feat: default & neg traits (#39)

* feat: Default

* feat: Neg for signed

* chore: cleanup

* chore: fmt

src/tests/test_wadray.cairo

@@ -401,3 +401,12 @@ fn test_display_and_debug() {
     assert_eq!(format!("{}", r), "456", "Ray display");
     assert_eq!(format!("{:?}", r), "456", "Ray debug");
 }
+
+#[test]
+fn test_default() {
+    let w: Wad = Default::default();
+    assert_eq!(w.val, 0, "Wad default");
+
+    let r: Ray = Default::default();
+    assert_eq!(r.val, 0, "Ray default");
+}

src/tests/test_wadray_signed.cairo

@@ -501,4 +501,42 @@ mod test_wadray_signed {
         let rr: SignedRay = StorePacking::unpack(StorePacking::pack(r));
         assert_eq!(r, rr, "SignedRay packing 4");
     }
+
+    #[test]
+    fn test_default() {
+        let w: SignedWad = Default::default();
+        assert_eq!(w.val, 0, "SignedWad default val");
+        assert!(w.sign == false, "SignedWad default sign");
+
+        let r: SignedRay = Default::default();
+        assert_eq!(r.val, 0, "SignedRay default val");
+        assert!(r.sign == false, "SignedRay default sign");
+    }
+
+    #[test]
+    fn test_neg() {
+        let wp = SignedWad { val: 123, sign: false };
+        let wpn = -wp;
+        assert_eq!(wpn.val, 123, "SignedWad neg val");
+        assert!(wpn.sign, "SignedWad neg sign");
+        assert_eq!(-wpn, wp, "SignedWad double neg");
+
+        let wp0 = SignedWad { val: 0, sign: false };
+        let wpn0 = -wp0;
+        assert_eq!(wpn0.val, 0, "SignedWad zero neg val");
+        assert!(wpn0.sign, "SignedWad zero neg sign");
+        assert_eq!(-wpn0, wp0, "SignedWad zero double neg");
+
+        let rp = SignedRay { val: 123, sign: false };
+        let rpn = -rp;
+        assert_eq!(rpn.val, 123, "SignedRay neg val");
+        assert!(rpn.sign, "SignedRay neg sign");
+        assert_eq!(-rpn, rp, "SignedRay double neg");
+
+        let rp0 = SignedRay { val: 0, sign: false };
+        let rpn0 = -rp0;
+        assert_eq!(rpn0.val, 0, "SignedRay zero neg val");
+        assert!(rpn0.sign, "SignedRay zero neg sign");
+        assert_eq!(-rpn0, rp0, "SignedRay zero double neg");
+    }
 }

src/wadray.cairo

@@ -1,6 +1,7 @@
 use core::fmt::{Debug, Display, Error, Formatter};
 use core::num::traits::{One, Zero, Bounded};
 use core::ops::{AddAssign, SubAssign, MulAssign, DivAssign};
+use core::traits::Default;
 
 
 pub const WAD_DECIMALS: u8 = 18;
@@ -482,3 +483,16 @@ pub impl DebugRay of Debug<Ray> {
         Display::fmt(self, ref f)
     }
 }
+
+// Default
+pub impl DefaultWad of Default<Wad> {
+    fn default() -> Wad {
+        Wad { val: 0 }
+    }
+}
+
+pub impl DefaultRay of Default<Ray> {
+    fn default() -> Ray {
+        Ray { val: 0 }
+    }
+}

src/wadray_signed.cairo

@@ -1,6 +1,7 @@
 use core::fmt::{Debug, Display, Error, Formatter};
 use core::num::traits::{One, Zero, Bounded};
 use core::ops::{AddAssign, SubAssign, MulAssign, DivAssign};
+use core::traits::{Default, Neg};
 use starknet::storage_access::StorePacking;
 use wadray::wadray::{DIFF, Ray, RAY_ONE, u128_rdiv, u128_rmul, u128_wdiv, u128_wmul, Wad, WAD_ONE};
 
@@ -545,3 +546,30 @@ pub impl DebugSignedRay of Debug<SignedRay> {
         Display::fmt(self, ref f)
     }
 }
+
+// Default
+pub impl DefaultSignedWad of Default<SignedWad> {
+    fn default() -> SignedWad {
+        SignedWad { val: 0, sign: false }
+    }
+}
+
+pub impl DefaultSignedRay of Default<SignedRay> {
+    fn default() -> SignedRay {
+        SignedRay { val: 0, sign: false }
+    }
+}
+
+// Neg
+pub impl SignedWadNeg of Neg<SignedWad> {
+    fn neg(a: SignedWad) -> SignedWad {
+        SignedWad { val: a.val, sign: !a.sign }
+    }
+}
+
+
+pub impl SignedRayNeg of Neg<SignedRay> {
+    fn neg(a: SignedRay) -> SignedRay {
+        SignedRay { val: a.val, sign: !a.sign }
+    }
+}