Error message during macOS / Darwin install: ldd: command not found

[sumbach]

During chezmoi installation on macOS, I see the following disconcerting (but ultimately harmless?) message:

$ asdf install chezmoi latest
/Users/samumbach/.asdf/plugins/chezmoi/lib/utils.bash: line 54: ldd: command not found
* Downloading chezmoi release 2.42.0...
chezmoi 2.42.0 installation was successful!

$ uname -a
Darwin macbach-pro 16.7.0 Darwin Kernel Version 16.7.0: Sun Jun  2 20:26:31 PDT 2019; root:xnu-3789.73.50~1/RELEASE_X86_64 x86_64

This appears to be related to the detect_variant() function added for musl libc; see also:

• Fails to detect correct Linux version to install if environment does not use GLIBC but uses alternative #34
• Github Release not found at Alpine based Container #39

I can see two potentially simple fixes:

1. Discard all stderr from ldd (which will hide this error, but may obscure other potentially useful error output).
2. Explicitly detect when ldd is present; assume -musl variant is not necessary when ldd missing.

I'll open a branch/PR for latter, but please let me know if you'd rather go with the first.

Thanks for the plugin @joke !!! 😄