Uncaught TypeError causing dozens of e2e test failures about openrefine HOT 4 CLOSED

This is likely caused by switching between different branches which did or did not include the change to package classes as .jar files instead of bare .class files. Sadly running ./refine clean does not clean up any .class files left over (because the new configuration does not produce them there, so mvn doesn't see it as needing cleaning up).
Assuming you don't have any important untracked files in your clone, you could run git clean -fdx to remove them all, and run OpenRefine again, which should hopefully solve the problem.

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You also may just need to refresh your server build. The errors are coming from something added relatively recently which requires support on the backend.

The end to end tests are run on every PR, so they are unlikely to be broken without anyone noticing.

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Thanks @wetneb and @tfmorris. Running git clean -fdx fixed it. I thought I was going crazy. I kept pulling from the upstream master branch and running ./refine clean.

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Another neat git command that I particularly use and can help (depending on if you are OK to delete untracked files) is git reset --hard @{u} which helps HEAD get back to a previous state quickly. Besides --hard there's other modes, like default --mixed, depending on what you need. But if you want to blow away changes and reset the branch to match upstream @{u} then it's a great way.

--hard
Resets the index and working tree. Any changes to tracked files in the working tree since are discarded. Any untracked files or directories in the way of writing any tracked files are simply deleted.
https://git-scm.com/docs/git-reset#Documentation/git-reset.txt---hard

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