Scalafix followups: Move doc specs to doc/jdoc package

[chbatey]

#26019 (review) introduced scalafix to remove unused imports. It is not enabled on compile and can remove imports that are included in specs for docs.

To followup:

• Ignore files in doc/jdoc package
• Move any doc specs to the doc for Scala and jdoc package so that imports are necessary e.g. FlowZipSpec is in the akka.stream.scaladsl and is used for docs. The unit test parts should remain but the docs part should be in a new file in the docs package do that imports from akka.stream.scaladsl are required
• Test how fast it is to enable on compile and decide if we want it enabled by default

[He-Pin]

I think Ignore files in doc/jdoc package is already done
Sorry, actually it not done yet: #26084

[dwijnand]

Why is the ignore files part necessary? Once they're out of their owning package aren't they safe to be kept clean by Scalafix?

[He-Pin]

best to defer after :#26043

[He-Pin]

without

[success] Total time: 439 s, completed 2018-12-10 3:45:26

with

[success] Total time: 643 s, completed 2018-12-10 5:25:08

@chbatey I think it slowed a lot.

[He-Pin]

another way to protect is

//#zip-with-index
import akka.stream.scaladsl.Source // scalafix:ok
//#zip-with-index

as @marcelocenerine mentioned at :scalacenter/scalafix#918

[raboof]

That would be possible, but easy to forget. Also, moving those tests to a separate package protects against forgetting imports or accidentally depending on non-public API's in documentation snippets. So it still seems worth doing.

Good to know though!