This is a tricky one to minimize... This happens when building an SBT (1.3.3, coursier 2.0.0-RC3-4, AFAICT) project via a gitlab-runner (12.4.1) on Windows 8 under the system (NT Authority\LocalSystem) or virtual (NT Service\gitlab-runner) account. Coursier attempts to store its cache in null/Coursier/v1 subfolder of the build folder, instead of AppData/Local for the corresponding account.
The account thing seems to be a red herring. The same thing seems to happen with a "vanilla" account. I've ran sbt in an empty project (with only a project folder), and it downloaded all the dependencies to the null folder.
Same thing started happening for me on Windows 10 on an ordinary user account (not system/virtual).
This was earlier reported in the SBT repository: https://github.com/sbt/sbt/issues/5206.
it looks like this is caused by some change in jre - sbt works correctly under 8u181 but fails to use proper cache folder using 8u231
just a note - this also affects current scalafmt and scalafix, which surprisingly don't use coursier provided by sbt, even if used from it
Most helpful comment
The account thing seems to be a red herring. The same thing seems to happen with a "vanilla" account. I've ran
sbtin an empty project (with only aprojectfolder), and it downloaded all the dependencies to thenullfolder.