whereValue method
Creates a WidgetSelector that finds all Semantics where value matches the condition.
Example usage:
spot<Semantics>().whereValue((it) => it.equals('foo')).existsOnce();
Implementation
@useResult
WidgetSelector<Semantics> whereValue(MatchProp<String> match) {
return withDiagnosticProp<String>('value', match);
}