#!/bin/echo no
# TODO: categorize tests
# TODO https://mywiki.wooledge.org/BashFAQ
# http://tiswww.case.edu/php/chet/bash/FAQ
# https://mywiki.wooledge.org/BashPitfalls#set_-euo_pipefail
# // ${#} ${#x} ${#@} ${#x[@]} ${#!} ${!#}
# // ${!} ${!@} ${!@Q} ${!x} ${!x@} ${!x@Q} ${!x#} ${!x[} ${!x[*]}
# Looked like a prefix but wasn't: three chars (@ # -) are both paremeter name
# and slice operator. When immediately followed by } it's parameter, otherwise
# we did NOT have a prefix and it's an operator.
#
# ${#-} ${#-abc}
# ${##} ${##0}
# ${#@} ${#@Q}
#
# backslash not discarded: echo "abc\"def"
# ${x:-y} use default
# ${x:=y} assign default (error if positional)
# ${x:?y} err if null
# ${x:+y} alt value
# ${x:off} ${x:off:len} off<0 from end (must ": -"), len<0 also from end must
# 0-based indexing
# ${@:off:len} positional parameters, off -1 = len, -len is error
# 1-based indexing
# [] wins over +()
# touch 'AB[DEF]'; echo AB[+(DEF]) AB[+(DEF)?
# AB[+(DEF]) AB[DEF]
# Testing shell corner cases _within_ a shell script is kind of hard.
[ -f testing.sh ] && . testing.sh
# TODO make fake pty wrapper for test infrastructure
#testing "name" "command" "result" "infile" "stdin"
# texpect "name" "command" E/O/I"string"
# Use "bash" name for host, "sh" for toybox
[ -z "$SH" ] && { [ -z "$TEST_HOST" ] && SH="sh" || export SH="bash" ; }
# Prompt changes for root/normal user
[ $(id -u) -eq 0 ] && P='# ' || P='$ '
# run sufficiently isolated shell child process to get predictable results
SS="env -i PATH=${PATH@Q} PS1='\\$ ' $SH --noediting --noprofile --norc -is"
shxpect() {
X="$1"
shift
txpect "$X" "$SS" E"$P" "$@" X0
}
shxpect "prompt and exit" I$'exit\n'
shxpect "prompt and echo" I$'echo hello\n' O$'hello\n' E"$P"
shxpect "redirect err" I$'echo > /dev/full\n' E E"$P"
shxpect "wait for <(exit)" I$'cat <(echo hello 1>&2)\n' E$'hello\n' E"$P"
# Test the sh -c stuff before changing EVAL
testing '-c "" exit status 0' '$SH -c "" && echo $?' '0\n' '' ''
testing '-c args' "\$SH -c 'echo \$0,\$1,\$2,\$3' one two three four five" \
"one,two,three,four\n" "" ""
testing '-c args2' "\$SH -c 'echo \${10}' a b c d e f g h i j k l" "k\n" "" ""
testing '-c arg split' \
"$SH -c 'for i in a\"\$@\"b;do echo =\$i=;done;echo \$0' 123 456 789" \
"=a456=\n=789b=\n123\n" "" ""
testing '-c arg split2' \
"$SH -c 'for i in a\"\$* \$@\"b; do echo =\$i=;done' one two three four five"\
"=atwo three four five two=\n=three=\n=four=\n=fiveb=\n" "" ""
testing '-c arg count' "$SH -c 'echo \$#' 9 8 7 6 1 2 3 4" "7\n" "" ""
testing "exec3" '$C -c "{ exec readlink /proc/self/fd/0;} < /proc/self/exe"' \
"$(readlink -f $C)\n" "" ""
testing 'arg shift' "$SH -c '"'for i in "" 2 1 1 1; do echo $? $1; shift $i; done'"' one two three four five" \
"0 two\n0 three\n0 five\n0\n1\n" "" ""
testing '(subshell)' '$SH -c "(echo hello)"' 'hello\n' '' ''
testing 'syntax' '$SH -c "if true; then echo hello | fi" 2>/dev/null || echo x'\
'x\n' '' ''
