public void Call_NullExpressionPassed_NullReferenceExceptionThrown()
{
// Arrange
CacheCaller cacheCallerUnderTest = new CacheCaller();
// Act and assert
Assert.Throws <NullReferenceException>(() => cacheCallerUnderTest.Call(null));
}
public void Call_ExpressionContainsVariable_ArgumentOutOfRangeThrown()
{
// Arrange
int a = 5;
Expression <Func <int> > expression = () => a;
CacheCaller cacheCallerUnderTest = new CacheCaller();
// Act and assert
Assert.Throws <ArgumentOutOfRangeException>(() => cacheCallerUnderTest.Call(expression));
}
public void Call_CalledWithoutMethods_NoMethodsCalledAndExpressionEvaluated()
{
// Arrange
Expression <Func <int> > expressionWithoutMethods = () => - 5 + 2 * 3 - 20 / 4;
int expectedResult = expressionWithoutMethods.Compile().Invoke();
CacheCaller callerUnderTest = new CacheCaller();
// Act
int actualResult = callerUnderTest.Call(expressionWithoutMethods);
// Assert
Assert.Equal(0, _aCalledTimes);
Assert.Equal(0, _bCalledTimes);
Assert.Equal(0, _cCalledTimes);
Assert.Equal(expectedResult, actualResult);
}
public void Call_MethodsCalledTwoTimesWithDifferenctArgs_EachMethodExceptACalledTwice()
{
// Arrange
Expression <Func <int> > expression = () => A() * A() + B(10) / B(5) - C(1, 5) + C(5, 1) + -10;
int expectedResult = expression.Compile().Invoke();
ResetCalledTimes();
CacheCaller caller = new CacheCaller();
// Act
int actualResult = caller.Call(expression);
// Assert
Assert.Equal(1, _aCalledTimes);
Assert.Equal(2, _bCalledTimes);
Assert.Equal(2, _cCalledTimes);
Assert.Equal(expectedResult, actualResult);
}
public void Call_OneCallForEachMethod_EachMethodCalledOnce()
{
// Arrange
Expression <Func <int> > expression = () => C(B(A()), 5) + 4;
int expectedResult = expression.Compile().Invoke();
ResetCalledTimes();
CacheCaller caller = new CacheCaller();
// Act
int actualResult = caller.Call(expression);
// Assert
Assert.Equal(1, _aCalledTimes);
Assert.Equal(1, _bCalledTimes);
Assert.Equal(1, _cCalledTimes);
Assert.Equal(expectedResult, actualResult);
}