Do similar tasks exist that would apply more generally to picking up any programming language? Working on non-trivial projects seems to be a great way of learning new languages and tools, and I wonder if there are a set of projects that would touch on a decent chunk of a what is offered by a typical language.

Then again, every language has its strengths and weaknesses so perhaps such projects do not exist?

I like to implement a Conway Life engine for this purpose. Small self-contained problem that requires UI, timing loops / iteration, and graphics.

It's also embarrassingly parallelizable if your language supports parallelization primitives you want to exercise.

Games are a fun way of trying out a new toolset. I've implemented a few sudokus now.

Minesweeper is always fun!

Just curious, how did you nail it down to that specific issue and patch? That seems like a great skill to have.

With git, the command git bisect provides a mechanism for using binary search on a range of commits.