# The bash man page is lying when it says $_ starts with an absolute path.
ln -s $(which $SH) bash
testing 'non-absolute $_' "./bash -c 'echo \$_'" './bash\n' '' ''
rm bash
testing 'exec exitval' "$SH -c 'exec echo hello' && echo \$?" "hello\n0\n" "" ""
testing 'simple script' '$SH input' 'input\n' 'echo $0' ''
testing 'simple script2' '$SH ./input two;echo $?' './input+two\n42\n' \
'\necho $0+$1\n\nexit 42' ''
testing '$LINENO 1' "$SH input" "1\n" 'echo $LINENO' ''
mkdir sub
echo echo hello > sub/script
testing 'simple script in $PATH' "PATH='$PWD/sub:$PATH' $SH script" \
'hello\n' '' ''
rm -rf sub
testing "script file" "chmod +x input; ./input" "hello\n" "#!$C\necho hello" ""
testing 'IFS $*' "$SH -c 'IFS=xy; echo \"\$*\"' one two tyree" "twoxtyree\n" \
"" ""
testing 'default exports' \
"env -i \"$(which $SH)\" --noprofile --norc -c env | sort" \
"PWD=$(pwd)\nSHLVL=1\n_=$(which env)\n" "" ""
testing "leading assignment fail" \
"{ \$SH -c 'X=\${a?blah} > walroid';ls walroid;} 2>/dev/null" '' '' ''
testing "lineno" "$SH input" "5 one\n6 one\n5 two\n6 two\n" \
'#!/bin/bash\n\nfor i in one two\ndo\n echo $LINENO $i\n echo $LINENO $i\ndone\n' ""
#########################################################################
# Change EVAL to call sh -c for us, using "bash" explicitly for the host.
export EVAL="$SH -c"
testing "smoketest" "echo hello" "hello\n" "" ""
testing "line break" $'ec\\\nho hello' 'hello\n' '' ''
testing "eval" "eval echo hello" "hello\n" "" ""
testing "eval2" "eval 'echo hello'; echo $?" "hello\n0\n" "" ""
testing "eval3" 'X="echo hello"; eval "$X"' "hello\n" "" ""
testing "eval4" 'eval printf '=%s=' \" hello \"' "= hello =" "" ""
NOSPACE=1 testing "eval5" 'eval echo \" hello \" | wc' ' 1 1 8' "" ""
testing "exec" "exec echo hello" "hello\n" "" ""
testing "exec2" "exec echo hello; echo $?" "hello\n" "" ""
# ; | && ||
testing "semicolon" "echo one;echo two" "one\ntwo\n" "" ""
testing "simple pipe" "echo hello | cat" "hello\n" "" ""
testing "&&" "true && echo hello" "hello\n" "" ""
testing "&&2" "false && echo hello" "" "" ""
testing "||" "true || echo hello" "" "" ""
testing "||2" "false || echo hello" "hello\n" "" ""
testing "&& ||" "true && false && potato || echo hello" "hello\n" "" ""
# redirection
testing "redir1" "cat < input" "hello\n" "hello\n" ""
testing "redir2" "echo blah >out; cat out" "blah\n" "" ""
testing "redir3" "echo more >>out; cat out" "blah\nmore\n" "" ""
testing "redir4" "touch /not/exist 2>out||grep -o /not/exist out" \
"/not/exist\n" "" ""
testing "redir5" "ls out /not/exist &> out2 || wc -l < out2" "2\n" "" ""
testing "redir6" "ls out /not/exist &>>-abc || wc -l < ./-abc" "2\n" "" ""
testing "redir7" "ls out /not/exist |& wc -l" "2\n" "" ""
testing "redir8" 'echo -n $( out 2>/does/not/exist\n' E E"$P" \
