repl: add experimental TypeScript support

[avivkeller]

Adds experimental TypeScript support to the REPL, opt-in-able via the --experimental-repl-typescript flag.

[nodejs-github-bot]

Review requested:

• @nodejs/config
• @nodejs/loaders

[marco-ippolito]

Why release candidate

[avivkeller]

The underlying transformer, https://nodejs.org/api/module.html#modulestriptypescripttypescode-options, is a release candidate, I figured this would be an extension of that

[marco-ippolito]

I think this has a larger scope than that api

[marco-ippolito]

Can you add a test for:
const foo = () => 'hello world'; foo<Object>();
If should return false. This basically makes sure valid js is evaluated before ts

[Renegade334]

This is going to cause problems with multiline, I suspect.

Concise example:

const regexps = new Set<
  RegExp
>();

If typed as multiline input to REPL, it's going to consider the statement complete after the second newline, as it's a valid JS statement, and evaluate new Set < RegExp, which evaluates to true. I don't know that there's any way around these sorts of parsing conflicts.

[marco-ippolito]

It should be handled exactly like we handle the -e and -p. If it's valid js treat it as such otherwise fallback on TS

[codecov]

Codecov Report

❌ Patch coverage is 68.00000% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.14%. Comparing base (4f844f4) to head (86bc763).

Files with missing lines	Patch %	Lines
lib/internal/repl/eval.js	65.21%	8 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #64077   +/-   ##
=======================================
  Coverage   90.13%   90.14%           
=======================================
  Files         741      741           
  Lines      241976   241998   +22     
  Branches    45543    45544    +1     
=======================================
+ Hits       218116   218140   +24     
+ Misses      15379    15378    -1     
+ Partials     8481     8480    -1     

Files with missing lines	Coverage Δ
src/node_options.cc	76.72% <100.00%> (+0.02%)	⬆️
src/node_options.h	98.01% <100.00%> (+<0.01%)	⬆️
lib/internal/repl/eval.js	90.55% <65.21%> (-2.62%)	⬇️

... and 35 files with indirect coverage changes

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