fix(bootstrap): EXTRA_ARGS expansion produced phantom empty positional arg#3
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bootstrap.sh ended with:
ansible-playbook ... "${EXTRA_ARGS[@]:-}"
When EXTRA_ARGS=() (the no-`--` invocation, which is the documented
baseline path), `${arr[@]:-}` expands to a SINGLE empty-string
positional argument, not zero arguments. ansible-playbook receives
"" as a trailing positional, doesn't recognize it, and bails with
the unhelpful error 'unrecognized arguments:' (with empty space
after the colon -- the empty string is the bad arg).
The `:-` default form treats arrays the same as scalars: returns
the default string when null/empty. For arrays we want zero
positional args, not the default. The canonical safe form for
bash-3.2+ under `set -u` is:
${arr[@]+"${arr[@]}"}
which expands to nothing if the array is unset OR empty, and to
the array contents otherwise. Safe under `set -u` because
EXTRA_ARGS=() is always declared at the top of the script.
Verified with a mock ansible-playbook that prints argc + each
arg:
==== old broken behavior ====
argc=7
arg[6]=[--diff]
arg[7]=[] <-- phantom empty positional arg
==== fixed: empty EXTRA_ARGS ====
argc=6
arg[6]=[--diff] <-- no trailing arg
==== fixed: non-empty EXTRA_ARGS=(--check -vv) ====
argc=8
arg[6]=[--diff]
arg[7]=[--check]
arg[8]=[-vv]
Fixes #2.
This was referenced May 23, 2026
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What
Change the EXTRA_ARGS expansion in
bootstrap.shfrom"${EXTRA_ARGS[@]:-}"to${EXTRA_ARGS[@]+"${EXTRA_ARGS[@]}"}.Why
Fixes #2.
Surfaced bootstrapping a fresh Mac Studio on 2026-05-23. The
./bootstrap.shbaseline invocation (no--passthrough args) failedwith
ansible-playbook: error: unrecognized arguments:because the:-default form was passing a single empty-string positional toansible-playbook instead of zero args.
How
The
${arr[@]+"${arr[@]}"}pattern is bash-3.2+ canonical for'expand to nothing when array is empty, expand to contents
otherwise.' Safe under
set -ubecause EXTRA_ARGS is alwaysdeclared as
()at the top of the script.Behavior verified against a mock binary that echoes argc + each arg:
[](empty positional) -- bug--check -vv[--check] [-vv]Verification
Mock-bash tested locally. Real end-to-end via
./bootstrap.shon afresh Mac Studio happens immediately after merge.
Checklist
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