Build error invalid value with Library function that returns Enum

[neodaoist]

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 (950d863 2023-10-25T11:49:42.980532000Z)

What command(s) is the bug in?

forge build

Operating System

macOS (Apple Silicon)

Describe the bug

I'm encountering the following build error, when using an Enum as a return variable from a function inside a Library. The included code example is enough to reproduce on my machine.

Build error:

invalid value: string "LibCounter.TestEnum", expected a valid Solidity type specifier at line 1 column 169

Code example:

// SPDX-License-Identifier: UNLICENSED
pragma solidity 0.8.21;

library LibCounter {
    enum TestEnum {
        NO,
        YES
    }

    function sayYes() external pure returns (TestEnum) {
        return TestEnum.YES;
    }
}