toString method
A string representation of this object.
Some classes have a default textual representation,
often paired with a static parse function (like int.parse).
These classes will provide the textual representation as
their string representation.
Other classes have no meaningful textual representation
that a program will care about.
Such classes will typically override toString to provide
useful information when inspecting the object,
mainly for debugging or logging.
Implementation
@override
String toString() =>
'DwUnpreparedServerCall: the code under test called '
'$operation($details), and the transport had no answer ready.\n'
'Prepare one by setting `$responder` on the transport before the code '
'runs — a read is never answered by default, because a test that does '
'not know what its subject fetches is the thing being caught here.';