(Feature request) Provide missing stack trace depth

[webthethird]

Component

Forge

Describe the feature you would like

I have noticed that the stack traces provided for failing tests only include top-level calls from my test contract, and are missing any external calls that occur while executing the top-level call, which normally are included when using vanilla foundry. For example, I have the following contracts and test:

contract A {
    function revertIfEven(uint256 number) public pure returns (uint256) {
        if (number % 2 == 0) {
            revert("Number is even");
        }
        return number;
    }
}

contract B {
    A public a;

    constructor(A _a) {
        a = _a;
    }

    function callRevertIfEven(uint256 number) public view returns (uint256) {
        return a.revertIfEven(number);
    }
}

contract C {
    B public b;

    constructor(B _b) {
        b = _b;
    }

    function isEven(uint256 number) public view returns (bool) {
        try b.callRevertIfEven(number) {
            return false;
        } catch Error(string memory) {
            return true;
        }
    }
}

contract ABCTest is Test {
    A public a;
    B public b;
    C public c;

    function setUp() public {
        a = new A();
        b = new B(a);
        c = new C(b);
    }

    function test_StackTraceDepth() public {
        // Call C.isEven, which calls B.callRevertIfEven, which calls A.revertIfEven
        c.isEven(2);
        // Force test to fail so we can see the stack trace
        assertTrue(false);
    }
}

When this test fails, we can observe the following stack trace (after replacing addresses with contract names):

Ran 1 test for test/ABC.t.sol:ABCTest
[FAIL. Reason: assertion failed] test_StackTraceDepth() (gas: 8097)
Traces:
  [8097] ABCTest::test_StackTraceDepth()
    ├─ [0] C::isEven(2) [staticcall]
    │   └─ ← true
    ├─ [0] VM::assertTrue(false) [staticcall]
    │   └─ ← assertion failed
    └─ ← assertion failed

But I would expect the stack trace to look like this:

Ran 1 test for test/ABC.t.sol:ABCTest
[FAIL. Reason: assertion failed] test_StackTraceDepth() (gas: 8097)
Traces:
  [8097] ABCTest::test_StackTraceDepth()
    ├─ [0] C::isEven(2) [staticcall]
    |   ├─ [0] B::callRevertIfEven(2) [staticcall]
    |   |   ├─ [0] A::revertIfEven(2) [staticcall]
    |   |   |   └─ ← revert
    |   |   └─ ← revert
    │   └─ ← true
    ├─ [0] VM::assertTrue(false) [staticcall]
    │   └─ ← assertion failed
    └─ ← assertion failed

Additional context

Minimal reproducible example:
https://github.com/webthethird/min-reproducible-missing-stack-trace-depth

[dutterbutter]

Thank you very much for the feature request and even bigger thanks for the minimal reproducible example! We will definitely look into this!

[webthethird]

@dutterbutter any idea when this might be implemented? It would really help me with debugging an odd issue I'm encountering in my tests!