[Toybox] Shell tests for reference.
Rob Landley
rob at landley.net
Mon Dec 16 21:12:54 PST 2019
For those of you following my shell struggles at https://landley.net/notes.html
here's what one of my shell test files looks like. I doubt this
makes any sense to anyone other than me.
Sorry it's been so quiet on here. I got my blog caught up, and am ruminating
about shell stuff there instead. :)
Rob
/*
alias bg cd command fc fg getopts hash jobs kill read type ulimit umask unalias
wait exit if while for case export set unset trap exec function source
TOY_MAYFORK: echo test printf
no memory allocations, filehandles open... if signaled, no cleanup.
maybe: help ulimit
.toysh_history file
{abc,def}
$LINENO $RANDOM
"source" and "." check current dir after $PATH
job control: CTRL-Z, CTRL-C, fg, bg, kill %jobspec, wait
$(command)
$((math)) # integer attribute for variables, assignment does that
$((abc"def)) the " doesn't take effect so )) is recognized?
if then elif else fi
for while until do done
case esac
function () { commands ; }
local variables in functions
set -x (and -x command line option) to trace
export -n (unexports)
readonly
read set unset umask
time (whole pipeline)
command trap type times getopts
todo: echo | (cat) # as far as cat's concerned previous end was NULL
What to do about builtin vs $PATH:
check $PATH first _then_ builtin?
config opt?
if files exist use 'em, otherwise:
/dev/fd/fd stdin stdout stderr tcp/host/port udp/host/port
exec redirects in current shell
n<word
n>word
n>>word (append)
&>word # stdout and stderr, same as >word 2>&1
&>>word (append)
>&word # note: >&$BLAH when $BLAH is number or -
n<&word # number = duplicate, - = close, number- = move
n>&word # special case: no n and word not number or -, redirect stderr & out.
n<<word # only quote removal, no expansion
# unquoted: parameter ex, command subst, arith ex, \\ \$ \` \newline
<<-word # strips leading tabs
<<<word # all expansions _except_ pathname expansion and word splitting
n<>word # open file word for reading & writing, create if necessary, n def 0
// &> or >& = >word 2>&1
// &>> append stdout & stderr == >> word 2>&1
// <&# copy input fd (error if # not open for read)
// >&# copy output fd (error if # not open for write)
// <&#- move fd# to n
// >&#- move fd# to n
What does this mean?
env {abcdef}>&2 | grep abcdef
Instead of number, precede with {varname}?
brace expansion, tilde expansion, parameter and variable expansion,
command substitution,
arithmetic expansion, quote removal, pathname expansion, and word
splitting.
<< no path ex or word split
test should work as a nofork, handle [[
what does $(( ))
handle ( ( echo hello ) ) | cat and (echo)|cat
if (then)
else elif (then)
fi
for select while until (do)
done
case (esac)
( )
{ }
[[ ]]
}
// function
// HERE document
// ( ) - ) is always last argument of line
// | & && || |&
// "if", "for", "while", "until", "select"
// "do" : "then";
// then else elif fi
// continue break case esac return do done function
// in time { } ]] ]]
// ! coproc
// function ()
// . source [ test [[ ( { ((
// [ pwd ulimit -- kill time
// cd exit -- pushd popd logout umask getopts eval exec
// fg bg jobs disown wait suspend
// alias unalias set export unset let local readonly read shift trap
# Because of HERE documents we can't re-parse, have to retain state.
# -- either that or our caller has to know about here document servicing?
# -c input must be split into lines for HERE documents
< > >> <<< WORD
<< HERE [HERE] # eat lines until HERE as _only_ word on line
if [then]
for while until select [do]
case [esac]
( [)] # funky because ) not first word
{ [}]
[[ []]]
function NAME ( ) { # note expect { doesn't eat { be because need to expect }
*/
# can't have space before first : but arguments can have lead/trail
$ BLAH=abcdefghi; echo ${BLAH: 1 : 3 }
# leading assignments don't affect current command line
$ VAR=12345 echo $VARa
$ bash -c 'ls $('
bash: -c: line 0: unexpected EOF while looking for matching `)'
bash: -c: line 1: syntax error: unexpected end of file
$ ;
bash: syntax error near unexpected token `;'
$ ABC= ; env | grep ABC= ; unset ABC ; env | grep ABC=
ABC=
$ cat blah<(echo hello)thing
cat: blah/dev/fd/63thing: No such file or directory
$ "AB"="CD" echo $AB
bash: AB=CD: command not found
landley at driftwood:~/toybox/toybox$ AB="CD" echo $AB
$ 'AB'="CD" echo $AB
bash: AB=CD: command not found
$ \AB="CD" echo $AB
bash: AB=CD: command not found
$ \AB="CD" echo $AB
$ if echo hello; then fi
bash: syntax error near unexpected token `fi'
$ echo )
bash: syntax error near unexpected token `)'
$ ( echo hello ) | cat
hello
$ if
> true
> then
> echo hello
> fi
hello
$ if true; then echo hello; fi
hello
$ if false; then echo hello; fi
$ false; X=47; echo $?
