rows property
Rows is how many rows the source held for that window at materialisation time. Holds is the same question asked now, and the difference between them is the whole of the reproducibility claim.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
int? rows;