RequireEachLineMatches is an AssertionFunc that treats each line of expected string as a regex that must match the actual string.

RequireStrippedStringsEqual is an AssertionFunc that does a simple string comparison of expected and actual after normalizing whitespace.

CommandResultsChecker tests a command-wrapped function by running it with predefined inputs and comparing the outputs to expected results.

ProcessorResultsChecker tests a processor function by running it with predefined inputs and comparing the outputs to expected results.