I$'wc -l < out\n' O$'0\n'
testing "redir10" 'echo hello 3<&3' "hello\n" "" ""
testing "redir11" 'if :;then echo one;fi {abc}A variable occurred
testing "expand" 'echo $PWD' "$(pwd)\n" "" ""
testing "expand2" 'echo "$PWD"' "$(pwd)\n" "" ""
testing "expand3" 'echo "$"PWD' '$PWD\n' "" ""
testing "expand4" 'P=x; echo "$P"WD' 'xWD\n' "" ""
testing "dequote" "echo one 'two' ''three 'fo'ur '\\'" \
'one two three four \\\n' '' ''
testing "leading variable assignment" 'abc=def env | grep ^abc=; echo $abc' \
"abc=def\n\n" "" ""
testing "leading variable assignments" \
"abc=def ghi=jkl env | egrep '^(abc|ghi)=' | sort; echo \$abc \$ghi" \
"abc=def\nghi=jkl\n\n" "" ""
testing "leading assignment occurs after parsing" \
'abc=def; abc=ghi echo $abc' "def\n" "" ""
testing "leading assignment space" 'X="abc def"; Y=$X; echo "$Y"' \
"abc def\n" "" ""
testing "leading assignment space2" \
'chicken() { X="$@"; }; chicken a b c d e; echo "$X"' 'a b c d e\n' '' ''
testing "leading assignment fail2" \
"{ 1blah=123 echo hello;} 2>/dev/null || echo no" "no\n" "" ""
testing "leading assignment redirect" \
"blah=123 echo hello > walrus && ls walrus" "walrus\n" "" ""
rm -f walrus
testing "{1..5}" "echo {1..5}" "1 2 3 4 5\n" "" ""
testing "{5..1}" "echo {5..1}" "5 4 3 2 1\n" "" ""
testing "{5..1..2}" "echo {5..1..2}" "5 3 1\n" "" ""
testing "{a..z..-3}" "echo {a..z..-3}" "a d g j m p s v y\n" "" ""
mkfifo POIT
testing 'background curly block' \
'{ sed s/ll/xx/ POIT; }& echo hello > POIT; wait' 'hexxo\n' '' ''
rm -f POIT
testing 'background pipe block' \
'if true; then { sleep .25;bzcat "$FILES"/blkid/ntfs.bz2; }& fi | wc -c' \
'8388608\n' '' ''
#$ IFS=x X=xyxz; for i in abc${X}def; do echo =$i=; done
#=abc=
#=y=
#=zdef=
testing "IFS whitespace before/after" \
'IFS=" x"; A=" x " B=" x" C="x " D=x E=" "; for i in $A $B $C $D L$A L$B L$C L$D $A= $B= $C= $D= L$A= L$B= L$C= L$D=; do echo -n {$i}; done' \
"{}{}{}{}{L}{L}{L}{L}{}{=}{}{=}{}{=}{}{=}{L}{=}{L}{=}{L}{=}{L}{=}" "" ""
testing "quotes and whitespace" \
'A=" abc def "; for i in ""$A""; do echo =$i=; done' \
"==\n=abc=\n=def=\n==\n" "" ""
testing "quotes and whitespace2" \
'A=" abc def "; for i in """"$A""; do echo =$i=; done' \
"==\n=abc=\n=def=\n==\n" "" ""
testing "quotes and whitespace3" \
'A=" abc def "; for i in ""x""$A""; do echo =$i=; done' \
"=x=\n=abc=\n=def=\n==\n" "" ""
testing "IFS" 'IFS=x; A=abx; echo -n "$A"' "abx" "" ""
testing "IFS2" 'IFS=x; A=abx; echo -n $A' "ab" "" ""
testing "IFS3" 'IFS=x; echo "$(echo abx)"' "abx\n" "" ""
testing "IFS4" 'IFS=x; echo $(echo abx)y' "ab y\n" "" ""
testing "IFS5" 'IFS=xy; for i in abcxdefyghi; do echo =$i=; done' \
"=abc def ghi=\n" "" ""
testing 'empty $! is blank' 'echo $!' "\n" "" ""
testing '$! = jobs -p' 'true & [ $(jobs -p) = $! ] && echo yes' "yes\n" "" ""
