tests: replace jest with mocha

[connorjclark]

Fixes #14047

[connorjclark]

The glob / test filter is not working on Windows (0 tests running), gotta look into that.

[paulirish]

The debugging workflow needs some love. […]

re: debugging

I've had no issues with debugging, but that's because my new workflow is using vscode's JS Debugger terminal. Give that a shot. It auto attaches to child processes. Is there perhaps a flag to auto attach sub processes when calling node directly?

mkay i'll use the new fancy thing instead.

[paulirish]

what about a .mocharc.js file?

is going full CLI flag just easier given the permutations?

[connorjclark]

That file just extracts what you'd pass on the CLI to a file. It doesn't do what jest was doing, which was setting up its own environment for just those particular tests. That's the entire thing run-mocha-tests.js is doing. so in short:

is going full CLI flag just easier given the permutations?

Yeah

[connorjclark]

Windows is surely a dumb mistake in the process execution or paths or something, but I'm wasting way too much time trying to get a windows cloudtop to work at the office. I'll disable for now, and re-enable tomorrow when I'm back home with a windows machine to debug.

#14171