Add open on ENTER behavior

[jasonchangxo]

Note: This is my second time contributing to open source so please let me know if there's anything I can fix/change/edit with this PR.

I was working on accessibility/screen reader related issues which requires a lot navigating via keyboard-only. I found that pressing ENTER on the combobox does not open the options, which I believe to be standard expected behavior with dropdowns and comboboxes.

[coveralls]

Coverage decreased (-0.3%) to 92.056% when pulling 56e5048 on jasonchangxo:open-on-enter into 7523c20 on JedWatson:master.

[JedWatson]

Thanks @jasonchangxo

The PR itself looks good but I've checked the behaviour of HTML <select> controls in the browser, and enter doesn't actually open / close the menu (I believe it would submit the form if the control is inside one, and there is a type="submit" button... that's another story though)

Spacebar, however, does toggle the menu's open state; so I think it would be a good change to toggle react-select's open state when spacebar is pressed.

Note that we'd only toggle the menu closed when the select is not searchable - you'd need to use enter to select the focused option when the menu is open if the select is searchable.

I'm going to close this PR but please do open a new one with that change if you'd like to contribute it :)

[JedWatson]

Oh, forgot to mention - you can see the default behaviour by playing with this sandbox: https://codesandbox.io/s/1q14m9wxkj

[jasonchangxo]

Hi Jed, Thanks for making my first open source contributing experience very enjoyable! Contributing back to the community is actually quite fun and I expect to do more in the future. As for this PR, I've gone ahead and made the necessary changes in a new PR to align with the browser's <select> behavior on spacebar keypress. Feel free to let me know if I need to make edits. :)

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-Jason

On Wed, Oct 18, 2017 at 8:49 PM, Jed Watson ***@***.***> wrote: Oh, forgot to mention - you can see the default behaviour by playing with this sandbox: https://codesandbox.io/s/1q14m9wxkj — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#2037 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AeNHi4TPWU4IQuV9KIsOwL706xEoUm7bks5stsbWgaJpZM4PuR2Q> .

-- *Jason Chang* Software Engineer *t.* 408.933.8050 <(925)%20339-7051> *e.* jason.chang@crossoverhealth.com <lindsay.brecht@crossoverhealth.com> *w. *crossoverhealth.com