testing '$*' 'cc(){ for i in $*;do echo =$i=;done;};cc "" "" "" "" ""' \
"" "" ""
testing '$*2' 'cc(){ for i in "$*";do echo =$i=;done;};cc ""' \
"==\n" "" ""
testing '$*3... Flame. Flames. Flames, on the side of my face...' \
'cc(){ for i in "$*";do echo =$i=;done;};cc "" ""' "= =\n" "" ""
testing 'why... oh.' \
'cc() { echo ="$*"=; for i in =$*=; do echo -$i-; done;}; cc "" ""; echo and; cc ""' \
'= =\n-=-\n-=-\nand\n==\n-==-\n' "" ""
testing 'really?' 'cc() { for i in $*; do echo -$i-; done;}; cc "" "" ""' \
"" "" ""
testing 'Sigh.' 'cc() { echo =$1$2=;}; cc "" ""' "==\n" "" ""
testing '$*4' 'cc(){ for i in "$*";do echo =$i=;done;};cc "" "" "" "" ""' \
"= =\n" "" ""
testing '$*5' 'cc(){ for i in "$*";do echo =$i=;done;};cc "" "abc" ""' \
"= abc =\n" "" ""
# creating empty arguments without quotes
testing '$* + IFS' \
'IFS=x; cc(){ for i in $*; do echo =$i=;done;};cc xabcxx' \
"==\n=abc=\n==\n" "" ""
testing '$@' 'cc(){ for i in "$@";do echo =$i=;done;};cc "" "" "" "" ""' \
"==\n==\n==\n==\n==\n" "" ""
testing "IFS10" 'IFS=bcd; A=abcde; for i in $A; do echo =$i=; done' \
"=a=\n==\n==\n=e=\n" "" ""
testing "IFS11" \
'IFS=x; chicken() { for i in $@$@; do echo =$i=; done;}; chicken one "" abc dxf ghi' \
"=one=\n==\n=abc=\n=d=\n=f=\n=ghione=\n==\n=abc=\n=d=\n=f=\n=ghi=\n" "" ""
testing "IFS12" 'IFS=3;chicken(){ return 3;}; chicken;echo 3$?3' '3 3\n' "" ""
testing "IFS combinations" \
'IFS=" x"; A=" x " B=" x" C="x " D=x E=" "; for i in $A $B $C $D L$A L$B L$C L$D $A= $B= $C= $D= L$A= L$B= L$C= L$D=; do echo -n {$i}; done' \
"{}{}{}{}{L}{L}{L}{L}{}{=}{}{=}{}{=}{}{=}{L}{=}{L}{=}{L}{=}{L}{=}" "" ""
testing "! isn't special" "echo !" "!\n" "" ""
testing "! by itself" '!; echo $?' "1\n" "" ""
testing "! true" '! true; echo $?' "1\n" "" ""
testing "! ! true" '! ! true; echo $?' "0\n" "" ""
testing "! syntax err" '! echo 2>/dev/null < doesnotexist; echo $?' "0\n" "" ""
# The bash man page doesn't say quote removal here, and yet:
testing "case quoting" 'case a in "a") echo hello;; esac' 'hello\n' "" ""
testing "subshell splitting" 'for i in $(true); do echo =$i=; done' "" "" ""
#testing "subshell split 2"
# variable assignment argument splitting only performed for "$@"
testing "assignment nosplit" 'X="one two"; Y=$X; echo $Y' "one two\n" "" ""
testing "argument splitting" \
'chicken() { for i in a"$@"b;do echo =$i=;done;}; chicken 123 456 789' \
"=a123=\n=456=\n=789b=\n" "" ""
testing "assignment nosplit2" 'pop(){ X="$@";};pop one two three; echo $X' \
"one two three\n" "" ""
#testing "leading assignments don't affect current line" \
# 'VAR=12345 echo ${VAR}a' "a\n" "" ""
#testing "can't have space before first : but yes around arguments" \
# 'BLAH=abcdefghi; echo ${BLAH: 1 : 3 }' "bcd\n" "" ""
testing "subshell exit err" '(exit 42); echo $?' "42\n" "" ""
