In #1251, we now have a proper whitelist of all the types that should have parenthesis. Turns out, it included NullableTypeAnnotation which is `?a`. For `?a => void` this wasn't needed but for `(?(a => b)) => c` it was! It's better to always put it anyway if it's not just a simple literal.
I've added tests for all the combinations I could think of, so we'll catch regressions if they happen.
Fixes#1353
* Extract custom tests from tests/flow/
Approach:
1. Remove all .js files in tests/flow except .snap.js files.
2. Copy over all .js files from tests/ in the flow repo.
3. Go through the diff looking for deletions.
- It was easy to see which deletions were due to changes in the tests
due to updates in the flow repo.
- For the rest of the deletions, I used `git blame` to verify that
they had been added by us since the flow tests were copied over.
This makes tests/flow/ simply a copy of the tests from the flow repo,
making it easier to sync with the upstream flow tests in the future.
* Add a script for syncing the flow tests
* Sync the flow tests
Christopher Chedeau