Add round-tripping Equality/IComparable contract generation

CodeGen/Generators/UnitsNetGen/QuantityGenerator.cs

@@ -668,25 +668,25 @@ private void GenerateEqualityAndComparison()
         /// <summary>Returns true if less or equal to.</summary>
         public static bool operator <=({_quantity.Name} left, {_quantity.Name} right)
         {{
-            return left.Value <= right.GetValueAs(left.Unit);
+            return left.CompareTo(right) <= 0;
         }}
 
         /// <summary>Returns true if greater than or equal to.</summary>
         public static bool operator >=({_quantity.Name} left, {_quantity.Name} right)
         {{
-            return left.Value >= right.GetValueAs(left.Unit);
+            return left.CompareTo(right) >= 0;
         }}
 
         /// <summary>Returns true if less than.</summary>
         public static bool operator <({_quantity.Name} left, {_quantity.Name} right)
         {{
-            return left.Value < right.GetValueAs(left.Unit);
+            return left.CompareTo(right) == -1;
         }}
 
         /// <summary>Returns true if greater than.</summary>
         public static bool operator >({_quantity.Name} left, {_quantity.Name} right)
         {{
-            return left.Value > right.GetValueAs(left.Unit);
+            return left.CompareTo(right) == 1;
         }}
 
         /// <summary>Returns true if exactly equal.</summary>
@@ -715,7 +715,9 @@ public int CompareTo(object obj)
         /// <inheritdoc />
         public int CompareTo({_quantity.Name} other)
         {{
-            return _value.CompareTo(other.GetValueAs(this.Unit));
+            var asFirstUnit = other.GetValueAs(this.Unit);
+            var asSecondUnit = GetValueAs(other.Unit);
+            return (_value.CompareTo(asFirstUnit) - other.Value.CompareTo(asSecondUnit)) / 2;
         }}
 
         /// <inheritdoc />
@@ -792,7 +794,7 @@ public bool Equals({_quantity.Name} other, double tolerance, ComparisonType comp
         /// <returns>A hash code for the current {_quantity.Name}.</returns>
         public override int GetHashCode()
         {{
-            return new {{ QuantityType, Value, Unit }}.GetHashCode();
+            return QuantityType.GetHashCode();
         }}
 
         #endregion

CodeGen/Generators/UnitsNetGen/UnitTestBaseClassGenerator.cs

@@ -643,7 +643,7 @@ public void Convert_ChangeType_InvalidType_ThrowsInvalidCastException()
         public void GetHashCode_Equals()
         {{
             var quantity = {_quantity.Name}.From{_baseUnit.PluralName}(1.0);
-            Assert.Equal(new {{{_quantity.Name}.QuantityType, quantity.Value, quantity.Unit}}.GetHashCode(), quantity.GetHashCode());
+            Assert.Equal({_quantity.Name}.QuantityType.GetHashCode(), quantity.GetHashCode());
         }}
 ");