Pretty nice and funny kata of the series, hopefully I'll be able to solve more of them.

Looks like you like golf :D

very nice!!

It's 8, but I've seen where the problem is

"For level n" <-- this tiny bit..

For level n you must determine the formula by yourself using given examples from the table.

Your score array contains only up to level 7.

Cool kata, but one thing I can't get is how the random tests are suppose to work?

My solution passes all the basic tests, but random tests all return "Cannot read properties of undefined",

when I copy the input from the random test in VScode for example though it works fine and returns the score?

"The game starts at level 0. The level increases every ten lines you clear."

It's pretty self explanatory..

Terrible description. The process of moving to a new level is not described; I had to try all the options to find the right one. Wasted my time

I understand the logic, but why is the sorting behavior different between the two approaches (this code and mine)?

I interpreted it as: when you reach 30 lines, the game is finished. Which turned out to be the correct interpretation.
Not sure if the author is active, but I would enjoy solving the rest of the (intended) series.

This means 29 is the maximum field height instead. I would change the description:

The game ends if all commands from input were interpreted or the maximum field height (29 units) is exceeded.

This took my ages to discover. It's counter intuitive the maximum field height is an exclusive boundary.

The game ends if all commands from input were interpreted or the maximum field height (30 units) is reached.

impossible if you ask me, there no spec whatsoever how to clear lines

• one at a time
• can pieces drop down
• can individual cells drop down

ah crap, I read over this part: "When such a line is formed, it disappears and any blocks above it fall down to fill the space."

no, just for shortening code