Better error message for divergence with no dt_min

[RemDelaporteMathurin]

Proposed changes

Fixes #888

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Code refactoring
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• New tests

Checklist

• Black formatted
• Unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.56%. Comparing base (abe3942) to head (ebb4d70).
Report is 12 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #889   +/-   ##
=======================================
  Coverage   99.56%   99.56%           
=======================================
  Files          61       61           
  Lines        2750     2752    +2     
=======================================
+ Hits         2738     2740    +2     
  Misses         12       12           

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[KulaginVladimir]

The fix looks ok to me. Maybe, combine if-clauses? dt_min has to exists for the second check.

[RemDelaporteMathurin]

If dt_min is None, then the second check won't even be run.
If you're talking about the if float(self.value) < dt_min: line

[KulaginVladimir]

yes, I understand.
I meant smth like that so the checks would be placed together:

if dt_min is None:
    ...
elif float(self.value) < dt_min:
    ...

[RemDelaporteMathurin]

No need since the first check will raise an error if True. They can be considered as completely independent