BuildMain builds the main package in the current working directory.

ContextMain gets a test context from a TestMain function.

EndToEndTest gets the test context, and sets the test as Parallel.

Retry runs function f for up to maxAttempts times until f returns successfully, and reports whether f was run successfully.

SystemTest gets the test context.

R is passed to each run of a flaky test run, manages state and accumulates log statements.

Runner holds the result of `go build`.