d7c92411dc introduced a warning for
non-existent files from components not mentioned in Components to hint
users at a mispelling or the disappearance of a component.
The debian-installer subcomponent isn't actively advertised in the
Release file through, so if apt ends up in acquiring a file which
doesn't exist for this component (like Translation files) apt would
produce a warning:
W: Skipping acquire of configured file
'main/debian-installer/i18n/Translation-en' as repository
'http://deb.debian.org/debian buster InRelease' doesn't have the
component 'main/debian-installer' (component misspelt in sources.list?)
We prevent this in the future by checking if any file exists from this
component which results in the warning to be produced still for the
intended cases and silence it on the d-i case.
This could potentially cause the warning not to be produced in cases it
should be if some marginal file remains, but as this message is just a
hint and the setup a bit pathological lets ignore it for now.
There is also the possibility of having no file present as they would
all be 0-length files and being a "hidden" component, but that would be
easy to workaround from the repository side and isn't really actively used
at the moment in the wild.