t/52_DGrow.t

   1 #!/usr/bin/perl
   2
   3 use strict;
   4 use warnings;
   5
   6 use Test::More tests => 15;
   7 use Test::NoWarnings;
   8
   9 use Data::Peek qw( DGrow DDump );
  10
  11 my $x = "";
  12 is (length ($x), 0,             "Initial length = 0");
  13 my %dd = DDump $x;
  14 ok ($dd{LEN} <= 16);
  15 my $len = 10240;
  16 ok (my $l = DGrow ($x, $len),   "Set to $len");
  17 is (length ($x), 0,             "Variable content");
  18 ok ($l >= $len,                 "returned LEN >= $len");
  19 my $limit = 4 * $len;
  20 ok ($l <= $limit,               "returned LEN <= $limit");
  21    %dd = DDump $x;
  22 ok ($dd{LEN} >= $len,           "LEN in variable >= $len");
  23 ok ($dd{LEN} <= $limit,         "LEN in variable <= limit");
  24 ok ($l = DGrow (\$x, $limit),   "Set to $limit");
  25 ok ($l >= $limit,               "LEN in variable >= $limit");
  26 ($len, $limit) = ($limit, 4 * $limit);
  27 ok ($l <= $limit,               "LEN in variable <= $limit");
  28    %dd = DDump $x;
  29 ok ($dd{LEN} >= $len,           "LEN in variable >= $len");
  30 ok ($dd{LEN} <= $limit,         "LEN in variable <= $limit");
  31 is (DGrow ($x, 20), $l,         "Don't shrink");
  32
  33 1;