A diagnostic, as defined by the Diagnostic Design Guidelines:
An indication of a specific problem at a specific location within the source code being processed by a development tool.
Clients may not extend, implement or mix-in this class.
A list of messages that provide context for understanding the problem
being reported. The list will be empty if there are no such messages.
- correctionMessage → String
A description of how to fix the problem, or
nullif there is no such description.read-only
- hashCode → int
The hash code for this object. [...]
- problemMessage → DiagnosticMessage
A message describing what is wrong and why.
- runtimeType → Type
A representation of the runtime type of the object.
- severity → Severity
The severity associated with the diagnostic.