Subject: bug#10390: closed (Re: bug#10390: Bug with Test Command)

From: [email-masked] (GNU bug Tracking System)
Date: Wed, 28 Dec 2011 13:31:02 +0000

Your bug report

#10390: Bug with Test Command

which was filed against the coreutils package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
10390: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=10390
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#10390: Bug with Test Command
From: Eric Blake <[email-masked]>
To: "Mathi.C" <[email-masked]>
Cc: [email-masked]
Date: Wed, 28 Dec 2011 06:28:06 -0700
List-Id: <debbugs-submit.debbugs.gnu.org>

tag 10390 notabug
thanks

On 12/27/2011 11:12 PM, Mathi.C wrote:
> Hi,
> 
> I have come across a scenario where test command resulted wrong result than
> expected.
> 
> Please follow the below steps to simulate the scenario.
> 1. Define a variable to blank/null
>      export a=
> 2. Test the parameter with test command on file exists
>      test -f $a

There's your problem.  You failed to properly quote things.  Per shell
expansion rules, unquoted $a is elided, rather than an empty argument,
which means you passed test exactly one argument ("-f"), and since that
one argument is not empty, it is always true.

If you want to cope with an explicit empty string, you must use quoting:

test -f "$a"

> 3. Echo the result of the last executed command
>     echo $?

As this behavior matches POSIX requirements on test, there is nothing to
fix here.  Also, be aware that you were probably testing your shell's
built-in test, rather than coreutils' test (running the latter usually
requires that you do things like 'env test' or '/usr/bin/test' to bypass
shell built-ins).

-- 
Eric Blake   [email-masked]    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

Subject: Bug with Test Command
From: "Mathi.C" <[email-masked]>
To: [email-masked]
Date: Wed, 28 Dec 2011 00:12:49 -0600
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi,

I have come across a scenario where test command resulted wrong result than
expected.

Please follow the below steps to simulate the scenario.
1. Define a variable to blank/null
     export a=
2. Test the parameter with test command on file exists
     test -f $a
3. Echo the result of the last executed command
    echo $?

Result we get is "0" -success, whereas the test command (step 2) should
error with parameter expected after " test -f".

-- 
Regards,
Mathi.C