Add option for readdir to prepend the relative or absolute path

[tamasgal]

This is a simple implementation of the feature request created by @yakir12 in #29309 after discussing it on https://discourse.julialang.org/t/readdir-return-full-path/15274?u=yakir12

[tamasgal]

Unfortunately I am not able to run the test suite (I get segmentation faults) so there are no unit tests yet until I figure out what's going on.

[StefanKarpinski]

I'm not really into this change. The readdir function does one very simple thing: it reads the contents of a directory, which is a vector of the names in that directory. Yes, you can do all sorts of complicated stuff with that, but that's up to you.

[yakir12]

So you feel that adding that option over-complicates readdir?

[tamasgal]

Well, I have never used readdir() to just retrieve a list of filenames in a given directory. I always use it to directly work with the files (e.g. in mass processing), so I need the full path (relative or absolute, doesn't matter). I think that most of the people who liked that idea do the same.

I know that one can use Glob, but that would be an additional dependency.

[StefanKarpinski]

So you feel that adding that option over-complicates readdir?

Yes. Note that the C function by the same name and the Python os.listdir function have the same behavior.

[tamasgal]

OK, let's close this then!

[StefanKarpinski]

Something about closing this kept nagging at me—after all, it is often more convenient to get joined paths or absolute paths. One of the things that bothers me about this proposed API is that it's non-orthogonal: if you set abspath=true then the join option no longer matters. So I've opened #33113 as an alternative that only introduces join and doesn't add the abspath option. Instead you can get absolute paths by passing an absolute directory name and asking for joined names.

[yakir12]

Win win!

[tamasgal]

Nice! I like #33113, I am totally fine with the join-functionality only ☺️

[rfourquet]

Something about closing this kept nagging at me

Same for me and I wanted to look closer at this but you reacted faster, nice!