Fix date idate subtraction

[ben-schwen]

Closes #7825
Follows #7827

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.01%. Comparing base (46d0934) to head (b6bca2a).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #7828   +/-   ##
=======================================
  Coverage   99.01%   99.01%           
=======================================
  Files          88       88           
  Lines       17234    17239    +5     
=======================================
+ Hits        17065    17070    +5     
  Misses        169      169           

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[MichaelChirico]

Looks good at a glance. Let's merge the atime test first so we can see the performance change directly in the PR.

[github-actions]

• HEAD=fix_date_idate_sub much faster for Date-IDate subtraction regression in #7213
  

Generated via commit b6bca2a

Download link for the artifact containing the test results: ↓ atime-results.zip

Task	Duration
R setup and installing dependencies	3 minutes and 3 seconds
Installing different package versions	50 seconds
Running and plotting the test cases	8 minutes and 59 seconds

[MichaelChirico]

Hmm I'm still not seeing the right thing in the {atime} result, I reckon? I see 'Before' below the other timings!

[ben-schwen]

Hmm I'm still not seeing the right thing in the {atime} result, I reckon? I see 'Before' below the other timings!

Good catch. Apparently and unfortunately we need to reregister more. Now the test LGTM

[MichaelChirico]

Now we're cooking (funnily enough it does look to be catching up around N=1e7 👀 )