Version 1.3.1 of mk-project.el is available from github or the Emacs Wiki. David Findlay reported that project-grep and project-ack where running from the project basedir's parent directory, not the project basedir. This behavior was possible on certain versions of Emacs if the project's basedir didn't include a trailing slash -- like this:

(project-def "test-project"
  ((basedir "/home/me/test-project") ; no trailing slash
   ...
   ))

The new version ensures that the trailing slash is appended to basedir when it is used as the default-directory value.

Thanks much to David for the bug report and helping me test potential solutions!

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