0
$ if;
bash: syntax error near unexpected token `;'
$ if
> true
> echo
> hello
> fi
bash: syntax error near unexpected token `fi'
$ echo )))
bash: syntax error near unexpected token `)'
$ echo &&&
bash: syntax error near unexpected token `&'
$ echo |||
bash: syntax error near unexpected token `|'
$ echo hello | if true; then read i; echo i=$i; fi
i=hello
$ if true && false; then echo hi; fi
while true ; do echo hello; done | tee blah
if { echo hello; }; then echo hi; fi
if if true; then true; fi; then echo hello; fi
boom(){ echo hello; }; boom
( ( echo; thingy ) ) | cat
$ echo hello | X=y env | grep -w X; echo $X
X=y
;|x
;x|
(echo)also
(echo)(echo)
$ if true esac; then echo hi; fi
hi
# note: exits top level shell anyway!
$ (exit walrus)
bash: exit: walrus: numeric argument required
$ echo $?
2
$ exit walrus 2>blah.txt
$ echo ${abc:?error m essage}
bash: abc: error m essage
$ if blah () { echo bang; true; }; blah; then echo hello; fi; blah
bang
hello
bang
$ meep() { echo hello; klarg () { echo helloier; }; klarg; }
$ meep
hello
helloier
$ meep() { echo hello; klarg() { echo helloier; } ; }
$ klarg
bash: klarg: command not found
$ meep
hello
$ klarg
helloier
$
landley at driftwood:~/toybox/toybox$ thingy ()
> ^C
landley at driftwood:~/toybox/toybox$ echo (
bash: syntax error near unexpected token `newline'
landley at driftwood:~/toybox/toybox$ function
bash: syntax error near unexpected token `newline'
landley at driftwood:~/toybox/toybox$ function name () {
> }
bash: syntax error near unexpected token `}'
landley at driftwood:~/toybox/toybox$ function name () { ;}
bash: syntax error near unexpected token `;'
landley at driftwood:~/toybox/toybox$ if ; then; echo hello; fi
bash: syntax error near unexpected token `;'
landley at driftwood:~/toybox/toybox$ func (); { echo hello; }
bash: syntax error near unexpected token `;'
$ if true |
> then
bash: syntax error
echo one && if true; then echo hello; fi
one
hello
$ echo one two \
> three
$ bash -c "$(echo -e 'cat << HERE\none two\nHERE')"
one two
$ cat << HERE; echo hello
> boing
> HERE
boing
hello
$ cat << one << two
> abc
$ ls > file 2>&1 #redirects both
$ ls 2>&1 >file # redirects only stdout, stderr goes to original stdout
$ echo hello < nowhere
bash: nowhere: No such file or directory
$ cat << E"O"F
> $PATH
> EOF
$PATH
$ cat << HERE filename
> HERE
cat: filename: No such file or directory
$ cat <<< here filename
cat: filename: No such file or directory
landley at driftwood:~/toybox/toybox$ bash -c "cat <<< HERE; echo hello; HERE"
HERE
hello
bash: HERE: command not found
landley at driftwood:~/toybox/toybox$ bash -c "cat << HERE; echo hello; HERE"
bash: warning: here-document at line 0 delimited by end-of-file (wanted `HERE')
hello
bash: HERE: command not found
landley at driftwood:~/toybox/toybox$ bash -c "$(echo 'cat << HERE\necho hello\nHERE')"
bash: warning: here-document at line 0 delimited by end-of-file (wanted `HEREnecho')
cat: hellonHERE: No such file or directory
landley at driftwood:~/toybox/toybox$ bash -c "$(echo -e 'cat << HERE\necho
hello\nHERE')"
echo hello
landley at driftwood:~/toybox/toybox$ X=3; echo $((X))
3
landley at driftwood:~/toybox/toybox$ X=3; echo $((X))^C
landley at driftwood:~/toybox/toybox$ echo |
>
> cat
landley at driftwood:~/toybox/toybox$ echo &&
> &&
bash: syntax error near unexpected token `&&'
landley at driftwood:~/toybox/toybox$ echo &&
> ;
bash: syntax error near unexpected token `;'
landley at driftwood:~/toybox/toybox$ if
> true
> then
> echo hello
> fi
hello
landley at driftwood:~/toybox/toybox$ << EOF
> echo hello
> EOF
$ echo &<2