# Same thing twice, but how do we cmp if exec exited?
#testing 'exec and $$' testing 'echo $$;exec readlink /proc/self'
X="$(realpath $(which readlink))"
testing "exec in paren" \
'(exec readlink /proc/self/exe);echo hello' "$X\nhello\n" "" ""
testing "exec in brackets" \
"{ exec readlink /proc/self/exe;};echo hi" "$X\n" "" ""
NOSPACE=1 testing "curly brackets and pipe" \
'{ echo one; echo two ; } | tee blah.txt; wc blah.txt' \
"one\ntwo\n2 2 8 blah.txt\n" "" ""
NOSPACE=1 testing "parentheses and pipe" \
'(echo two;echo three)|tee blah.txt;wc blah.txt' \
"two\nthree\n2 2 10 blah.txt\n" "" ""
testing "pipe into parentheses" \
'echo hello | (read i /dev/null; echo $abc' \
"\n" '' ''
testing '${@:3:5}' 'chicken() { for i in "${@:3:5}"; do echo =$i=; done; } ; chicken ab cd ef gh ij kl mn op qr' \
'=ef=\n=gh=\n=ij=\n=kl=\n=mn=\n' '' ''
testing '${@:3:5}' 'chicken() { for i in "${*:3:5}"; do unset IFS; echo =$i=; done; } ; IFS=x chicken ab cd ef gh ij kl mn op qr' \
'=efxghxijxklxmn=\n' '' ''
testing 'sequence check' 'IFS=x; X=abxcd; echo ${X/bxc/g}' 'agd\n' '' ''
# TODO: The txpect plumbing does not work right yet even on TEST_HOST
#txpect "backtick0" "$SS" "E$P" 'IX=fred; echo `echo \\\\$x`'$'\n' 'Ofred' "E$P" X0
#txpect "backtick1" "$SS" "E$P" 'IX=fred; echo `echo $x`'$'\n' 'Ofred'$'\n' "E$P" X0
#txpect "backtick2" "$SS" "E$P" 'IX=fred; echo `x=y; echo $x`' $'Oy\n' "E$P" X0
shxpect '${ with newline' I$'HELLO=abc; echo ${HELLO/b/\n' E"> " I$'}\n' O$'a c\n'
shxpect 'here1' I$'POTATO=123; cat << EOF\n' E"> " \
I$'$POTATO\n' E"> " I$'EOF\n' O$'123\n'
shxpect 'here2' I$'POTATO=123; cat << E"O"F\n' E"> " \
I$'$POTATO\n' E"> " I$'EOF\n' O$'$POTATO\n'
testing 'here3' 'abc(){ cat <<< x"$@"yz;};abc one two "three four"' \
"xone two three fouryz\n" "" ""
testing '${var}' 'X=abcdef; echo ${X}' 'abcdef\n' '' ''
testing '${#}' 'X=abcdef; echo ${#X}' "6\n" "" ""
testing 'empty ${}' '{ echo ${};} 2>&1 | grep -o bad' 'bad\n' '' ''
shxpect 'empty ${} syntax err abort' I$'echo ${}; echo hello\n' \
E I$'echo and\n' O$'and\n'
testing '${$b}' '{ echo ${$b};} 2>&1 | grep -o bad' 'bad\n' '' ''
testing '${!PATH*}' 'echo ${!PATH*}' 'PATH\n' '' ''
testing '${!PATH@}' 'echo ${!PATH@}' 'PATH\n' '' ''
#testing '${!PATH[@]}' 'echo ${!PATH[@]}' '0\n' '' ''
testing '${!x}' 'X=abcdef Y=X; echo ${!Y}' 'abcdef\n' '' ''
testing '${!x@}' 'ABC=def; def=ghi; echo ${!ABC@}' 'ABC\n' '' ''
testing '${!x} err' '{ X=abcdef Y=X:2; echo ${!Y}; echo bang;} 2>/dev/null' \
