add tests

src/Faucet.sol

@@ -25,5 +25,8 @@ contract Faucet {
         emit Withdrawal(msg.sender, withdraw_amount);
     }
 
+    /**
+     * @notice Receive ether， people can send ether that they are not gonna use to this contract
+     */
     receive() external payable {}
 }

test/Faucet.t.sol

@@ -3,12 +3,43 @@ pragma solidity ^0.8.24;
 
 import {Test} from "forge-std/Test.sol";
 import {Faucet} from "src/Faucet.sol";
+import {Deploy} from "script/Deploy.s.sol";
 
 contract FaucetTest is Test {
+    Faucet faucet;
 
-    function test_withdraw() public {
-        Faucet faucet = new Faucet();
-        faucet.deposit{value: 1 ether}();
+    address testUser = makeAddr("testUser");
+
+    function setup() public {
+        Deploy deploy = new Deploy();
+        faucet = deploy.run();
+
+        //transfer some funds to the faucet
+        //put it here, so for the production, we can fund the faucet manually, for security reasons.
+        vm.startBroadcast();
+        vm.deal(address(faucet), 100 ether);
+        vm.stopBroadcast();
+    }
+
+
+    function test_withdrawTooLarge() public {
+        vm.prank(testUser);
+        vm.expectRevert(Faucet.Faucet__amountTooLarge);
+        faucet.withdraw(10 ether);
+    }
+
+    function test_withdraw(uint amount) public {
+        vm.prank(testUser);
+        uint _amount = amount % 0.1 ether;
+        faucet.withdraw(_amount);
+        assertEq(address(testUser).balance, _amount);
+    }
+
+    function test_rateLimit() public {
+        vm.prank(testUser);
+        faucet.withdraw(0.01 ether);
+        vm.expectRevert(Faucet.Faucet__rateLimt);
+        faucet.withdraw(0.01 ether);
     }
 
 }