The Strange Case of Dr. Linux and Mr. Mac

Few days back, some of the tests started failing on CI server. When I tried to run the tests locally, they were passing.

After debugging for a while, I found that the tests were failing because of the case sensitivity of the file system. One of the developer was using Linux and had committed 2 files with the same name but different case(config.json, Config.json).

Linux file system is case-sensitive. So these 2 files will be shown as 2 different files.

But Mac/Windows file system is case-insensitive. Out of these 2 files, only one file will be shown.

Due to this, the tests were failing on Linux but passing on Mac. Once the case of the file was corrected, the tests started passing on both the systems.

I have been using Mac for a long time and never faced this issue. Even though Mac's APFS is case-insensitive, we can create a case-sensitive volume using Disk Utility.

We have to be aware of these differences when working on a project with developers using different OS.