ruku, I'm not sure that your EAP build was your problem, but if you are like me and use a stable build and cannot update (compatibility issues with others in my project), I recommend a workaround by simply creating a new file and inserting the contents there file. It is not very elegant and requires manual refactoring for any files already mentioned in the project, but since you are moving the file to the project, you should not have this problem.
Like sday, this happened to me when moving a file inside a project. I do not use EAP Build. I am using 14.1.4, build # IC-141.15.32 build on June 18, 2015. I installed on 2015-09-05 from the JetBrains homepage mentioned in Sday. I am using osx 10.11.1.
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