This patch:
- teaches test runner to understand custom argument spelling, e.g. `--file=evalu` and `-j10`
- fixes `--file` filter to actually focus file paths instead of focusing
all tests with given path
This ensures we get a proper error when something goes wrong. Should
also help with producing the right error code in the case of internal error.
Drive-by: fix location issue which manifests on the bots.
Drive-by: remove the use of Array.prototype.flat to make it work on bots.
This change introduces a TestWorker that can be in a certain state,
meaning it has run some beforeAll hooks of a certain test suite stack.
TestWorker can be created at any time, which allows for a number of features:
- don't run hooks for suites with no runnable tests;
- smarter test distribution (and possibility for variuos strategies);
- recovering from hook failures and test failure by creating a new worker;
- possible isolation between workers by running them in separate environments.
