oh-my-git/levels/low-level/symref-no-deref

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[description]
When you have a symbolic ref (a ref pointing at another ref), and you decide you want it to be a regular ref again (pointing to an object), you're in for some trouble! :)
What happens when you try pointing the symbolic ref directly to the blob using `git update-ref`?
Oops! Turns out that when you reference a symbolic ref, it acts as if you had specified the ref it points to. To de-symbolic-ize it, use the `--no-deref` option directly after `update-ref`!
Weird, huh?
[congrats]
Whew, we've covered a lot of things: Blobs! The index! Trees! Commits! Refs!
You now know about almost everything about how Git repositories look like on the inside! We think that's pretty cool! :)
Everything else is just convention and high-level commands that make interacting with the objects more convenient.
We haven't covered:
- tag objects (they are the fourth object type - a bit like refs with a description and an author)
- configuration (allows you to specify remote repositories, for example)
- working with local files (which is, uh, arguably pretty important :P)
Thanks for playing! You're welcome to check out the "puzzle" levels in the dropdown, some of them are more advanced!
[setup]
BLOB1=$(echo delicious | git hash-object -w --stdin)
BLOB2=$(echo very | git hash-object -w --stdin)
git update-ref refs/curly "$BLOB1"
git symbolic-ref refs/fries refs/curly
[setup goal]
BLOB1=$(echo delicious | git hash-object -w --stdin)
BLOB2=$(echo very | git hash-object -w --stdin)
git update-ref refs/curly "$BLOB1"
git symbolic-ref refs/fries refs/curly
git update-ref --no-deref refs/fries "$BLOB2"
[win]
git symbolic-ref refs/fries && return 1
test "$(git show-ref -s refs/fries)" = "035e2968dafeea08e46e8fe6743cb8123e8b9aa6"