about_files.pl

#!/usr/bin/perl
=pod
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    reproduce the above copyright notice, this list of conditions and the following
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=cut

package Perl::Koans::Files;
use warnings;

use lib './lib';
use Perl::Koans;

################
# your code goes below this line

sub about_file_tests {
    # about_file_tests() -- http://perldoc.perl.org/perlfunc.html#Alphabetical-Listing-of-Perl-Functions has the full list (just look at those prefixed with -)
    
    my %files = (
        does_not_exist => 'this file does not exist',
        readable       => 'road_to_illumination.pl',
        not_executable => 'about_files.pl',
        owned          => 'about_time.pl', # it doesn't matter, any file will work
        this_is_a_dir  => 'lib',
        file_exists    => 'about_math.pl',
        empty          => '',
        not_a_link     => 'about_io.pl',
        
    );
    
    # TODO is it ok to not cover the 'real uid/gid' cases? personally, i've never used anything except effective
    is (-e $files{file_exists},    __, "-e file exists");
    is (-f $files{does_not_exist}, __, "-f file is a file");
    is (-d $files{this_is_a_dir},  __, "-d file is a directory");
    is (-r $files{readable},       __, "-r file is readable by effective UID/GID"); 
    is (-x $files{not_executable}, __, "-x file is executable by effective UID/GID");
    is (-o $files{owned},          __, "-o file is owned by effective UID/GID");
    is (-z $files{empty},          __, "-z file has size of zero");
    is (-l $files{not_a_link},     __, "-l file is a symbolic link");
    
    return (Perl::Koans::get_return_code());
}

sub about_stat {
    # stat -- http://perldoc.perl.org/functions/stat.html
    
    # create a file so we can do something
    my $filename = 'test.txt';
    open (my $fh, '>', $filename) or die sprintf('DIE:: unable to open [%s] for writing: %s', $filename, $!);
    print $fh "this is just a test\n";
    close ($fh);
    
    my @stat = stat($filename);
    is ($stat[4],  __, "the 4th index of stat is UID of file owner");
    is ($stat[5],  __, "the 5th index of stat is GID of file owner");
    is (__,        21, "the 7th index of stat is file size");
    is ($stat[8],  __, "the 8th index of stat is last access time since epoch");
    is ($stat[9],  __, "the 9th index of stat is last modify time since epoch");
    is ($stat[10], __, "the 10th index of stat is inode change time since epoch");
    
    # whenever an operation can fail, you should provide some 'error handling', see about_exceptions.pl for more
    unlink($filename) if -f $filename; 
    
    return (Perl::Koans::get_return_code());
}


# your code goes above this line
################

unless (caller(0)) {
    run(@ARGV) or print_illumination();
    exit();
}

sub run {
    # run() -- runs all functions in this module
    my $results = 0;
    
    $results += about_file_tests();
    $results += about_stat();
    
    return ($results) ? bail($results) : $results;
}


1;