"doctest doctest" fails chdir error on old matlab

[cbm755]

>> doctest doctest        
Doctest v0.4.1: this is Free Software without warranty, see source.

Error using chdir
Cannot CD to doctest (Name is nonexistent or not a directory).
Error in doctest_collect (line 76)
  oldcwd = chdir(what);
Error in doctest (line 241)
  summary = doctest_collect(what{i}, directives, summary, recursive, fid); 

Works if I specify the path and .m:

>> doctest matlab/doctest/doctest.m
Doctest v0.4.1: this is Free Software without warranty, see source.

matlab/doctest/doctest.m ............................... PASS   10/10  

Summary:

   PASS   10/10  

1/1 targets passed, 0 without tests.

Fails if in the right dir (unless .m specified, then it works)

>> cd matlab/doctest 
>> doctest doctest                 
Doctest v0.4.1: this is Free Software without warranty, see source.

Error using chdir
Cannot CD to doctest (Name is nonexistent or not a directory).
Error in doctest_collect (line 76)
  oldcwd = chdir(what);
Error in doctest (line 241)
  summary = doctest_collect(what{i}, directives, summary, recursive, fid); 
>> 

[cbm755]

Cannot confirm this with master, using 2015b.

[cbm755]

I think I can confirm on 2014a. Workaround is doctest doctest.m.