t/02_MRO.t

   1 #!/usr/bin/perl
   2
   3 use strict;
   4 use warnings;
   5
   6 use Test::More tests => 15;
   7
   8 BEGIN {
   9     use_ok('Class::C3');
  10     # uncomment this line, and re-run the
  11     # test to see the normal p5 dispatch order
  12     #$Class::C3::TURN_OFF_C3 = 1;
  13 }
  14
  15 =pod
  16
  17 This example is take from: http://www.python.org/2.3/mro.html
  18
  19 "My first example"
  20 class O: pass
  21 class F(O): pass
  22 class E(O): pass
  23 class D(O): pass
  24 class C(D,F): pass
  25 class B(D,E): pass
  26 class A(B,C): pass
  27
  28
  29                           6
  30                          ---
  31 Level 3                 | O |                  (more general)
  32                       /  ---  \
  33                      /    |    \                      |
  34                     /     |     \                     |
  35                    /      |      \                    |
  36                   ---    ---    ---                   |
  37 Level 2        3 | D | 4| E |  | F | 5                |
  38                   ---    ---    ---                   |
  39                    \  \ _ /       |                   |
  40                     \    / \ _    |                   |
  41                      \  /      \  |                   |
  42                       ---      ---                    |
  43 Level 1            1 | B |    | C | 2                 |
  44                       ---      ---                    |
  45                         \      /                      |
  46                          \    /                      \ /
  47                            ---
  48 Level 0                 0 | A |                (more specialized)
  49                            ---
  50
  51 =cut
  52
  53 {
  54     package Test::O;
  55     use Class::C3;
  56
  57     package Test::F;
  58     use Class::C3;
  59     use base 'Test::O';
  60
  61     package Test::E;
  62     use base 'Test::O';
  63     use Class::C3;
  64
  65     sub C_or_E { 'Test::E' }
  66
  67     package Test::D;
  68     use Class::C3;
  69     use base 'Test::O';
  70
  71     sub C_or_D { 'Test::D' }
  72
  73     package Test::C;
  74     use base ('Test::D', 'Test::F');
  75     use Class::C3;
  76
  77     sub C_or_D { 'Test::C' }
  78     sub C_or_E { 'Test::C' }
  79
  80     package Test::B;
  81     use Class::C3;
  82     use base ('Test::D', 'Test::E');
  83
  84     package Test::A;
  85     use base ('Test::B', 'Test::C');
  86     use Class::C3;
  87 }
  88
  89 Class::C3::initialize();
  90
  91 is_deeply(
  92     [ Class::C3::calculateMRO('Test::F') ],
  93     [ qw(Test::F Test::O) ],
  94     '... got the right MRO for Test::F');
  95
  96 is_deeply(
  97     [ Class::C3::calculateMRO('Test::E') ],
  98     [ qw(Test::E Test::O) ],
  99     '... got the right MRO for Test::E');
 100
 101 is_deeply(
 102     [ Class::C3::calculateMRO('Test::D') ],
 103     [ qw(Test::D Test::O) ],
 104     '... got the right MRO for Test::D');
 105
 106 is_deeply(
 107     [ Class::C3::calculateMRO('Test::C') ],
 108     [ qw(Test::C Test::D Test::F Test::O) ],
 109     '... got the right MRO for Test::C');
 110
 111 is_deeply(
 112     [ Class::C3::calculateMRO('Test::B') ],
 113     [ qw(Test::B Test::D Test::E Test::O) ],
 114     '... got the right MRO for Test::B');
 115
 116 is_deeply(
 117     [ Class::C3::calculateMRO('Test::A') ],
 118     [ qw(Test::A Test::B Test::C Test::D Test::E Test::F Test::O) ],
 119     '... got the right MRO for Test::A');
 120
 121 is(Test::A->C_or_D, 'Test::C', '... got the expected method output');
 122 is(Test::A->can('C_or_D')->(), 'Test::C', '... can got the expected method output');
 123
 124 is(Test::A->C_or_E, 'Test::C', '... got the expected method output');
 125 is(Test::A->can('C_or_E')->(), 'Test::C', '... can got the expected method output');
 126
 127 # remove the C3
 128 Class::C3::uninitialize();
 129
 130 is(Test::A->C_or_D, 'Test::D', '...  old method resolution has been restored');
 131 is(Test::A->can('C_or_D')->(), 'Test::D', '...  old can(method) resolution has been restored');
 132
 133 is(Test::A->C_or_E, 'Test::E', '...  old method resolution has been restored');
 134 is(Test::A->can('C_or_E')->(), 'Test::E', '...  old can(method) resolution has been restored');
 135
 136