fix: replace intlshape intersection type with spread

[meandmax]

Hello Flow Typed Team,

this change removes a bug which we experienced with IntlShape. In our case, everything except the first of type in the intersection $npm$ReactIntl$IntlConfig was missing when we did a spread of the property. This makes me believe that $npm$ReactIntl$IntlConfig is treated exact in our code base, even though it is not declared as exact.

We do not experience the bug in https://flow.org/try/ unless we make the first type of the intersection $npm$ReactIntl$IntlShape exact as you can see below:

example

The solution for us is using spreading instead.

• Type of contribution: fix

Other notes:

@jbrown215 is the change to make most of the types inexact intentional?

Thank you very much!
Cheers Max

[jbrown215]

is the change to make most of the types inexact intentional?

Not sure which change you are referring to, but generally: intersections are only meaningful on inexact object types. Most intersections with exact object types are cannot be inhabited by a value, since an object can't have exactly one set of properties and exactly a different set of properties.

Maintianers: FWIW, this change looks good to me. If possible, $npm$ReactIntl$IntlConfig and $npm$ReactIntl$IntlFormat should be made exact so that $Exact isn't necessary

[pascalduez]

@meandmax Thanks for the PR!
Would it be possible that you also add a test replicating your issue/use-case? So that next changes or refactor doesn't unintentionally revert this behaviour.

[meandmax]

Howdy @pascalduez,

I'm more than happy to add a test. Unfortunately, this error does only appear in the repl if I make $npm$ReactIntl$IntlConfig explicitly exact.

In our project, it appears to me that for some reason $npm$ReactIntl$IntlConfig is treated exact (even though it is declared as inexact) and as a result, the intersection type which is replaced in this PR does not work correctly specifically if we try to spread properties.

I'm unsure how should I test it. I added some tests checking exactness and if it is happy with spreading, but I might need some help.

Thank you,
Cheers Max

[meandmax]

@jbrown215 under which circumstances does a type which is declared as inexact behave like an exact type, because this seems to be the case in our project.

Thanks for your help :)

[pascalduez]

@meandmax Maybe you have a $Shape somewhere? It has that behaviour.
https://flow.org/try/#0PQKgBAAgZgNg9gdzCYAoVAXAngBwKZgBiccYAvGAN6phhwB2eAXGAM4YBOAlvQOYA0NMBgRwW9AK4BbAEZ4OggL7oYeDMLzsWAEgDKACwCG+ADzE4APnJU6jFgHJ7-Yfo55mYR2GVA