[1] 17850
bash: 2: No such file or directory
landley at driftwood:~/toybox/toybox$
[1]+ Done echo
landley at driftwood:~/toybox/toybox$ { echo hello; }
hello
landley at driftwood:~/toybox/toybox$ { { echo hello; };}
hello
landley at driftwood:~/toybox/toybox$ {{ echo hello; };}
bash: syntax error near unexpected token `}'
landley at driftwood:~/toybox/toybox$ { {echo hello; };}
bash: syntax error near unexpected token `}'
landley at driftwood:~/toybox/toybox$ { { echo hello; };}
hello
landley at driftwood:~/toybox/toybox$ {
> {
> echo hello
> }
> }
hello
$ if cat << EOF ; then
> one two three
> EOF
> echo hello
> fi
one two three
hello
cat <(ls "$PWD"/a{b,c}*) &> /dev/tcp/127.0.0.1/80
$ while grep -q << EOF walrus; do
> walrus
> EOF
> echo hello; done | head -n 3
hello
hello
hello
$ if echo hello; then echo also; fi | tee and.txt # both get redirected
hello
also
$ cat - << EOF <(echo
> hello)
> boing
> EOF
bash: hello: command not found
boing
$ ( ( ( echo abc ) echo ) )
bash: syntax error near unexpected token `echo'
$ ( ( ( echo abc )
> echo also ) )
abc
also
$ ( ( echo one ) > file )
$ ( ( echo one ) > two ) > three
$ ( echo ) >> blah
$ if true; then echo; fi >> blah
$ cat - /proc/self/fd/3 << BOING 3<<MEEP
> one
> BOING
> aha
> MEEP
one
aha
$ cat - << BOING $(
echo hello)
abc
BOING
abc
blah
$ ( cat << EOF
> hello
> EOF
> )
hello
$ if cat << EOF
> hello
> EOF
> then
> echo fi
> fi
hello
fi
$ echo 2>&1
$ echo 2 >&1
$ echo 2 >& 1
$ if while true; do echo hello; done; then echo hi; fi
$ (echo &&)
$ (echo ;)
$ if true; then echo $X; fi {X}</dev/null
10
$ X=2; {X}<&-; boing # does not close stderr?
bash: boing: command not found
$ ls /proc/$$/fd
$ exec 10<& -
# >&; ;&>
# prompts before echoing
$ echo hello; if
> echo two; then echo three
> fi
hello
two
three
$ echo )hello
bash: syntax error near unexpected token `)'
$ echo {abc
{abc
$ echo {abc</dev/null
{abc
# innermost redirect wins
$ if cat <<< moo ; then cat <<< also; fi <<< potato
moo
also
$ (echo &&)
bash: syntax error near unexpected token `)'
$ funkiness() { env ; }
$ POTATO=blah funkiness | grep POTATO
POTATO=blah
$ echo $POTATO
$ chicken() { echo hello; chicken() { echo also ;}; chicken;}
$ chicken
hello
also
$ chicken
also
$ thingy() { echo hello; } | cat
$ thingy
bash: thingy: command not found
$ echo hello > >(sed 's/.*/abc&def/') > >(sed 's/.*/ghi&jkl/')
abcghihellojkldef
$ echo hello > one > two
$ yes | head -n 3 > >(wc -l >two) > >(wc -l >one)
landley at driftwood:~$ cat one
3
landley at driftwood:~$ cat two
0
$ </dev/null echo hello
hello
$ echo {+}</dev/null
{+}
$ echo {}</dev/null
{}
$ echo <
bash: syntax error near unexpected token `newline'
$ murgle() { echo > "$@" ;}
$ murgle one two three
bash: "$@": ambiguous redirect
$ murgle one
$ cat << " "
> abc
>
abc
$ cat << \"
> boing
> "
boing
$ echo hello &>> blah.txt
$ potato() { echo "$@"; }; IFS=1234 potato one two three
one two three
$ cat <<< {one,two,three}
{one,two,three}
$ cat <<< one two three
$ echo hello >&2-x && ls 2-x
2-x
$ while true; do sleep 1; read a; echo $a; [ -z "$a" ] && break; done << EOF &
> one
> two
> three
> EOF
[1] 30590
$ (set -o noclobber; echo > /dev/null)
$ (ln -s /dev/null blah; set -o noclobber; echo > blah)
$ (touch walrus; ln -s walrus penguin; set -o noclobber; echo > penguin)
$ funky() { A="$@" ;}; funky one two three; echo $A
one two three
$ export "()=42"
bash: export: `()=42': not a valid identifier
$ set hello="$@" > walrus
$ X=$(false) || echo true
true
$ for((i=1;i<5;i++));do echo $i;done
1
2
3
4
# when is (( a token vs ( (?
$ ((echo a) | sed s/a/b/)
b
$ ((1
> +2<1)); echo $?
