I'm using Projectile to index a Rails 4 project. When I use M-x projectile-find-file to locate files using their file name, some files simply don't appear.
For example, I have a file located in app/controllers/api/v1/test_controller.rb, but typing M-x projectile-find-file entertest_controllerenter returns no results.
Is there a way to re-index the project, or figure out what's filtering out certain files?
The quick answer is to invalidate the projectile cache. When using projectile-find-file if you use C-u to send the universal argument before running the function, it will invalidate the cache before searching it. To match your example;
C-u M-x projectile-find-file
There are a number of other functions in projectile that use the prefix argument, check for any that call projectile-maybe-invalidate-cache if the universal argument is present.
More generally though, projectile provides projectile-invalidate-cache which is by default bound to C-c p i.