Emacs hangs, at times, when using spread operator

[paxperscientiam]

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There is an issue with the spread operator as it pertains to emacs.

Emacs hangs in the context depicted when entering a spread operator. I think it may freeze after typing the first dot.

This might be specific to emacs, but here is the error message spit out into the minibuffer:

"Request failed: ((error http 400) . TypeError: Cannot read property 'start' of undefined)"

Thoughts?

EDIT: Things hung twice. First, when I tried to use the spread operator preceding "alertsUrl". After restarting, it hung again after trying to enter the second depicted spread operator. Thanks

Originally posted here: https://github.com/ternjs/tern/issues/999#issuecomment-480630278