Fix da.broadcast_to call when the fx cube has different shape than target data cube

[valeriupredoi]

Description

We spotted a bug in the landsea masking related to the broadcasting of the fx data array onto the cube to be masked data array.

Closes #1349

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[zklaus]

I'm willing to accept this as a hot-fix as-is. But would you consider adding the test? If not, let's open an issue about that.

[codecov]

Codecov Report

Merging #1350 (40b3bf3) into main (d587d0c) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1350      +/-   ##
==========================================
+ Coverage   88.24%   88.26%   +0.02%     
==========================================
  Files         194      194              
  Lines        9831     9831              
==========================================
+ Hits         8675     8677       +2     
+ Misses       1156     1154       -2     

Impacted Files	Coverage Δ
esmvalcore/preprocessor/_mask.py	85.21% <100.00%> (+0.86%)	⬆️

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[valeriupredoi]

@zklaus sorry, was working on the test, now included too, it's a cold-fix now 😁

[sloosvel]

Sorry about the slip-up. I think I spotted more buggy things in #1269 , can they be fixed here as well?

[zklaus]

If it's small, yes, if it's not so small, perhaps we merge this first and take it separately. What did you discover?

[valeriupredoi]

be my guest @sloosvel - cheers! Make sure you pull the latest, I just added a bunch o'changes to the integration test mask 👍 Let's agree we want this in 2.4 so let's hustle up on it, and get it ready before the day of release 🍺

[sloosvel]

def _preserve_fx_vars(cube, result):
    vertical_dim = set(cube.coord_dims(cube.coord(axis='z', dim_coords=True)))
    if cube.cell_measures():
        for measure in cube.cell_measures():
            measure_dims = set(cube.cell_measure_dims(measure))
            if vertical_dim.intersection(measure_dims):
                logger.warning(
                    'Discarding use of z-axis dependent cell measure %s '
                    'in variable %s, as z-axis has been interpolated',
                    measure.var_name, result.var_name)
            else:
                add_cell_measure(result, measure, measure.measure)
    if cube.ancillary_variables():
        for ancillary_var in cube.ancillary_variables():
            ancillary_dims = cube.ancillary_variable_dims(ancillary_var)   --> this should be set(cube.ancillary_variable_dims(ancillary_var) )
            if vertical_dim.intersection(ancillary_dims):
                logger.warning(
                    'Discarding use of z-axis dependent ancillary variable %s '
                    'in variable %s, as z-axis has been interpolated',
                    ancillary_var.var_name, result.var_name)
            else:
                add_ancillary_variable(result, ancillary_var)

And I only added tests for climate_statistics, they should also be added for decadal_statistics, annual_statistics, etc.

[zklaus]

Since this is already done and the checks are passed, I'd rather merge it as is. The changes you mention in total seem a bit more substantial. Please open a new PR.

[zklaus]

@valeriupredoi, could you please take care of the checklist while I do the review?

[zklaus]

Minimal change requested, also ok as-is.

[valeriupredoi]

OK @zklaus cheers for taking a look/reviewing - I agree we can merge and then Saskia can do the other changes in a subsequent PR (bit too much for this PR methinks too). Cheers both for looking into it! 🍺