A handful of tests started failing due to syntax changes when switching over to Prettier to do JS formatting. It is likely this is because the tests try to do things like manually parse the stack with changed formatting, rather than being actual execution changes on the test (this has not been validated in every case). These tests should be fixed so that formatting changes in files do not cause them to fail. If they are fixed, they can be removed from the .prettierignore file so that they can have the same syntax as the rest of the javascript. These files got selected to be reverted because they were failing tests at the time of being added to the .prettierignore, its possible the failures were from a different bug existing at the time so every file in this list may not actually have test failures when removed from the list. To reproduce/check the failures, remove a file from the .prettierignore and run "bazel run format". You should see syntax changes in the files. See - https://github.com/10gen/mongo/pull/40675