Add temporary directory creation on Dir class

[marceloboeira]

Usage:

Without prefix:

puts Dir.mktmpdir
# => /tmp/c.a39bF4

With prefix:

puts Dir.mktmpdir("foo")
# => /tmp/foo.a39bF4

The solution uses the LibC.mkdtemp bind.
The mkdtemp function creates a directory with a unique name. If it
succeeds, it overwrites template with the name of the directory, and
returns template. As with mktemp and mkstemp, template should be a
string ending with ‘XXXXXX’.

Reference:

• http://www.gnu.org/software/libc/manual/html_node/Temporary-Files.html

[marceloboeira]

@jhass for some reason the tests are failing only on linux builds, could you take a look to check what I'm doing wrong?

[jhass]

If TMPDIR wasn't set, this keeps it set at "/my/tmp".

[marceloboeira]

Thanks, I'll fix that!

[marceloboeira]

I was trying to create a better interface to work with temporary directories, something like:

Dir.mktmpdir do |dir|
....
end

On which the tmp dir only exists within the block lifecycle. However for that I'll need a Dir.rm_rf function, which I'll implement later on another pull request.

[asterite]

There's FileUtils.rm_r

[marceloboeira]

@asterite thanks, I didn't remembered to check FileUtils.

[marceloboeira]

@jhass @asterite done, can you check it?

[asterite]

Thanks! Before merging this, I would try to think of a different name, mktmpdir is pretty cryptic and reminiscent of libc.

[marceloboeira]

@asterite I was trying to keep Ruby's syntax, I would happily take your name suggestions.

[luislavena]

I'm not sure if is good that we add FileUtils as dependency for Dir, which is part of prelude and means that FileUtils will be parsed, analyzed and potentially included as part of every compiled program.

Perhaps this helper method can be treated in similar way as Tempfile? (ala: a separate class).

Just a thought.

[marceloboeira]

@luislavena you are absolutely correct, I was actually wondering why the paths were being concatenated that way (a + b...) but considering your comment, which haven't crossed my mind until now, makes sense.

However I think we should find a more elegant way of doing this.

Either way, for now I will fix this.

[asterite]

Ideally we should have a way to do rm_r in Dir, with a better name, and have FileUilts.rm_r use that method, like in my comment here.

[marceloboeira]

@asterite can I refactor this and move rm_r to Dir ?

[asterite]

@marceloboeira Ideally I'd like this method to be in Dir and in FileUtils. FileUtils would have methods names similar to bash functions, but Dir would have less cryptic names.

Problem is, I don't know what a good name for Dir is in this case.

[ysbaddaden]

What about:

module Dir
  def self.delete(path, *, recursive= false)
  end
end

[marceloboeira]

Could you accept this pull request and we rename the methods later? I really would like this feature for some projects and I would not like to "monkey patch". Also I think this is something important for several projects, not only mine.

[asterite]

@marceloboeira There's nothing wrong with "monkey patching" until this gets merged with time

[grosser]

so the only thing missing here is rename rm_r to delete ... or what is ?

... would love to use this feature :)

[marceloboeira]

@grosser not sure anymore. I need this feature, I believe I will create a temp shard to use it while I wait for it to be merged.

[sdogruyol]

This is pretty useful, especially for writing tests 👍

[bramswenson]

I've submitted a PR that is simply a rebase of this one to master. #4096

[marceloboeira]

@bramswenson thx!