. "$BST_LIB"
require dash dash/present

# basic command execution via -c (runs in the shell process, no fork/exec)
check_out dash/echo "hello" dash -c 'echo hello'

# POSIX arithmetic expansion
check_out dash/arith "42" dash -c 'echo $((6 * 7))'

# POSIX parameter expansion (prefix strip)
check_out dash/param "def" dash -c 'x=abcdef; echo ${x#abc}'

# control flow: for-loop counting
check_out dash/loop "4" dash -c 'n=0; for i in a b c d; do n=$((n+1)); done; echo $n'

# exit-status propagation (dash signals via rc, so assert on rc directly)
check_rc dash/exit 3 dash -c 'exit 3'

# executes a real script file, not just -c: while-loop to a fixed count
tmp=${TMPDIR:-/tmp}/bst-dash.$$
printf '%s\n' '#!/bin/dash' 'i=0' 'while [ $i -lt 5 ]; do i=$((i+1)); done' 'echo done=$i' > "$tmp.sh" 2>/dev/null
check_out dash/scriptfile "done=5" dash "$tmp.sh"
rm -f "$tmp.sh"