add encodeFunctionCall to upgrade example

examples/upgradeable/contracts/DemoV2.sol

@@ -3,7 +3,13 @@ pragma solidity ^0.8.9;
 
 // A contrived example of a contract that can be upgraded
 contract DemoV2 {
+  string public name;
+
   function version() public pure returns (string memory) {
     return "2.0.0";
   }
+
+  function setName(string memory _name) public {
+    name = _name;
+  }
 }

examples/upgradeable/ignition/modules/UpgradeModule.js

@@ -15,10 +15,19 @@ const upgradeModule = buildModule("UpgradeModule", (m) => {
   // This is the new version of the Demo contract that we want to upgrade to.
   const demoV2 = m.contract("DemoV2");
 
+  // The `upgradeAndCall` function on the ProxyAdmin contract allows us to upgrade the proxy
+  // and call a function on the new implementation contract in a single transaction.
+  // To do this, we need to encode the function call data for the function we want to call.
+  // We'll then pass this encoded data to the `upgradeAndCall` function.
+  const encodedFunctionCall = m.encodeFunctionCall(demoV2, "setName", [
+    "Example Name",
+  ]);
+
   // Upgrade the proxy to the new version of the Demo contract.
-  // This function also accepts a data parameter, which can be used to call a function,
-  // but we don't need it here so we pass an empty hex string ("0x").
-  m.call(proxyAdmin, "upgradeAndCall", [proxy, demoV2, "0x"], {
+  // This function also accepts a data parameter, which accepts encoded function call data.
+  // We pass the encoded function call data we created above to the `upgradeAndCall` function
+  // so that the `setName` function is called on the new implementation contract after the upgrade.
+  m.call(proxyAdmin, "upgradeAndCall", [proxy, demoV2, encodedFunctionCall], {
     from: proxyAdminOwner,
   });
 

examples/upgradeable/test/ProxyDemo.js

@@ -22,5 +22,13 @@ describe("Demo Proxy", function () {
 
       expect(await demo.connect(otherAccount).version()).to.equal("2.0.0");
     });
+
+    it("Should have set the name during upgrade", async function () {
+      const [owner, otherAccount] = await ethers.getSigners();
+
+      const { demo } = await ignition.deploy(UpgradeModule);
+
+      expect(await demo.connect(otherAccount).name()).to.equal("Example Name");
+    });
   });
 });