test: add complete tests

script/1.0.0/input.json

@@ -8,7 +8,7 @@
             "initialOwner": "0x48789ECd4317eCc8dBdB1d06EF39F01c5862a941"
         },
         "Counter": {
-            "number": 3
+            "number": 10
         }
     }
 }

test/1.0.0/Counter.t.sol

@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.22;
+
+import "forge-std/Test.sol";
+import "test/util/TestHelpers.sol";
+
+import "script/1.0.0/Deploy.s.sol";
+
+abstract contract BeforeScript is Test, TestHelpers, CounterDeployer {
+    Counter internal counter;
+
+    function setUp() public {
+        (counter, , ) = deployCounter_NoInit(makeAddr(""));
+    }
+}
+
+contract CounterTest_Zero is BeforeScript {
+    function test_Initializes(uint256 number) public {
+        counter.initialize(number);
+        assertEq(counter.number(), number);
+    }
+}
+
+abstract contract AfterScript is Test, TestHelpers, Deploy {
+    function setUp() public virtual {
+        run();
+    }
+}
+
+contract CounterTest_Initialized is AfterScript {
+    function test_IsInitialized() public {
+        assertEq(counter.number(), 10);
+    }
+
+    function test_RevertsIf_InitializedAgain() public {
+        vm.expectRevert(Initializable.InvalidInitialization.selector);
+        counter.initialize(1);
+    }
+
+    function test_IncrementsNumber() public {
+        counter.increment();
+        assertEq(counter.number(), 11);
+    }
+
+    function testFuzz_SetsNumber(uint256 x) public {
+        counter.setNumber(x);
+        assertEq(counter.number(), x);
+    }
+
+    function test_ReturnsVersion() public {
+        assertEq(counter.version(), "1.0.0");
+    }
+}

test/util/TestHelpers.sol

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.22;
+
+import "forge-std/Test.sol";
+
+abstract contract TestHelpers is Test {
+    Account internal DEPLOYER;
+
+    constructor() {
+        DEPLOYER = makeAccount("DEPLOYER");
+        vm.setEnv("PRIVATE_KEY", vm.toString(DEPLOYER.key));
+    }
+}