This is an add-in for Fody 
Generate the Equals, GetHashCode and operators methods from properties or fields explicitly decorated with the [Equals] Attribute.
This add in is inspired by Equals.Fody, but uses only explicit annotated members to generate the code.
Install the Equatable.Fody NuGet package and update the Fody NuGet package:
PM> Install-Package Equatable.Fody
PM> Update-Package Fody
The Update-Package Fody is required since NuGet always defaults to the oldest, and most buggy, version of any dependency.
[ImplementsEquatable]
public class Point
{
[Equals]
private int _x;
[Equals(StringComparison.OrdinalIgnoreCase)]
public string Y { get; set; }
public int Z { get; set; }
[CustomEquals]
bool CustomLogic(Point other)
{
return Z == other.Z || Z == 0 || other.Z == 0;
}
}
[ImplementsEquatable]
public class CustomGetHashCode
{
[Equals]
private int _x;
[Equals]
public int Y { get; set; }
public int Z { get; set; }
[CustomGetHashCode]
int CustomGetHashCodeMethod()
{
return 42;
}
}public class Point : IEquatable<Point>
{
private int _x;
public string Y { get; set; }
public int Z { get; set; }
private bool CustomLogic(Point other)
{
if (this.Z != other.Z && this.Z != 0)
return other.Z == 0;
return true;
}
private static bool <InternalEquals>(Point left, Point right)
{
if (left.CustomLogic(right) && left._x == right._x)
return StringComparer.OrdinalIgnoreCase.Equals(left.Y, right.Y);
return false;
}
public virtual bool Equals(Point other)
{
if ((object) other == null)
return false;
if ((object) this == (object) other)
return true;
return Point.<InternalEquals>(this, other);
}
public override int GetHashCode()
{
return <HashCode>.Aggregate(<HashCode>.Aggregate(0, this._x), <HashCode>.GetStringHashCode(this.Y, StringComparer.OrdinalIgnoreCase));
}
public override bool Equals(object obj)
{
return this.Equals(obj as Point);
}
public static bool operator ==(Point left, Point right)
{
return Point.<InternalEquals>(left, right);
}
public static bool operator !=(Point left, Point right)
{
return !Point.<InternalEquals>(left, right);
}
}
public class CustomGetHashCode : IEquatable<CustomGetHashCode>
{
private int _x;
public int Y { get; set; }
public int Z { get; set; }
private int CustomGetHashCodeMethod()
{
return 42;
}
private static bool <InternalEquals>(CustomGetHashCode left, CustomGetHashCode right)
{
if (left._x == right._x)
return left.Y == right.Y;
return false;
}
public virtual bool Equals(CustomGetHashCode other)
{
if ((object) other == null)
return false;
if ((object) this == (object) other)
return true;
return CustomGetHashCode.<InternalEquals>(this, other);
}
public override int GetHashCode()
{
return <HashCode>.Aggregate(<HashCode>.Aggregate(<HashCode>.Aggregate(0, this.CustomGetHashCodeMethod()), this._x), this.Y);
}
public override bool Equals(object obj)
{
return this.Equals(obj as CustomGetHashCode);
}
public static bool operator ==(CustomGetHashCode left, CustomGetHashCode right)
{
return CustomGetHashCode.<InternalEquals>(left, right);
}
public static bool operator !=(CustomGetHashCode left, CustomGetHashCode right)
{
return !CustomGetHashCode.<InternalEquals>(left, right);
}
}
internal static class <HashCode>
{
static int Aggregate(int hash1, int hash2)
{
return (hash1 << 5) + hash1 ^ hash2;
}
static int GetHashCode(object value)
{
if (value == null)
return 0;
return value.GetHashCode();
}
static int GetStringHashCode(string value, StringComparer comparer)
{
if (value == null)
return 0;
return comparer.GetHashCode(value);
}
}