Fix snapshot tests

[glatterf42]

The snapshot tests have been failing for a while now. Initially, if I remember correctly, there was some issue with retrieving the snapshots consistently, but that seems to be resolved. Now, one test fails because it's looking for the PRICE_EMISSION_NEW variable: the legacy reporting we migrated is built on top of https://github.com/iiasa/message_ix/tree/issue/723, which introduced that variable name to fix PRICE_EMISSION.

While we have unfortunately still not finished the corresponding PR, the branch has progressed to a point where PRICE_EMISSION was actually updated instead of a new helper variable introduced. This PR thus adjusts the variable name the migrated legacy reporting expects.

How to review

• Read the diff and note that the CI checks all pass.
• Note that the TEMPORARY commit should be dropped before merging

PR checklist

• Continuous integration checks all ✅
• Update tests
• [ ] Add, expand, or update documentation. Just CI.
• [ ] Update doc/whatsnew. Just CI.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 66.5%. Comparing base (ae7b63f) to head (d5665a6).

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #231     +/-   ##
=======================================
+ Coverage   65.5%   66.5%   +0.9%     
=======================================
  Files        203     203             
  Lines      15819   15819             
=======================================
+ Hits       10375   10523    +148     
+ Misses      5444    5296    -148     

see 7 files with indirect coverage changes

[khaeru]

A passing thought: in theory, a similar/parallel change should have been made to the legacy reporting somewhere, perhaps on the (private) message_data branch SSP_dev (or whatever the name is) that is directly using the branch from iiasa/message_ix#726. Otherwise it would also break without PRICE_EMISSION_NEW.

Is there someone we can ask to point us there so we can confirm this is aligned?

[glatterf42]

Good point, thanks :)
Here's the corresponding commit from two weeks ago: https://github.com/iiasa/message_data/commit/221b6de7309ec390c7d9981e5c7b554430205d5f

[khaeru]

Great, thanks for confirming. LGTM.