I too agree that implementing 'lset' / 'lget' was quite gnarly. I had to invent an algo mostly from whole cloth after getting some hints on Stack Overflow (I do see that @MikChan had a similar approach, so maybe it wasn't that original).

Fix compilation warnings.

Congratulations!
Well, actually it should not be that hard to transform bf from pointer version to named version if you just know exactly how many slots do the pointer version relay on
Anyway, glad that you had fun with bf

Wow! This was hard. Needed one week to finish it :D
It was hard to find the right brainfuck algorithms.

I used this esolangs.org to help me with it.
They had algorithms where there were var-names instead of pointer movements and other algos without names.
It was hard to find a solution that works for both.
I did lset, lget and cmp completly by myself, because I couldn't find any premade solution hahahaa :D

HODOR!!! WTF!!! Really cool artpiece ;)

    Assert::That(isSubsequence(string2, answer), Equals(true));
    Assert::That(isSubsequence(string1, answer), Equals(true));

I think that should have been

    Assert::That(isSubsequence(string2, actual), Equals(true));
    Assert::That(isSubsequence(string1, actual), Equals(true));

I changed that in the editor. Can you confirm I did that correctly?

OK, I've approved it. Thanks!

I don't know C++ worth a damn, so keep an eye out for comments regarding your translation. I very probably won't be able to solve any problems, so that's on you. :P

Okay I fixed that.
I have also noticed that my string-generator was wrong, it always generated the same string.
I fixed that too. It's my first translation between.

Yes that wrong. I will fix this. Thanks.

The random tests choose from 35 characters, not 36. You've forgotten 0. ( Also, you switched s and t. )

Could you fix that?

I see

    Assert::That(actual.length(), Equals(answer.length()));
    Assert::That(string1, Contains(actual));
    Assert::That(string2, Contains(actual));

in the random tests.

Does that mean you're checking for substrings and not subsequences? ( substrings are consecutive, subsequences need not be. )

Cool. I really like the "registers.get" function. Great idea!

I have the same problem. This is just weird.

This is a good way to solve this.