Honestly I don't see much reason to keep anything but the latest version 🤷‍♂️

[fkling]

@kentcdodds Are you saying all my efforts in #197 are for nothing? 😛 jk

Honestly I don't see much reason to keep anything but the latest version

One reason is to be able to load snippets that were created with an older version of a tool or parser.

I think it'd be ok to drop eslint1 anyway since there's an v4 coming out?

I thought the same, however, google analytics says that there is still traffic for eslint1 (last 30 days):

And I believe these are really instances where eslint1 is selected, not just loaded for an existing snippet (but I have to check the code for that 😉 ).

However, in general I think we should only expose the latest version of a tool, but make it still loadable if needed, just like in this case for acorn-to-esprima. We kind of get that with #197 anyway.

[fkling]

so, good to go? 😃