Why is only one 'data' event emitted when stdout exceeds the buffer size?

Background: https://github.com/Almenon/AREPL-vscode/pull/332 (It's a lot, I suggest reading below first)I'm assuming node flushes stdout when the highWaterMark is reached. Is this correct? Assuming so, if the high water mark is surpassed the extra characters should come in a second flush, right?Node appears to be ignoring the high water mark and only flushing once, regardless of buffer size.Sample code reproducing my problem with expected / actual result: https://gist.github.com/Almenon/6286ca1baf0714b56dc133e03728eb12

Submitted May 10, 2020 at 04:53AM by Almenon