D3 .extent() rejecting array of Dates in typescript

I’m struggling to utilize d3’s .extent() function in typescript.

I’ve got some code here that creates Date objects out of dates

 const dates:(Date | null)[] = data.map(row => d3.timeParse("%Y-%m-%d")(row.Date))

When I console log the dates variable, it looks something like this

[Sat Jun 24 2023 00:00:00 GMT-0700 (Pacific Daylight Time), Sat Jun 24 2023 00:00:00 GMT-0700 (Pacific Daylight Time), Fri Jun 23 2023 00:00:00 GMT-0700 (Pacific Daylight Time), Fri Jun 23 2023 00:00:00 GMT-0700 (Pacific Daylight Time), Fri Jun 23 2023 00:00:00 GMT-0700 (Pacific Daylight Time), ...]

Therefore, I know my dates variable is full of Date objects, like expected…

However, when I try and use the d3.extent() function to find the highest and lowest dates

const xScale = d3
      .scaleTime()
      .domain(d3.extent(dates))

Argument of type '[undefined, undefined] | [string, string]' is not assignable to parameter of type 'Iterable<Date | NumberValue>'.

I’m confused as to why this might be, though, as my dates variable is in fact exclusively dates, and not, as is expressed in the error, ‘[undefined, undefined] | [string, string]’.

What is wrong about what I am passing in? How should I be passing in dates to the extent() function in typescript?