public void UomFactorWorks()
{
ITermVisitor myTermVisitor = new MyTermVisitor(new UnitConverter(), new FxRateRepository(new TestFxPriceSourceStub()));
const string inputFunction = "2*UomConvert(MT,Kg)";
var(function, rawTerms) =
MyGrammarExpressionEvaluator.EvaluateExpression(inputFunction);
rawTerms.ToList().ForEach(t => t.Accept(myTermVisitor)); // hydrate
var hydratedTerms = new List <IGrammarTerm>();
var signal = new AutoResetEvent(false);
var disposable = myTermVisitor.GetAllTerms().Take(1).Subscribe(terms =>
{
hydratedTerms.AddRange(terms);
signal.Set();
});
signal.WaitOne();
disposable.Dispose();
var result = function.Invoke(hydratedTerms);
Assert.That(result, Is.EqualTo(2000m));
}
public void BasicMathsWork(string numberExpression, decimal expectedResult)
{
var(function, _) = MyGrammarExpressionEvaluator.EvaluateExpression(numberExpression);
var result = function.Invoke(new List <IGrammarTerm>());
Assert.That(result, Is.EqualTo(expectedResult));
}
public void VisitNumberExpressionWorks()
{
const string numberExpression = "2";
var evaluator = MyGrammarExpressionEvaluator.EvaluateExpression(numberExpression);
var result = evaluator.Invoke(new List <ExpressionTerm>());
Assert.That(result, Is.EqualTo(2m));
}
public void UomFactorWorks()
{
ITermVisitor myTermVisitor = new MyTermVisitor();
const string inputFunction = "2*UomConvert(MT,Kg)";
var(function, rawTerms) =
MyGrammarExpressionEvaluator.EvaluateExpression(inputFunction);
rawTerms.ToList().ForEach(t => t.Accept(myTermVisitor)); // hydrate
var hydratedTerms = myTermVisitor.GetAllTerms();
var result = function.Invoke(hydratedTerms);
Assert.That(result, Is.EqualTo(2000m));
}
public async Task FxRateTicksWork()
{
// Add test price source.
ITermVisitor myTermVisitor = new MyTermVisitor(new UnitConverter(), new FxRateRepository(new TestFxPriceSourceStub()));
const string inputFunction = "FXRate(EURUSD)";
var(function, rawTerms) =
MyGrammarExpressionEvaluator.EvaluateExpression(inputFunction);
rawTerms.ToList().ForEach(t => t.Accept(myTermVisitor)); // hydrate
var hydratedTerms = await myTermVisitor.GetAllTerms().Take(1);
var result = function.Invoke(hydratedTerms as IReadOnlyList <IGrammarTerm>);
// the actual rate is not testable as is.
// we'll come back to this hence the (within)
Assert.That(result, Is.EqualTo(1m));
}
public IObservable <decimal> Price(string product)
{
return(Observable.Create <decimal>(obs =>
{
try
{
// todo no need to have nested subscriptions here.
var disposable = new CompositeDisposable();
var productStream =
_productRepository.GetProduct(product)
.Subscribe(p =>
{
var(priceExpression, rawTerms) =
MyGrammarExpressionEvaluator.EvaluateExpression(p.PriceExpression);
var termVisitor = new MyTermVisitor(_unitConverter, _fxRateRepository);
rawTerms.ForEach(t => t.Accept(termVisitor));
var subscription = termVisitor.GetAllTerms().Subscribe(terms =>
{
var price = priceExpression.Invoke(terms as IReadOnlyList <IGrammarTerm>);
obs.OnNext(price);
});
disposable.Add(subscription);
});
disposable.Add(productStream);
return disposable;
}
catch (Exception e)
{
obs.OnError(e);
throw;
}
}));
}