[BUG] test ! "-o" ([ ! -o ]) exit status should be 1

[koichi nakashima <koichi@xxxxxxxxx>]

In the following code, I expected the exit status to be 1.
However, in zsh 5.0.3 and later, it was actually 0.

$ zsh -c '[ ! -o ]; echo "$ZSH_VERSION: $?"'
4.3.17: 1
$ zsh -c '[ ! -o ]; echo "$ZSH_VERSION: $?"'
5.0.0: 1
$ zsh -c '[ ! -o ]; echo "$ZSH_VERSION: $?"'
5.0.2: 1
$ zsh -c '[ ! -o ]; echo "$ZSH_VERSION: $?"' # <===
5.0.3: 0
$ zsh -c '[ ! -o ]; echo "$ZSH_VERSION: $?"'
5.8: 0

I checked the release notes, and it does not appear to be
an intentional change.


In other latest shells, it is as expected.
$ dash -c '[ ! -o ]; echo $?'
1
$ bash -c '[ ! -o ]; echo $?'
1
$ ksh -c '[ ! -o ]; echo $?'
1
$ yash -c '[ ! -o ]; echo $?'
1