Example Project ./setup.sh: line 38: MISE_ARGS[@]: unbound variable

[devahmedshendy]

When I run setup script on macOS, I get this error:

 ./setup.sh: line 38: MISE_ARGS[@]: unbound variable 

I figured out that this error only happens in older versions of bash (mine is 3.2.57, which is the macOS default system Bash).

I tried following reproduction script:

#!/usr/bin/env bash
set -u

# Declare an empty array
MISE_ARGS=()

echo "Testing array expansion..."
echo "Arguments: ${MISE_ARGS[@]}" 
echo "Success! No error occurred."

It fails with an error on my Bash 3.2.57, but works on newer versions (e.g., Bash 5.x).

Is it a requirement to have newer bash version so I - somehow - install and manage newer versions of bash.
Or this requires setup.sh to provide backward compatibility? it just needs to be from "${MISE_ARGS[@]}" to ${MISE_ARGS[@]+"${MISE_ARGS[@]}"}

[Kyle-Ye]

Thanks for the report and the detailed reproduction.

You're right: this comes from Bash 3.2 treating an empty array expansion as an unbound variable when set -u is enabled. The setup script should work with macOS' system Bash (My local bash is 5.x installed by homebrew), so I prepared a small fix that avoids expanding MISE_ARGS when it is empty while preserving the --compute path.

I verified it with /bin/bash 3.2 and a newer Bash using both the default and --compute flows, plus shellcheck. I'll open a PR for it shortly.