'' '' ''
testing '${!x*}' 'abcdef=1 abc=2 abcq=; echo "${!abc@}" | tr " " \\n | sort' \
'abc\nabcdef\nabcq\n' '' ''
testing '${!x*} none' 'echo "${!abc*}"' '\n' '' ''
testing '${!x*} err' '{ echo "${!abc*x}"; echo boing;} 2>/dev/null' '' '' ''
testing '${!none@Q}' 'echo ${X@Q} ${!X@Q}; X=ABC; echo ${!X@Q}' '\n\n' '' ''
testing '${!x@Q}' 'ABC=123 X=ABC; echo ${!X@Q}' "'123'\n" '' ''
testing '${#@Q}' 'echo ${#@Q}' "'0'\n" '' ''
testing '${!*}' 'xx() { echo ${!*};}; fruit=123; xx fruit' '123\n' '' ''
testing '${!*} indirect' 'xx() { echo ${!a@Q};}; a=@; xx one two three' \
"'one' 'two' 'three'\n" '' ''
testing '${!x@ } match' \
'{ ABC=def; def=ghi; echo ${!ABC@ }; } 2>&1 | grep -o bad' 'bad\n' '' ''
testing '${!x@ } no match no err' 'echo ${!ABC@ }def' 'def\n' '' ''
testing '${!x@ } no match no err2' 'ABC=def; echo ${!ABC@ }ghi' 'ghi\n' '' ''
toyonly testing '${#x::}' 'ABC=abcdefghijklmno; echo ${#ABC:1:2}' '5\n' '' ''
# TODO: ${!abc@x} does _not_ error? And ${PWD@q}
testing '$""' 'ABC=def; echo $"$ABC"' 'def\n' '' ''
testing '"$""" does not nest' 'echo "$"abc""' '$abc\n' '' ''
testing '${\}}' 'ABC=ab}cd; echo ${ABC/\}/x}' 'abxcd\n' '' ''
testing 'bad ${^}' '{ echo ${^};} 2>&1 | grep -o bad' 'bad\n' '' ''
testing '${:}' 'ABC=def; echo ${ABC:1}' 'ef\n' '' ''
testing '${a: }' 'ABC=def; echo ${ABC: 1}' 'ef\n' '' ''
testing '${a :}' 'ABC=def; { echo ${ABC :1};} 2>&1 | grep -o bad' 'bad\n' '' ''
testing '${::}' 'ABC=defghi; echo ${ABC:1:2}' 'ef\n' '' ''
testing '${: : }' 'ABC=defghi; echo ${ABC: 1 : 2 }' 'ef\n' '' ''
testing '${::} indirect' 'ABC=defghi:1:2; { echo ${!ABC};} 2>&1 | grep -o bad' \
'bad\n' '' ''
testing '${::-}' 'ABC=defghi; echo ${ABC:1:-2}' 'efg\n' '' ''
testing '${:-:-}' 'ABC=defghi; echo ${ABC:-3:2}' 'defghi\n' '' ''
testing '${:-:-}2' 'echo ${ABC:-3:2}' '3:2\n' '' ''
testing '${: -:}' 'ABC=defghi; echo ${ABC: -3:2}' 'gh\n' '' ''
testing '${@%}' 'chicken() { for i in "${@%abc}"; do echo "=$i="; done;}; chicken 1abc 2abc 3abc' '=1=\n=2=\n=3=\n' '' ''
testing '${*%}' 'chicken() { for i in "${*%abc}"; do echo "=$i="; done;}; chicken 1abc 2abc 3abc' '=1 2 3=\n' '' ''
testing '${@@Q}' 'xx() { echo "${@@Q}"; }; xx one two three' \
"'one' 'two' 'three'\n" '' ''
shxpect '${/newline/}' I$'x=$\'\na\';echo ${x/\n' E'> ' I$'/b}\n' O$'ba\n' E'> '
shxpect 'line continuation' I$'echo "hello" \\\n' E'> ' I$'> blah\n' E"$P" \
I$'wc blah\n' O$'1 1 6 blah\n'
shxpect 'line continuation2' I$'echo ABC\\\n' E'> ' I$'DEF\n' O$'ABCDEF\n'
