Hey Joe!
Thanks for replying.
"Drop the field and re-run", yes, write checking code, yes.
I can even see the value in '"CalculateField_or_AddFieldIfItDoesNotExist"
But here is the timeline of events for my use of the geoprocessing tool that is called "CalculateField"
I have consistent fields through multiple features in multiple projects. One field is called "SRCSTATUS", a text field.
I have more or less hardcoded it as it is consistently added to multiple features and used regularly to pass information from office to field and back.
I upgraded to ArcGIS Pro. 2.5.0.
I have been writing code to go from CSV to GDB to Online.
To save time I created a dummy CSV that I forgot to put in "SRCSTATUS" as a field.
Because "CalculateField" in 2.5.0 is actually "CalculateField_or_AddFieldIfItDoesNotExist", I experienced no issues. In fact, the update to the tool FIXED my data. This happened twice in my code for the field "SRCSTATUS" and another field "MultiTag" (a short field).
However! I gave the code to my analyst to test, and it promptly failed at "CalculateField" on the test data. She lacks experience as to what to do and would have been stuck for hours had I not been online at the time. It took me a head scratch and a check of ArcGIS Pro versions (mine 2.5.0 hers 2.4.1) to realize something had changed.
I see a point where automated code will run and instead of errors stopping at mistakes (as it should), the mistakes keep going and going and going. I could perpetuate a misspelling or "mis-fielding" on ten's to hundreds to thousands of features.
Wait till I tell you what the update to "CaclulateField" did to a JOIN with a wrong field once I can understand what the heck went wrong there.