Populate a record with a model?
Yii does have the equivalent populateRecord and populateRecords on CActiveRecord.

However, on both the populateModel(s) and populateRecord(s) methods, you should be very cautious of blindly mass-assigning untrusted inputs to models/records that participate in the Active Record pattern (like Craft/Yii does).

They can be susceptible to what's known as the Mass Assignment Vulnerability that many popular frameworks have been a victim of.

Yii does what it can to protect against this, but my personal preference is to explicitly assign each individual attributes on the model/record in the case of untrusted input to avoid the issue altogether.