“wrangler pages functions build” yields output with different filenames

I'm building my Pages' functions with the following command

wrangler pages functions build ./functions --sourcemap --compatibility-flags=nodejs_compat --outdir=./dist-functions/

wrangler pages functions build ./functions --sourcemap --compatibility-flags=nodejs_compat --outdir=./dist-functions/

Its output is either

index.js

index.js

index.js.map

index.js.map

_worker.js

_worker.js

worker.js.map

worker.js.map

Why is that?
How can I ensure it's output is the same all the time?
How can I make it always be

_worker.js

_worker.js

worker.js.map

worker.js.map

?

Wrangler version:

3.28.2

3.28.2

I tried to use

--outfile

--outfile

option instead of

--outdir

--outdir

, but in this case the sourcemap stops generating.