From: Joel VanderWerf <vjoel@...>
Date: 2005-02-22T15:18:55+09:00
Subject: Re: Require  when Executed file is required by another file.

Zev Blut wrote:
> On Tue, 22 Feb 2005 04:42:03 +0900, Joel VanderWerf  
> <vjoel@PATH.Berkeley.EDU> wrote:
> 
>> Zev Blut wrote:
>>
>>> A coworker of mine just commented why not just use File.expand_path for
>>> the required file?  Is there any reason not to do this?
>>
>>
>> Symlinks...
>>
>> $ cd /tmp
>> $ touch foo
>> $ ln -s foo bar
>> $ ruby -e 'p File.expand_path("foo")'
>> "/tmp/foo"
>> $ ruby -e 'p File.expand_path("bar")'
>> "/tmp/bar"
> 
> 
> Yes that is true, but I noticed if you actually go to directory with
> a symlink, it will expand to the true path.  Like so:
> 
> $ cd /tmp/
> $ mkdir foo
> $ ln -s foo bar
> $ touch foo/baz.rb
> $ ruby -e 'Dir.chdir("foo") ;p File.expand_path("baz.rb")'
> "/tmp/foo/baz.rb"
> $ ruby -e 'Dir.chdir("bar") ;p File.expand_path("baz.rb")'
> "/tmp/foo/baz.rb"
> 
> Is this portable or are there other problems with doing it this way?

Hm, I didn't expect that. And also:

$ ruby -e 'Dir.chdir("bar") ;p Dir.pwd'
"/tmp/foo"

In the shell (using linux, zsh) it works differently:

$ cd bar
$ pwd
/tmp/bar

Another data point:

$ ruby -e 'Dir.chdir("bar"); puts `pwd`'
/tmp/foo

I guess ruby follows symlinks when doing Dir.chdir?

Anyway, it doesn't solve the problem of a symlinked .rb file, if that's 
a problem.