RFR: 8011350 : hgforesth.sh fails if sh is not bash

[Mike Duigou]

On Apr 3 2013, at 20:14 , David Holmes wrote:

> On 4/04/2013 9:30 AM, Mike Duigou wrote:
>> I've received some feedback from Tim Bell and David Katleman.
>> 
>> Here's an updated version of the patch.
>> 
>> http://cr.openjdk.java.net/~mduigou/JDK-8011350/2
>> 
>> It turns out the real shell incompatibility was more straightforward. The outright conversion to bash isn't necessary. Replacement of '==' with '=' and double to single quotes in the cut command are sufficient.
>> 
>> The whichhg changes are based on an observation by Tim Bell in another bug that some versions of Solaris "/usr/bin/which" don't generate an exit code and instead output the message "no foo in PATH". This change better handles no mercurial being present.
> 
> Seems to work. I confess I'm puzzled by the == issue as it doesn't seem to be a valid operator anywhere, yet worked with bash ??

Bash accepts both according to to http://www.gnu.org/software/bash/manual/bashref.html#Bash-Conditional-Expressions 

(The page also explicitly mentions = is more portable/compatible)

> 
> David
> 
>> Mike
>> 
>> On Apr 3 2013, at 08:56 , Mike Duigou wrote:
>> 
>>> An alternative has been suggested: convert the hgforest.sh script to a bash script. I have tested this alternative on unbuntu linux 11.04, solaris 10u9, MacOS 10.7 and cygwin 1.7.17. This seems like less risk and there doesn't seem to be a compelling reason to stick with classic sh.
>>> 
>>> I have prepared an alternate webrev here:
>>> 
>>> http://cr.openjdk.java.net/~mduigou/JDK-8011350/1
>>> 
>>> We could still consider the original webrev if using bash turns out to have unexpected issues.
>>> 
>>> Mike
>>> 
>>> On Apr 2 2013, at 20:03 , Mike Duigou wrote:
>>> 
>>>> Hello all;
>>>> 
>>>> Further testing on JDK-8011342 revealed that hgforest.sh can fail if the sh shell is not bash. The problem appears to be due to mixing of -o -a and ! in [] test expressions.
>>>> 
>>>> I have prepared a webrev here:
>>>> 
>>>> http://cr.openjdk.java.net/~mduigou/JDK-8011350/0/webrev/common/bin/hgforest.sh.udiff.html
>>>> 
>>>> This converts all of the potentially problematic [ expr -o expr ] [ expr -a expr ] and [ expr -{o|a} ! expr ] to use "test". My conversions are based on the advice of the autotools chapter on "Writing portable Bourne Shell" (http://sourceware.org/autobook/autobook/autobook_208.html#SEC208) for avoiding potential problems.
>>>> 
>>>> The other option is just to require bash which is already required by the new build process.
>>>> 
>>>> Mike
>>> 
>>