public void TryInvert_Should_ReturnTrue_When_TimeSpan()
{
var value = TimeSpan.FromHours(3);
Assert.True(CalculateUtilities.TryInvert(value, out var _result));
Assert.Equal(value * -1, _result);
}
public void TryInvert_Should_ReturnTrue_When_Int()
{
const int value = 3;
Assert.True(CalculateUtilities.TryInvert(value, out var _result));
Assert.Equal(value * -1, _result);
}
public void TryInvert_Should_ReturnTrue_When_Double()
{
const double value = 3.2;
Assert.True(CalculateUtilities.TryInvert(value, out var _result));
Assert.True(CompareUtilities.EqualsWithinTolerance(value * -1, _result, 6));
}
/// <summary>
/// Initializes an instance of <see cref="PropertyMutation"/>
/// </summary>
/// <param name="value"></param>
/// <param name="propertySelector"></param>
/// <exception cref="ArgumentException">Throws when <see cref="TValue"/> not invertable.</exception>
public PropertyMutation(
TValue value,
Expression <Func <T, TValue> > propertySelector)
{
PropertySelector = propertySelector;
Value = value;
if (!CalculateUtilities.TryInvert(value, out var _invertValue))
{
throw new ArgumentException($"{nameof(value)} is not invertable.", nameof(value));
}
_valueAction = propertySelector.ToAddAction(value);
_revertValueAction = propertySelector.ToAddAction(_invertValue);
}
public void TryInvert_Should_ReturnFalse_When_String()
{
const string value = "String";
Assert.False(CalculateUtilities.TryInvert(value, out _));
}