In modern games, I think it’s fairly common to have a common 3d skeletons share names. So you can make animations like the one above apply to any character even if they have differences. It doesn’t mean that dog extends human, but it may mean that a dog model shares a lot of common “bones”, that are used for movement, with a human model.
So when a human animation is applied to the dog, you can see it warp to start position of the animation, move, and then then stop at the end position as a standing human, before warping back to idle animation (when it turns back into the dog shape)
Related, weapons in Destiny also share the same components across weapon types, and bugs have caused one weapon type to be used for another weapon, making funny things happen. Like how a hand canon (pistol) stretches like a bow because it’s model got used in place of the bow model at the start of this clip:
Code normally works fine after you write it and then hopefully at least test by hand. The new guy 5 years later, which do not fully grasp the extent of his actions, and the guy reviewing the code also not being too familiar with it, will not make sure everything does as intended.
Tests are correctness guarantees, and requires the code and/or the test to change to pass. They also explain how something should behave to people that don’t know. I work in a area where there are so many businesses rules that there is no one person that knows all of it, and capturing the rules as tests is a great way to make sure that rules remains true after someone else comes to change the code.