wad representation (#498)

* wad representation

* move errors to mod.rs

Author: ozgunozerk

packages/contract-utils/src/math/i128_fixed_point.rs

@@ -26,7 +26,7 @@ SOFTWARE.
 
 use soroban_sdk::{panic_with_error, Env, I256};
 
-use crate::math::soroban_fixed_point::{SorobanFixedPoint, SorobanFixedPointError};
+use crate::math::{soroban_fixed_point::SorobanFixedPoint, SorobanFixedPointError};
 
 /// Performs floor(r / z)
 fn div_floor(r: i128, z: i128) -> Option<i128> {
@@ -66,7 +66,7 @@ impl SorobanFixedPoint for i128 {
 fn scaled_mul_div_floor(x: &i128, env: &Env, y: &i128, z: &i128) -> i128 {
     match x.checked_mul(*y) {
         Some(r) => div_floor(r, *z)
-            .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::ZeroDenominator)),
+            .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::DivisionByZero)),
         None => {
             // scale to i256 and retry
             let res = crate::math::i256_fixed_point::mul_div_floor(
@@ -76,7 +76,7 @@ fn scaled_mul_div_floor(x: &i128, env: &Env, y: &i128, z: &i128) -> i128 {
                 &I256::from_i128(env, *z),
             );
             res.to_i128()
-                .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::ResultOverflow))
+                .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::Overflow))
         }
     }
 }
@@ -85,7 +85,7 @@ fn scaled_mul_div_floor(x: &i128, env: &Env, y: &i128, z: &i128) -> i128 {
 fn scaled_mul_div_ceil(x: &i128, env: &Env, y: &i128, z: &i128) -> i128 {
     match x.checked_mul(*y) {
         Some(r) => div_ceil(r, *z)
-            .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::ZeroDenominator)),
+            .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::DivisionByZero)),
         None => {
             // scale to i256 and retry
             let res = crate::math::i256_fixed_point::mul_div_ceil(
@@ -95,7 +95,7 @@ fn scaled_mul_div_ceil(x: &i128, env: &Env, y: &i128, z: &i128) -> i128 {
                 &I256::from_i128(env, *z),
             );
             res.to_i128()
-                .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::ResultOverflow))
+                .unwrap_or_else(|| panic_with_error!(env, SorobanFixedPointError::Overflow))
         }
     }
 }

packages/contract-utils/src/math/i256_fixed_point.rs

@@ -26,7 +26,7 @@ SOFTWARE.
 
 use soroban_sdk::{panic_with_error, Env, I256};
 
-use crate::math::soroban_fixed_point::{SorobanFixedPoint, SorobanFixedPointError};
+use crate::math::{soroban_fixed_point::SorobanFixedPoint, SorobanFixedPointError};
 
 impl SorobanFixedPoint for I256 {
     fn fixed_mul_floor(&self, env: &Env, y: &I256, denominator: &I256) -> I256 {
@@ -44,7 +44,7 @@ pub(crate) fn mul_div_floor(env: &Env, x: &I256, y: &I256, z: &I256) -> I256 {
     let r = x.mul(y);
 
     if z.clone() == zero {
-        panic_with_error!(env, SorobanFixedPointError::ZeroDenominator);
+        panic_with_error!(env, SorobanFixedPointError::DivisionByZero);
     }
 
     if r < zero || (r > zero && z.clone() < zero) {
@@ -64,7 +64,7 @@ pub(crate) fn mul_div_ceil(env: &Env, x: &I256, y: &I256, z: &I256) -> I256 {
     let r = x.mul(y);
 
     if z.clone() == zero {
-        panic_with_error!(env, SorobanFixedPointError::ZeroDenominator);
+        panic_with_error!(env, SorobanFixedPointError::DivisionByZero);
     }
 
     if z.clone() < zero || r <= zero {

packages/contract-utils/src/math/mod.rs

@@ -2,5 +2,20 @@ pub mod fixed_point;
 mod i128_fixed_point;
 mod i256_fixed_point;
 mod soroban_fixed_point;
+pub mod wad;
 
 mod test;
+
+use soroban_sdk::contracterror;
+
+// ################## ERRORS ##################
+
+#[contracterror]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+#[repr(u32)]
+pub enum SorobanFixedPointError {
+    /// Arithmetic overflow occurred
+    Overflow = 1500,
+    /// Division by zero
+    DivisionByZero = 1501,
+}

packages/contract-utils/src/math/soroban_fixed_point.rs

@@ -24,7 +24,7 @@ SOFTWARE.
 // Based on the Soroban fixed-point mathematics library
 // Original implementation: https://github.com/script3/soroban-fixed-point-math
 
-use soroban_sdk::{contracterror, Env};
+use soroban_sdk::Env;
 
 // @dev - more detail about the forced panic can be found here: https://github.com/stellar/rs-soroban-env/pull/1091
 //
@@ -50,17 +50,3 @@ pub trait SorobanFixedPoint: Sized {
     /// occurs, or the result does not fit in Self.
     fn fixed_mul_ceil(&self, env: &Env, y: &Self, denominator: &Self) -> Self;
 }
-
-// ################## ERRORS ##################
-
-#[contracterror]
-#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
-#[repr(u32)]
-pub enum SorobanFixedPointError {
-    /// The operation failed because the denominator is 0.
-    ZeroDenominator = 1500,
-    /// The operation failed because a phantom overflow occurred.
-    PhantomOverflow = 1501,
-    /// The operation failed because the result does not fit in Self.
-    ResultOverflow = 1502,
-}