/// <summary>
/// Test if two float are equal by testing that the
/// pattern of bits returned by
/// BitConverter.ToInt32(BitConverter.GetBytes(float), 0) are equal
/// (BitConverter does not have SingleToInt32Bits() so we use this
/// 2-call workaround <see href="http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=426391"/>
/// to roll our own implementation).
/// This handles NaNs, Infinties, and <code>-0.0.
/// It is compatible with the hash code generated by
/// HashCodeBuilder.
/// </summary>
/// <param name="lhs">the left hand float</param>
/// <param name="rhs">the right hand float</param>
/// <returns>EqualsBuilder - used to chain calls.</returns>
public EqualsBuilder Append(float lhs, float rhs)
{
if (isEqual == false)
{
return(this);
}
// java: return append(Float.floatToIntBits(lhs), Float.floatToIntBits(rhs));
return(Append(
BitConverterUtil.SingleToInt32Bits(lhs),
BitConverterUtil.SingleToInt32Bits(rhs)));
}
public void TestSingleToInt32Bits()
{
Assert.IsTrue(BitConverterUtil.SingleToInt32Bits(24.154f) == 1103182692);
Assert.IsTrue(BitConverterUtil.SingleToInt32Bits(1.0f) == 1065353216);
Assert.IsTrue(BitConverterUtil.SingleToInt32Bits(float.PositiveInfinity) == (int)0x7f800000U);
// Use "unchecked" syntax to avoid compiler error: "Constant value '4286578688' cannot be
// converted to a 'int' (use 'unchecked' syntax to override). The literal 0xff800000
// (4286578688)won't fit in a signed int without overflow.
// C# statements can execute in either checked or unchecked context. In a checked context,
// arithmetic overflow raises an exception. In an unchecked context, arithmetic overflow
// is ignored and the result is truncated.
unchecked
{
Assert.IsTrue(BitConverterUtil.SingleToInt32Bits(float.NegativeInfinity) == (int)0xff800000U);
}
}
