Function is

is(test: string, expect: string, message?: string): void
Expect the test string to be identical to the expected string.
Parameters
- test: string
  A test that returns a string result
- expect: string
  The expected string to use for comparison
- message: string = ...
  The exception message to show if an unexpected result was found. If not set, will display a default message for this type of test.
Returns void