The mirror test is very flawed because it assumes other animals think ( or recognize ) like we do. We are mostly visual creatures so we create visual tests. But animals like cats are predominantly olfactory creatures. So if you planted smells of the cat, the cat would immediately recognize the smell as itself.

Imagine if cat psychologists created a test for humans. They would probably put your scent on one shirt and 9 other scents of other people on 9 different shirts and have you "recognize" yourself by picking out the shirt with your scent. Since we are visual creatures, we would fail such a test and the cat psychologists would claim that humans obviously have no self-aware. After all, how could a self-aware creature not recognize it's own scent.

That's how absurd the mirror test is. A mirror test for most animals would be like a smell test for humans. A cat might not recognize it's own reflection, but it will recognize its own scent. A human might not recognize our own scent, but we'll recognize our own reflection.