GRIB1 duplicate rule

[bblay]

No description provided.

[rhattersley]

What was the impact of the bug? Duplicated coords on the resulting cube? Could be worth a quick test just to help establish some unit test idioms.

@pelson - would you mind shepherding this one? @pp-mo and @bblay have been doing some low level GRIB testing which may help (or not ;-)).

[bblay]

It raised a ValueError('Duplicate coordinates are not permitted.').

It's a little frustrating that grib.py is largely made to support the current rules system.
From a brief chat with @pp-mo on his testing work I feel that if we could rewrite the load rules as atomic python functions (#182) we'd have an easier time with mocking and testing grib rules.

[bblay]

We should wait for the mock gribapi and grib message being developed in #184 before adding a test.

This should allow us to create a mock grib message with timeRangeIndicator == 4 and use the mock gribapi
to run the rules.

[pelson]

Clearing my assignment. I'd be happy to pick this up once its on the stack, but currently, there is no need to have an individual (and therefore be limited to a single person being able to pick this up) assigned.

@bblay - It looks like there is an action on you here.

Cheers,

[bblay]

Test pending #221

[bblay]

Rebased.

I don't think there is any test which is appropriate for this ticket.
The duplicate rule has been removed. It is not part of iris.
It seems wrong to check that we no longer have a certain rule in duplicate,
otherwise, shouldn't we do the same for all rules?

Recommend merging without a test in this rare occurrence.

[bblay]

rebased onto latest master for more thorough testing

[rhattersley]

If you're seeing a lot of weird commits in this PR it's because we removed a commit from master and some of the PRs have got themselves confused. A rebase will clear the problem.

NB. It doesn't need a rebase, you can create a new PR with exactly the same commit (i.e. pelson/iris@2bcf972) and it will be just fine. It might be possible to move the head of your PR somewhere else and then back again... but caveat emptor!