vm.expectCall unexpected behavior

[garyghayrat]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.2.0 (e807429 2023-05-04T00:03:45.171389475Z)

What command(s) is the bug in?

forge test

Operating System

Linux

Describe the bug

vm.expectCall is giving contradictory errors when used within a helper function and a loop.

To reproduce:

1. git clone git@github.com:ScopeLift/umbra-protocol.git
2. git checkout expect-call-issue
3. cd contracts-periphery/ && cp .env.example .env and fill in ETH_RPC_URL in .env
4. forge test --mc UniswapWithdrawHookTest

Relevant lines of codes are at 71-83 and 151-153.

In this case:
vm.expectCall( address(withdrawHook), abi.encodeWithSelector(withdrawHook.tokensWithdrawn.selector) );

When you run the test command at step 4. You'll see this error:

Failing tests:
Encountered 2 failing tests in test/UniswapWithdrawHook.fork.1.t.sol:UniswapWithdrawHookTest
[FAIL. Reason: Expected at least one call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de, but got **none** Counterexample: calldata=0x3d93c91a0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCall(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)
[FAIL. Reason: Expected at least one call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de, but got **none** Counterexample: calldata=0xc410223f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCallOnBehalf(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)

If you change the code to:
vm.expectCall( address(withdrawHook), abi.encodeWithSelector(withdrawHook.tokensWithdrawn.selector), **0** );
and then run the test, you'll see:

Failing tests:
Encountered 2 failing tests in test/UniswapWithdrawHook.fork.1.t.sol:UniswapWithdrawHookTest
[FAIL. Reason: Expected call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de to be made 0 time(s), but was called 10 time(s) Counterexample: calldata=0x3d93c91a0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCall(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)
[FAIL. Reason: Expected call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de to be made 0 time(s), but was called 10 time(s) Counterexample: calldata=0xc410223f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCallOnBehalf(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)

If you change the code to:
vm.expectCall( address(withdrawHook), abi.encodeWithSelector(withdrawHook.tokensWithdrawn.selector), **10** );
and then run the test, you'll see:

Failing tests:
Encountered 2 failing tests in test/UniswapWithdrawHook.fork.1.t.sol:UniswapWithdrawHookTest
[FAIL. Reason: Expected call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de to be made 10 time(s), but was called 0 time(s) Counterexample: calldata=0x3d93c91a0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCall(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)
[FAIL. Reason: Expected call to 0x5991a2df15a8f6a256d3ec51e99254cd3fb576a9 with data 0x579073de to be made 10 time(s), but was called 0 time(s) Counterexample: calldata=0xc410223f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, args=[0, 0, 0, 0]] testFuzz_HookTest_withdrawTokenAndCallOnBehalf(uint256,uint256,uint256,uint256) (runs: 0, μ: 0, ~: 0)

The expected number of calls should actually be 1:
vm.expectCall( address(withdrawHook), abi.encodeWithSelector(withdrawHook.tokensWithdrawn.selector), **1**);
But this also fails with the error saying it was called 10 times.