Does Evince support javascript in pdf files?

Essentially, it doesn't support it, so you can't turn it off.

[update 05.2018]: bug moved over to gitlab.

There is a bug report on this on bugzilla.
It is classified as Normal Enhancement.
Unfortunately I have no clue if they are actively working on it or not..

No, evince does not support Javascript.

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How to verify this?

To make it easier for others to verify the up-to-dateness of this answer, you can query two information sources:

1. There exists an official bug report (Support Javascript in PDF Documents) handling the feature request for Javascript, which - by now - does not mention a version for which the Javascript support is planned:

   Version: unspecified
[...]
Importance: Normal enhancement

2. Look at the official roadmap of evince, especially at the Javascript line from Roadmap#Unresourced: