Re: [ ! ! hey ] -> [: too many arguments

[Emanuele Torre]

On 22/06/23 11:08 PM, Steffen Nurpmeso wrote:
> or even
>  bash -c 'if [ ! ! hey = hey ]; then echo du; fi'
>  bash -c 'if [ ! false = 1 ]; then echo du; fi'

`! ! hey = hey' is the same as `! ( ! ( hey = hey ) )', so
"not not true => true".

It probably works correctly because `! ! hey = hey' are five terms.

The bug only occurs for 3 or 4 terms tests:

    bash-5.1$ test ! ! hey         ; printf %s\\n "$?"
    bash: test: too many arguments
    2

    bash-5.1$ test ! ! ! hey       ; printf %s\\n "$?"
    bash: test: too many arguments
    2

    bash-5.1$ test ! ! ! ! hey     ; printf %s\\n "$?"
    0

    bash-5.1$ test ! ! ! ! ! hey   ; printf %s\\n "$?"
    1

test(1) needs to treat the 0 to 4 arguments expressions specially
according to POSIX so the bug is probably only in the code that
implements those special cases.

 -emanuele6