Interview Q&A / Git & GitHub

1. Why is the submodule folder empty after cloning, and how do you fix it?

   A normal clone does not download submodule contents. Run git submodule update --init --recursive, or clone with git clone --recurse-submodules next time.

   BeginnerQuick answer1 min read
2. How do you update a submodule to its latest version?

   Go into the submodule, pull the wanted commit, then commit the changed pointer in the parent. Or run git submodule update --remote to fetch the tracked branch's latest commit for you.

   IntermediateQuick answer1 min read
3. What is a Git submodule?

   A submodule lets one repository contain another repository at a fixed commit. The parent stores only the URL and the exact commit hash, so the child's history stays separate.

   IntermediateQuick answer1 min read
4. Why is a submodule in detached HEAD state, and is that a problem?

   The parent pins an exact commit, so Git checks the submodule out at that commit, not on a branch. It is normal. To edit the submodule, check out a branch inside it first, or commits can get lost.

   IntermediateQuick answer1 min read
5. How do you remove a submodule properly?

   Run git submodule deinit -f path, then git rm -f path, and delete the leftover .git/modules/path folder. Commit the change. Just deleting the folder leaves stale configuration behind.

   AdvancedQuick answer1 min read