Merge with dev

.solcover.js

@@ -12,12 +12,16 @@ module.exports = {
     copyPackages: ['openzeppelin'],
     skipFiles: [
       'Migrations.sol',
+
       'mocks/MockOracle.sol',
       'mocks/MockERC20.sol',
       'mocks/MockCtoken.sol',
       'mocks/MockCompoundOracle.sol',
       'mocks/MockUniswapFactory.sol',
-      'mocks/MockOtokensExchange.sol'
+      'mocks/MockOtokensExchange.sol',
+      'echidna/contracts/TestOptionsContract.sol',
+      'echidna/contracts/TestOptionsExchange.sol',
+      'echidna/EchidnaOptionsContract.sol'
     ]
   };
 

.solhintignore

@@ -1,2 +1,4 @@
 contracts/lib/
 contracts/Migrations.sol
+contracts/packages/
+contracts/echidna/

contracts/OptionsContract.sol

@@ -3,12 +3,11 @@ pragma solidity ^0.5.10;
 import "./interfaces/OracleInterface.sol";
 import "./interfaces/UniswapFactoryInterface.sol";
 import "./interfaces/UniswapExchangeInterface.sol";
-
-import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
-import "@openzeppelin/contracts/token/ERC20/ERC20Detailed.sol";
-import "@openzeppelin/contracts/ownership/Ownable.sol";
-import "@openzeppelin/contracts/math/SafeMath.sol";
+import "./packages/ERC20.sol";
+import "./packages/IERC20.sol";
+import "./packages/ERC20Detailed.sol";
+import "./packages/Ownable.sol";
+import "./packages/SafeMath.sol";
 
 
 /**
@@ -391,7 +390,7 @@ contract OptionsContract is Ownable, ERC20 {
         uint64 underlyingPerOTokenExp = uint64(
             oTokenExchangeRate.exponent - underlyingExp
         );
-        return oTokensToExercise.mul(10**underlyingPerOTokenExp);
+        return uint256(oTokensToExercise.mul(10**underlyingPerOTokenExp));
     }
 
     /**
@@ -971,13 +970,17 @@ contract OptionsContract is Ownable, ERC20 {
         uint256 amtCollateralToPay = 0;
         if (amtCollateralToPayExp > 0) {
             uint32 exp = uint32(amtCollateralToPayExp);
-            amtCollateralToPay = amtCollateralToPayInEthNum.mul(10**exp).div(
-                collateralToEthPrice
+            amtCollateralToPay = uint256(
+                amtCollateralToPayInEthNum.mul(10**exp).div(
+                    collateralToEthPrice
+                )
             );
         } else {
             uint32 exp = uint32(-1 * amtCollateralToPayExp);
-            amtCollateralToPay = (amtCollateralToPayInEthNum.div(10**exp)).div(
-                collateralToEthPrice
+            amtCollateralToPay = uint256(
+                (amtCollateralToPayInEthNum.div(10**exp)).div(
+                    collateralToEthPrice
+                )
             );
         }
 

contracts/OptionsExchange.sol

@@ -3,7 +3,7 @@ pragma solidity 0.5.10;
 import "./interfaces/CompoundOracleInterface.sol";
 import "./interfaces/UniswapFactoryInterface.sol";
 import "./interfaces/UniswapExchangeInterface.sol";
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import "./packages/IERC20.sol";
 
 
 contract OptionsExchange {

contracts/OptionsFactory.sol

@@ -2,8 +2,8 @@ pragma solidity 0.5.10;
 
 import "./oToken.sol";
 import "./lib/StringComparator.sol";
-import "@openzeppelin/contracts/ownership/Ownable.sol";
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import "./packages/Ownable.sol";
+import "./packages/IERC20.sol";
 
 
 contract OptionsFactory is Ownable {

contracts/Oracle.sol

@@ -2,10 +2,10 @@ pragma solidity 0.5.10;
 
 import "./interfaces/CompoundOracleInterface.sol";
 import "./interfaces/CTokenInterface.sol";
-import "@openzeppelin/contracts/token/ERC20/ERC20Detailed.sol";
-import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-import "@openzeppelin/contracts/ownership/Ownable.sol";
-import "@openzeppelin/contracts/math/SafeMath.sol";
+import "./packages/ERC20Detailed.sol";
+import "./packages/ERC20.sol";
+import "./packages/Ownable.sol";
+import "./packages/SafeMath.sol";
 
 
 contract Oracle is Ownable {

contracts/echidna/EchidnaOptionsContract.sol

@@ -0,0 +1,79 @@
+pragma solidity ^0.5.10;
+
+import "./contracts/TestOptionsContract.sol";
+
+
+contract EchidnaOptionsContract is TestOptionsContract {
+    function echidna_windowsize_lessthan_equal_expiry()
+        public
+        view
+        returns (bool)
+    {
+        return windowSize <= expiry;
+    }
+
+    function echidna_collateral_exponent_withen_exponent_range()
+        public
+        view
+        returns (bool)
+    {
+        return ((collateralExp <= 30) && (collateralExp >= -30));
+    }
+
+    function echidna_underlying_exponent_withen_exponent_range()
+        public
+        view
+        returns (bool)
+    {
+        return ((underlyingExp <= 30) && (underlyingExp >= -30));
+    }
+
+    function echidna_strike_exponent_withen_exponent_range()
+        public
+        view
+        returns (bool)
+    {
+        return ((strikePrice.exponent <= 30) && (strikePrice.exponent >= -30));
+    }
+
+    function echidna_exchange_rate_exponent_withen_exponent_range()
+        public
+        view
+        returns (bool)
+    {
+        return ((oTokenExchangeRate.exponent <= 30) &&
+            (oTokenExchangeRate.exponent >= -30));
+    }
+
+    function echidna_liquiadtion_incentive_lessthan_equal_20percent()
+        public
+        view
+        returns (bool)
+    {
+        return liquidationIncentive.value <= 200;
+    }
+
+    function echidna_liquiadtion_factor_lessthan_equal_100percent()
+        public
+        view
+        returns (bool)
+    {
+        return liquidationFactor.value <= 1000;
+    }
+
+    function echidna_transaction_fee_lessthan_equal_10percent()
+        public
+        view
+        returns (bool)
+    {
+        return transactionFee.value <= 100;
+    }
+
+    function echidna_min_collateralization_ration_greaterthan_equal_1()
+        public
+        view
+        returns (bool)
+    {
+        return minCollateralizationRatio.value >= 10;
+    }
+}

contracts/echidna/EchidnaOptionsContract.yaml

@@ -0,0 +1 @@
+prefix: "echidna_"