[3.18] Metadata stability tests for modulemd metadata

[dralley]

closes #2242
#2242

(cherry picked from commit e9ddb74)

[dralley]

@ianballou @ggainey And now the API differences between 3.18 and 3.19 are apparent

TL;DR

• where libmodulemd defaulted to False for "static_context" when it's not present, we now currently store None
• indeed there was definitely an (unintentional) change where we now return rpms: [ ...list... ] for "artifacts" instead of just returning the list
• profiles and description fields were added, but we knew that already, that's intentional
• "dependencies" changed in a similar way to "artifacts", now it includes an outer level "requires" and "buildrequires" tag

@ianballou Just to confirm, you would like the behavior in bullet point 2 to remain the same as it is now in 3.19, even though it got changed unintentionally? How about 4, does that impact you at all?

[dralley]

E           AssertionError: []                                                   
E           assert [('change', 'static_context', (False, None)), ('change', 'artifacts', (['dwm-0:6.0-1.module_1997+c375c79c.src', 'dwm-0:6.0-1.module_1997+c375c7
9c.x86_64'], {'rpms': ['dwm-0:6.0-1.module_1997+c375c79c.x86_64', 'dwm-0:6.0-1.module_1997+c375c79c.src']})), ('add', ['dependencies', 0], [('requires', {'platfor
m': ['f29']}), ('buildrequires', {'platform': ['f29']})]), ('remove', ['dependencies', 0], [('platform', ['f29'])])] == []                                        E             Left contains 4 more items, first extra item: ('change', 'static_context', (False, None))
E             Full diff:                                                         
E               [
E             -  ,                                                               
E             +  ('change',                                                                                                                                       E             +   'static_context',                                              
E             +   (False,                                                        
E             +    None)),
E             +  ('change',                                                      
E             +   'artifacts',                                                   
E             +   (['dwm-0:6.0-1.module_1997+c375c79c.src',               
E             +     'dwm-0:6.0-1.module_1997+c375c79c.x86_64'],           
E             +    {'rpms': ['dwm-0:6.0-1.module_1997+c375c79c.x86_64',   
E             +              'dwm-0:6.0-1.module_1997+c375c79c.src']})),  
E             +  ('add',                                                         
E             +   ['dependencies',                                               
E             +    0],                                                           
E             +   [('requires',                                                                                                                                   E             +     {'platform': ['f29']}),                                   
E             +    ('buildrequires',                                             
E             +     {'platform': ['f29']})]),
E             +  ('remove',                                                      
E             +   ['dependencies',                                                                                                                                
E             +    0],                                                                                                                                            
E             +   [('platform',                                                                                                                                   
E             +     ['f29'])]),                                                  
E               ]

[ianballou]

@ianballou Just to confirm, you would like the behavior in bullet point 2 to remain the same as it is now in 3.19, even though it got changed unintentionally? How about 4, does that impact you at all?

@dralley yeah now that Katello has the fix let's keep things as-is. I don't remember fixing the dependencies part, but our dependencies don't appear to be broken for packages, so we should be all set.

[dralley]

Ok. It definitely shouldn't affect the metadata at all, just if you have any ui elements that query that data from the API