failures=0

check() {
	if ! eval "[ $* ]"; then
		echo "Failed: $*"
		: $((failures += 1))
	fi
}

check '`echo /et[c]/` = "/etc/"'
check '`printf /var/empty%s /et[c]/` = "/var/empty/etc/"'
check '"`echo /et[c]/`" = "/etc/"'
check '`echo "/et[c]/"` = "/etc/"'
check '`printf /var/empty%s "/et[c]/"` = "/var/empty/et[c]/"'
check '`printf /var/empty/%s \"/et[c]/\"` = "/var/empty/\"/et[c]/\""'
check '"`echo \"/et[c]/\"`" = "/et[c]/"'
check '"`echo "/et[c]/"`" = "/et[c]/"'
check '`echo $$` = $$'
check '"`echo $$`" = $$'
check '`echo \$\$` = $$'
check '"`echo \$\$`" = $$'

# Command substitutions consisting of a single builtin may be treated
# differently.
check '`:; echo /et[c]/` = "/etc/"'
check '`:; printf /var/empty%s /et[c]/` = "/var/empty/etc/"'
check '"`:; echo /et[c]/`" = "/etc/"'
check '`:; echo "/et[c]/"` = "/etc/"'
check '`:; printf /var/empty%s "/et[c]/"` = "/var/empty/et[c]/"'
check '`:; printf /var/empty/%s \"/et[c]/\"` = "/var/empty/\"/et[c]/\""'
check '"`:; echo \"/et[c]/\"`" = "/et[c]/"'
check '"`:; echo "/et[c]/"`" = "/et[c]/"'
check '`:; echo $$` = $$'
check '"`:; echo $$`" = $$'
check '`:; echo \$\$` = $$'
check '"`:; echo \$\$`" = $$'

check '`set -f; echo /et[c]/` = "/etc/"'
check '"`set -f; echo /et[c]/`" = "/et[c]/"'

exit $((failures > 0))