I thought this would work 
#!/usr/bin/perl --
BEGIN {
    package OOO;
    sub new      { my( $pkg, $path ) = @_; bless \$path, $pkg; }
    sub filetest { warn "its fake @_\n"; 'fake' }
    use overload '-X' => \&filetest;
    $INC{'OOO.pm'} = __FILE__;
}
use strict; use warnings;
use OOO;
-f OOO->new('.');
__END__
Operation """": no method found, argument in overloaded package OOO at
+ - line 6.

[download]

I don't understand, what did I miss?
http://perl5.git.perl.org/perl.git/blob?f=gv.c#l3022
http://perl5.git.perl.org/perl.git/blob?f=t/op/filetest_stack_ok.t#l17
http://perl5.git.perl.org/perl.git/blob?f=t/op/magic.t#l617
http://perl5.git.perl.org/perl.git/blob?f=lib/overload.t#l1840

In reply to mocking overloading filetest operator callback -f -d -e -X by Anonymous Monk

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