title = Enter the time machine
cards = init commit-auto checkout

[description]

Another month later, you're woking on an essay about tardigrades!

But this time, a friend has borrowed you a time machine!

It's called "Git", and it's very shiny.

[setup]

rm -rf .git

echo "~ Why tardigrades are cool ~

- They can survive in space.
- They are resistant to extreme heat and cold." > essay.txt

[win]

# Initialize the time machine!
test -d .git

# Make a snapshot of your essay (a "commit")
test -d .git && git rev-parse HEAD

# Add another line to the essay.
test "$(cat essay.txt | wc -l)" -ge 5

# And make a second commit!
git rev-parse HEAD^ && test "$(git show HEAD:essay.txt | wc -l)" -ge 5

[congrats]

Nice! You can now travel between those two snapshots using `git checkout` - try it, and look at the essay in each commit!

You can also make some additional commits. When you feel comfortable, click on "Next Level".