File.expand_path falls into infinite loop

[michaelklishin]

Some projects on travis-ci.org fail with fakefs going into an infinite loop, like so:

/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file.rb:122:in `expand_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:95:in `normalize_path'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/file_system.rb:100:in `current_dir'
/home/vagrant/.rvm/gems/rbx-head/gems/fakefs-0.3.2/lib/fakefs/dir.rb:107:in `pwd'
kernel/common/file.rb:445:in `expand_path'

[ghost]

I hit that issue, too. I guess FakeFS::File.expand_path shouldn't fall back to RealFile.expand_path.

[ghost]

I tried passing RealDir#pwd to File#expand_path, that fixed the infinite loop, at least. I'm now struggling with 4 more failures but haven't found out yet if they are related to expand_path or just simple bugs with Rubinius.

[ghost]

Patch submitted at #88

I'm pretty sure that the remaining errors and failures are not directly related to the infinite loop.

[ghost]

Do bundle exec rake on a more or less recent rbx-2.0.0pre for reproducing this.

[evanphx]

This happens because FakeFS stubs out soo much it confuses the heck out of Rubinius. FakeFS basically depends on the idea that ruby is NOT written in ruby.

I'm working on some fixes to Rubinius to mitigate the problem, but I fear that FakeFS in it's current incarnation will never be bug-free on Rubinius because of the constant internal confusion.