feat: add "skipHastePackages" option

[aleclarson]

Summary

The skipHastePackages option prevents reading of package.json files and keeps them out of the module map. It's important to fixing package deduplication in Metro (see here: facebook/metro#350), especially after symlink support is merged (see here: facebook/metro#257).

With support for symlinks in node_modules, it's very easy for the dependencies of one "locally developed" package to collide with another package's dependencies, which results in frustrating errors that are entirely avoidable.

Test plan

I tested it manually. Works great! I don't have time to get familiar with your test suite.

[SimenB]

This is another one for the FB people to review, sorry about that 😅

(it'll need a changelog entry, though)

[mjesun]

👍LGTM! We'll use this in Metro too. cc @rafeca (we recently discussed about it).

[cpojer]

@mjesun how were you thinking of using this in Metro? We depend on this behavior at FB. Did you mean to disable this by default for open source?

[rafeca]

@mjesun how were you thinking of using this in Metro? We depend on this behavior at FB. Did you mean to disable this by default for open source?

Some people using Metro internally at FB (but outside of RN) have run into similar issues due to global packages duplications (/cc @tjfryan ), allowing Metro to ignore haste packages would simplify their setups.

[aleclarson]

@cpojer This option is false by default, so it shouldn't affect FB internals. LGTM?

[cpojer]

Could you rebase this now that we are using TypeScript?

[SimenB]

I don't think the name skipHastePackages really says that it's just about package.json. Why not skipPackageJson or something?

[SimenB]

Missing changelog entry (and I think the name of the option is imprecise)

[aleclarson]

Good to go 👍

[cpojer]

Thank you.

[AmirBosch]

how do i use this flag ?

[github-actions]

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