[Bug] Installation fails on Linux due to macOS-specific dependency (pyobjc-framework-Quartz)

[CongJie-Pan]

Describe the bug

When attempting to install the gum package on a Linux environment (Ubuntu) using pip install git+https://github.com/GeneralUserModels/gum.git, the installation fails.

The error occurs because the setup configuration strictly depends on pyobjc-framework-Quartz, which is a macOS-only library. This causes the installer to look for the /usr/bin/sw_vers command, leading to a FileNotFoundError.

To Reproduce

1. Use a Linux machine (e.g., Ubuntu).
2. Run the command: pip install git+https://github.com/GeneralUserModels/gum.git
3. See error.

Error Output

Getting requirements to build wheel ... error
error: subprocess-exited-with-error

subprocess.check_output(["/usr/bin/sw_vers", "-productVersion"])
FileNotFoundError: [Errno 2] No such file or directory: '/usr/bin/sw_vers'

Expected behavior

The package should install successfully on Linux. The pyobjc dependency should ideally be conditionally required only for macOS environments (e.g., pyobjc-framework-Quartz; sys_platform == 'darwin').

Workaround Used

I was able to successfully install the package by cloning the repository and manually removing pyobjc from the dependency files (pyproject.toml / setup.py) before running pip install -e ..

Environment

• OS: Linux (Ubuntu)
• Python Version: 3.11 (or specify your exact version)