1
$ X=ii;for $X in a b c; do echo $ii; done
bash: `$X': not a valid identifier
$ for i in 1 2 3 & do echo hello; done
bash: syntax error near unexpected token `&'
$ if true; then false; else true; elif true; then false; fi
bash: syntax error near unexpected token `elif'
$ while false; true; do echo hello; done | head -n 3
hello
hello
hello
$ せ=42
bash: せ=42: command not found
$ function abc=def () {echo hello;} ; "abc=def"
hello
$ ((echo hello) )
hello
$ abc() { for name; do echo $name; done;}; abc X Y Z
X
Y
Z
# In a for loop ;; breaks down to ; ;
$ for((i=0;;i++)); do echo $i; done | head -n 30
1
2
$ (()); echo $?
1
$ ((x=12)); echo $x
12
$ (echo 123) # redir prefix not used for non-redir end tokens
123
$ x=42; ! ((x<3)) && ((x<43)) && echo yes
yes
# redirects aren't in math
$ echo $((2<3))
1
$ echo $((2&3))
2
$ ((3<2)); echo $?
1
$ X=X; echo $((X+2))
bash: X: expression recursion level exceeded (error token is "X")
$ X=3 ((3<2)) || echo hello
bash: syntax error near unexpected token `('
$ echo $((`echo 1`))
1
$ X=3; (($X<3)) || echo no; (($X<4)) && echo yes
no
yes
$ cat <(echo "$(((1<2)) && echo "hello")")
hello
$ THINGY=whoami; echo "$("${THINGY}")"
landley
$ burble() #comment
> { echo hello;};burble
hello
$ for i=3
> do echo hello; done
bash: `i=3': not a valid identifier
$ ((1<2)) > blat
$ boing () { for name do echo $name; done }; boing one two three
one
two
three
$ cat <( "(" )
bash: (: command not found
$ break > potato 2>/dev/null || ls potato
potato
# too many error messages
$ break 1 37
bash: break: only meaningful in a `for', `while', or `until' loop
$ for i in 1; do break walrus; done
bash: break: walrus: numeric argument required
$ for i in 1; do break 37 walrus; done
bash: break: too many arguments
$ for i in 1; do break 0; done
bash: break: 0: loop count out of range
$ if true; then if false; then echo one; elif ! echo two; then echo three; else
echo four; fi; fi
two
four
$ cat boing |& sed s/boing/walrus/
cat: walrus: No such file or directory
# runs printing "hi" until segfault
bash -c "abc() { echo hi; def() { abc;echo lo;};def;}; abc"
# word splitting test
$ X="one two"; printf '%s\n' $X 2 3 | while read a; do echo $a; done
one
two
2
3
$ fff() { echo abc$*def;}; fff one two three | xargs -n 1 echo
abcone
two
threedef
$ ABC=abcdefg
$ echo ${ABC:+"}"}
}
$ for i in a b c d e; do break & done
[1] 25533
[2] 25534
[3] 25535
[4] 25536
[5] 25537
$ walrus=1; echo ${walrus+blah}
blah
$ unset walrus; echo ${walrus+blah}
$
$ echo echo hello | sh
hello
$ { { { echo hello;} ;} >blat ;} ; echo one; cat blat
one
hello
$ ABC=1
$ echo ${"AB"C}
bash: ${"AB"C}: bad substitution
$ echo ${"ABC"}
bash: ${"ABC"}: bad substitution
$ X='*'; echo $X
$ <&2-; ls boing # redirect undone at end of command
ls: cannot access 'boing': No such file or directory
$ ls boing <&2- # redirect applies to command
$ X=42 </dev/null ; echo $X # local assignment persists even with redirect
42
$ bash -c 'read i >/dev/null <<< boing; echo $i'
boing
# The expansions unquoted << _doesn't_ do.
$ cat << TEST
> ~landley
> *
> potato/{one,two,three}
> "hello"
> TEST
~landley
*
potato/{one,two,three}
"hello"
$ X="|"; echo hello $X and
hello | and
$ for i in a b c; do for j in d e f; do for k in g h i; do echo $i $j $k;
continue 3; done done done
a d g
b d g
c d g
More information about the Toybox
mailing list