You can force print to fail by selecting a filehandle that you know is unwritable. Here's a quick-n-dirty little module that returns a tied filehandle that fails when written to: 
package NoPrint;
use Symbol;

sub new {
    my $sym = gensym;
    tie *$sym, $_[0];
    bless $sym, $_[0];
}
sub TIEHANDLE { bless {}, $_[0] }
sub PRINT { return undef }
sub PRINTF { return undef }
sub WRITE { return undef }

[download]
You can now use it like this: 
my $old_fh = select NoPrint->new;

## deep inside some test somewhere...
print "foo\n" or warn "print failed (1)";

select $old_fh;

## now printing is back to normal again:
print "foo\n" or warn "print failed (2)";

[download]
Update: An alternative that might even be is much cleaner is to localize *STDOUT: 
{
    local *STDOUT = NoPrint->new;
    print "foo\n" or warn "print failed (1)";
}

print "foo\n" or warn "print failed (2)";

[download]

blokhead

In reply to Re: Testing failures: How to override print to make it fail? by blokhead
in thread Testing failures: How to override print to make it fail? by eyepopslikeamosquito

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