74 lines
1.5 KiB
Perl
74 lines
1.5 KiB
Perl
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#!./perl
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use strict;
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use warnings;
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use Test::More tests => 9;
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use List::Util qw(sample);
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{
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my @items = sample 3, 1 .. 10;
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is( scalar @items, 3, 'returns correct count when plentiful' );
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@items = sample 10, 1 .. 10;
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is( scalar @items, 10, 'returns correct count when exact' );
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@items = sample 20, 1 .. 10;
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is( scalar @items, 10, 'returns correct count when short' );
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}
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{
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my @items = sample 5, 1 .. 5;
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is_deeply( [ sort { $a <=> $b } @items ], [ 1 .. 5 ],
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'returns a permutation of the input list when exact' );
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}
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{
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# These two seeds happen to give different results for me, but there is the
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# smallest 1-in-2**48 chance that they happen to agree on some platform. If
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# so then pick a different seed value.
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srand 1234;
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my $x = join "", sample 3, 'a'..'z';
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srand 5678;
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my $y = join "", sample 3, 'a'..'z';
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isnt( $x, $y, 'returns different result on different random seed' );
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srand;
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}
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{
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my @nums = ( 1..5 );
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sample 5, @nums;
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is_deeply( \@nums, [ 1..5 ],
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'sample does not mutate passed array'
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);
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}
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{
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my $destroyed_count;
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sub Guardian::DESTROY { $destroyed_count++ }
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my @ret = sample 3, map { bless [], "Guardian" } 1 .. 10;
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is( $destroyed_count, 7, 'the 7 unselected items were destroyed' );
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@ret = ();
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is( $destroyed_count, 10, 'all the items were destroyed' );
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}
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{
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local $List::Util::RAND = sub { 4/10 };
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is(
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join( "", sample 5, 'A'..'Z' ),
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join( "", sample 5, 'A'..'Z' ),
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'rigged rand() yields predictable output'
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);
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}
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