BIND 10 #1649: Config show allows listing non-existing sub-item in list

[BIND 10 Development]

#1649: Config show allows listing non-existing sub-item in list
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                   Reporter:         |                 Owner:  UnAssigned
  vorner                             |                Status:  reviewing
                       Type:         |             Milestone:
  defect                             |  Sprint-20120221
                   Priority:  major  |            Resolution:
                  Component:  bind-  |             Sensitive:  0
  ctl                                |           Sub-Project:  Core
                   Keywords:         |  Estimated Difficulty:  3
            Defect Severity:  N/A    |           Total Hours:  0
Feature Depending on Ticket:         |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Changes (by jelte):

 * owner:  jelte => UnAssigned
 * status:  assigned => reviewing


Comment:

 Ready for review. As is usual in these parts of the code, I did a tiny bit
 more than just this fix;

 - first off I added a check for the above case, it should now report an
 error if a needed list index is missing. In the function that reports
 this, an additional argument can disable it (we need to have the ability
 not to specify indices when we are looking for a default value)
 - to make it a bit more readable, i added a few helper functions; these
 might also be useful for the inevitable refactor of the config data stuff
 (the raw structures for both specs and data were chosen deliberately in
 the beginning IIRC, but I want to get rid of them and use classes, which
 should make both the code and fixes like this one (and any other behaviour
 changes) a lot simpler)
 - changed a number of cases where the code of these helper functions was
 used directly

 and while i was at it, i ran into another easy to fix issue, which has
 been bugging me for quite some time, and now became absolutely annoying;

 - it strips off the '/' at the end of config commands; this should not
 have effect on the behaviour itself, but does produce much nicer output;
 no more things like
 {{{
 > config show Foo/
 Foo//bar1
 Foo//bar2
 }}}

-- 
Ticket URL: <http://bind10.isc.org/ticket/1649#comment:4>
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