I tried something similar at first, didn't think that way of skiping trough non-compliant, very clever to share the tentative number with the iterator

xD

I thought my solution will be the dodgyest. :D

OK guys, I have solved it. So, I can clarify, that the challenge requires you to reverse the object key-string. No mirrored characters needed.

Yes, by the description it expects a reverse of the string, but when I run a test, there it seems to expect reverse string with mirrored characters. Probably the description should be clarified.

Okay, I got it, thank you. I'll try to solve it other ways.

Hi. Your code timing out has nothing to do with this warning. It just means the tests should be updated to a newer version, but they still work fine.

I have solved the challenge with JavaScript.
My solution gets green at initial Test, but at Attempt it times out and advises "assertSimilar is deprecated, use assertDeepEquals".
I'm not sure, but maybe my solution times out because of the test's fault. Could someone confirm this, please?

Circumvent it.

Oh man! This one was challenging. It took me a week (and some Flector gel for my neck muscles), but I knew it, if I'll ever solve a 1 kyu kata, this one will be that, as Minesweeper was one of my favourite game back in win98 times and it doesn't need some twisted mind for solving it like for some other 1 kyu katas. I started to solve this challenge in a long and tiresome way, but as I went forward from the zero fileds to twos, threes and fours I gradually imporved my skills and came up with better and better, shorter ways. Then I realised, I could rewrite the beginning of my solution too, to make it shorter, and I could have reused some of my later applied functions, but it worked as it was, so I better left it as it was written at the first time. The whole code will be a memento of my improvement during the challenge. When I was at the final part, where only a few fields left unsolved I worried a bit because I have read here in the discussion that I can face performance issues, but luckily my solution went through the tests without any bigger problem. Sometimes it goes through all tests in 2,600ms. When I got more difficult random tasks, then even the 12,000ms wasn't enough though. I couldn't wait to see all green, but I can say, finally it worthed the effort and landed me in 2 kyu rank. The test results were a bit difficult to read sometimes because of the longer brown lines, but I liked the yellow-green-red evaluation. Thanks for the kata! Good job!

OK, it works! I didn't know I have to change the parsing engine at the top of the page with that button manually. Thank you.

Make sure you select the right Node's version in the selector. Also, backup your code, click reset and paste it again.

Thanks. I think Object.fromEntries() still doesn't work. So, I got frustrated and tried to flatten my two-D array with .flat(), but that doesn't work either.

Enabled v14, try again.