Fee correctly used

Author: darunrs

lazer/evm/src/ExampleReceiver.sol

@@ -7,17 +7,20 @@ import {PythLazerLib} from "pyth-lazer/PythLazerLib.sol";
 
 contract ExampleReceiver {
     PythLazer pythLazer;
+    uint256 verification_fee;
     uint64 public price;
     uint64 public timestamp;
 
     constructor(address pythLazerAddress) {
         pythLazer = PythLazer(pythLazerAddress);
+        verification_fee = pythLazer.verification_fee();
     }
 
     function updatePrice(bytes calldata update) payable public {
-        (bytes memory payload,) = pythLazer.verifyUpdate{value: pythLazer.verification_fee()}(update);
-        if (msg.value > pythLazer.verification_fee()) {
-            payable(msg.sender).transfer(msg.value - pythLazer.verification_fee());
+        require(msg.value >= verification_fee, "Insufficient fee provided");
+        (bytes memory payload,) = pythLazer.verifyUpdate{value: verification_fee}(update);
+        if (msg.value > verification_fee) {
+            payable(msg.sender).transfer(msg.value - verification_fee);
         }
 
         (uint64 _timestamp, PythLazerLib.Channel channel, uint8 feedsLen, uint16 pos) =

lazer/evm/test/ExampleReceiver.t.sol

@@ -15,21 +15,27 @@ contract ExampleReceiverTest is Test {
         address lazer = makeAddr("lazer");
         PythLazer pythLazer = new PythLazer();
         pythLazer.initialize(lazer);
+
         vm.prank(lazer);
         pythLazer.updateTrustedSigner(trustedSigner, 3000000000000000);
+        uint256 fee = pythLazer.verification_fee();
 
         address consumer = makeAddr("consumer");
+        vm.deal(consumer, 10 wei);
+
         ExampleReceiver receiver = new ExampleReceiver(address(pythLazer));
         bytes memory update =
             hex"2a22999a577d3cc0202197939d736bc0dcf71b9dde7b9470e4d16fa8e2120c0787a1c0d744d0c39cc372af4d1ecf2d09e84160ca905f3f597d20e2eec144a446a0459ad600001c93c7d3750006240af373971c01010000000201000000000005f5e100";
         console.logBytes(update);
 
-        vm.deal(consumer, 1 ether);
         vm.prank(consumer);
-        receiver.updatePrice{value: pythLazer.verification_fee()}(update);
+        receiver.updatePrice{value: 5 * fee}(update);
+
         assertEq(receiver.price(), 100000000);
         assertEq(receiver.timestamp(), 1728479312975644);
-        assertEq(address(pythLazer).balance, pythLazer.verification_fee());
-        assertEq(consumer.balance, 1 ether - pythLazer.verification_fee());
+
+        assertEq(address(pythLazer).balance, fee);
+        assertEq(address(receiver).balance, 0);
+        assertEq(consumer.balance, 10 wei - fee);
     }
 }