Feat: owner (alternative)

src/Blue.sol

@@ -39,6 +39,8 @@ contract Blue {
 
     // Storage.
 
+    // Owner.
+    address public owner;
     // User' supply balances.
     mapping(Id => mapping(address => uint)) public supplyShare;
     // User' borrow balances.
@@ -56,6 +58,19 @@ contract Blue {
     // Interests last update (used to check if a market has been created).
     mapping(Id => uint) public lastUpdate;
 
+    // Constructor.
+
+    constructor(address newOwner) {
+        owner = newOwner;
+    }
+
+    // Only owner functions.
+
+    function transferOwnership(address newOwner) external {
+        require(msg.sender == owner, "not owner");
+        owner = newOwner;
+    }
+
     // Markets management.
 
     function createMarket(Market calldata market) external {

test/forge/Blue.t.sol

@@ -14,6 +14,7 @@ import {OracleMock as Oracle} from "src/mocks/OracleMock.sol";
 contract BlueTest is Test {
     using MathLib for uint;
 
+    address private constant owner = address(0xdeed);
     address private constant borrower = address(1234);
     address private constant liquidator = address(5678);
     uint private constant lLTV = 0.8 ether;
@@ -28,7 +29,7 @@ contract BlueTest is Test {
 
     function setUp() public {
         // Create Blue.
-        blue = new Blue();
+        blue = new Blue(owner);
 
         // List a market.
         borrowableAsset = new ERC20("borrowable", "B", 18);
@@ -91,6 +92,30 @@ contract BlueTest is Test {
 
     // Tests
 
+    function testOwner(address newOwner) public {
+        Blue blue2 = new Blue(newOwner);
+
+        assertEq(blue2.owner(), newOwner, "owner");
+    }
+
+    function testTransferOwnership(address oldOwner, address newOwner) public {
+        Blue blue2 = new Blue(oldOwner);
+
+        vm.prank(oldOwner);
+        blue2.transferOwnership(newOwner);
+        assertEq(blue2.owner(), newOwner, "owner");
+    }
+
+    function testTransferOwnershipWhenNotOwner(address attacker, address newOwner) public {
+        vm.assume(attacker != address(0xdead));
+
+        Blue blue2 = new Blue(address(0xdead));
+
+        vm.prank(attacker);
+        vm.expectRevert("not owner");
+        blue2.transferOwnership(newOwner);
+    }
+
     function testSupply(uint amount) public {
         amount = bound(amount, 1, 2 ** 64);