# Race condition (in bash, but not in toysh) can say 43.
testing 'SECONDS' 'readonly SECONDS=41; sleep 1; echo $SECONDS' '42\n' '' ''
# testing 'SECONDS2' 'readonly SECONDS; SECONDS=0; echo $SECONDS' '' '' '' #bash!
testing 'SECONDS2' 'SECONDS=123+456; echo $SECONDS' '0\n' '' '' #bash!!
testing '$LINENO 2' $'echo $LINENO\necho $LINENO' '0\n1\n' '' ''
testing '$EUID' 'echo $EUID' "$(id -u)\n" '' ''
testing '$UID' 'echo $UID' "$(id -ur)\n" '' ''
testing 'readonly leading assignment' \
'{ readonly abc=123;abc=def echo hello; echo $?;} 2>output; grep -o readonly output' \
'hello\n0\nreadonly\n' '' ''
testing 'readonly leading assignment2' \
'readonly boink=123; export boink; { boink=234 env | grep ^boink=;} 2>/dev/null; echo $?' 'boink=123\n0\n' '' ''
testing 'readonly for' \
'readonly i; for i in one two three; do echo $i; done 2>/dev/null; echo $?' \
'1\n' '' ''
testing 'readonly {}<' \
'readonly i; echo hello 2>/dev/null {i}/dev/null\n' O$'two\n' E$'+ echo two\n'"$P" \
I$'{ echo three; } 2>/dev/null\n' O$'three\n' E"$P"
testing 'source file' 'source input' 'hello\n' 'echo hello \\\n' ''
testing '. file' '. input' 'hello\n' 'echo hello \\\n' ''
testing 'source no newline' 'source input' 'hello \\\n' 'echo hello \\' ''
# TODO finish variable list from shell init
# $# $? $- $$ $! $0
# always exported: PWD SHLVL _
# ./bash -c 'echo $_' prints $BASH, but PATH search shows path? Hmmm...
# ro: UID PPID EUID $
# IFS LINENO
# PATH HOME SHELL USER LOGNAME SHLVL HOSTNAME HOSTTYPE MACHTYPE OSTYPE OLDPWD
# PS0 PS1='$ ' PS2='> ' PS3 PS4 BASH BASH_VERSION
# ENV - if [ -n "$ENV" ]; then . "$ENV"; fi # BASH_ENV - synonym for ENV
# FUNCNEST - maximum function nesting level (abort when above)
# REPLY - set by input with no args
# OPTARG OPTIND - set by getopts builtin
# OPTERR
# maybe not: EXECIGNORE, FIGNORE, GLOBIGNORE
#BASHPID - synonym for $$ HERE
#BASH_SUBSHELL - SHLVL synonym
#BASH_EXECUTION_STRING - -c argument
#
#automatically set:
#OPTARG - set by getopts builtin
#OPTIND - set by getopts builtin
#
#PROMPT_COMMAND PROMPT_DIRTRIM PS0 PS1 PS2 PS3 PS4
#
#unsettable (assignments ignored before then)
#LINENO SECONDS RANDOM
#GROUPS - id -g
#HISTCMD - history number
#
#TMOUT - used by read
# does not match: ./sh -c 'echo {a..Z}' becomes a ` _ ^ ] \ [ Z
# commit ec6639407b9e
#- IS_TOYBOX_RE='(toybox|This is not GNU).*'
#- [[ "$IS_TOYBOX" =~ $IS_TOYBOX_RE ]] || SKIPNEXT=1
#+ case "$IS_TOYBOX" in
#+ toybox*) ;;
#+ This\ is\ not\ GNU*) ;;
#+ *) SKIPNEXT=1 ;;
#+ esac