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Regression: ParquetWriter.CreateRowGroup calls Stream.Position for no reason

See original GitHub issue

Version: Parquet.Net v… 4.10

Runtime Version: .Net 6

OS: Windows

Expected behavior

Writing to a writeable stream should not throw exceptions. This was true in v3.x.

Actual behavior

Writing to a write-only stream that does not support Position throws an exception when calling CreateRowGroup, because it instantiates a new ParquetRowGroupWriter(), and the constructor asks for the stream’s Position property.

The only thing it does with this value is to store it to a field that is never used. So not only is this throwing exceptions, it is doing so completely pointlessly.

Code snippet reproducing the behavior

var pipe = new System.IO.Pipelines.Pipe();
var input = pipe.Writer.AsStream(); //write-only stream
var pWriter = new ParquetWriter(GetSchema(), input); //GetSchema should simply return any valid schema
var group = writer.CreateRowGroup(); //explodes here