search/tests/skip_future_documents_iterator_test.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Test iterator that skips future documents
  19  *
  20  * @package core_search
  21  * @category test
  22  * @copyright 2017 The Open University
  23  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 namespace core_search;
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * Test iterator that skips future documents
  32  *
  33  * @package core_search
  34  * @category test
  35  * @copyright 2017 The Open University
  36  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  37  */
  38 class skip_future_documents_iterator_testcase extends \basic_testcase {
  39
  40     /**
  41      * Test normal case with all documents in the past.
  42      */
  43     public function test_iterator_all_in_past() {
  44         $past = strtotime('2017-11-01');
  45         $documents = [
  46             self::make_doc($past, 1),
  47             self::make_doc($past + 1, 2),
  48             self::make_doc($past + 2, 3)
  49         ];
  50         $this->assertEquals('mod_x-frog-1.mod_x-frog-2.mod_x-frog-3.',
  51                 self::do_iterator($documents));
  52     }
  53
  54     /**
  55      * Confirm that the iterator does not call its parent iterator current() function too many
  56      * times.
  57      */
  58     public function test_iterator_performance() {
  59         $counter = new test_counting_iterator();
  60         $iterator = new skip_future_documents_iterator($counter);
  61         $items = 0;
  62         foreach ($iterator as $value) {
  63             $this->assertEquals(false, $value);
  64             $items++;
  65         }
  66         $this->assertEquals(3, $items);
  67         $this->assertEquals(3, $counter->get_count());
  68     }
  69
  70     /**
  71      * Test with no documents at all.
  72      */
  73     public function test_iterator_empty() {
  74         $this->assertEquals('', self::do_iterator([]));
  75     }
  76
  77     /**
  78      * Test if some documents are in the future.
  79      */
  80     public function test_iterator_some_in_future() {
  81         $past = strtotime('2017-11-01');
  82         $future = time() + 1000;
  83         $documents = [
  84             self::make_doc($past, 1),
  85             self::make_doc($past + 1, 2),
  86             self::make_doc($future, 3)
  87         ];
  88         $this->assertEquals('mod_x-frog-1.mod_x-frog-2.',
  89                 self::do_iterator($documents));
  90     }
  91
  92     /**
  93      * Test if all documents are in the future.
  94      */
  95     public function test_iterator_all_in_future() {
  96         $future = time() + 1000;
  97         $documents = [
  98             self::make_doc($future, 1),
  99             self::make_doc($future + 1, 2),
 100             self::make_doc($future + 2, 3)
 101         ];
 102         $this->assertEquals('', self::do_iterator($documents));
 103     }
 104
 105     /**
 106      * Test when some documents return error.
 107      */
 108     public function test_iterator_some_false() {
 109         $past = strtotime('2017-11-01');
 110         $documents = [
 111             self::make_doc($past, 1),
 112             false,
 113             self::make_doc($past + 2, 3)
 114         ];
 115         $this->assertEquals('mod_x-frog-1.false.mod_x-frog-3.',
 116                 self::do_iterator($documents));
 117     }
 118
 119     /**
 120      * Test when all documents return error.
 121      */
 122     public function test_iterator_all_false() {
 123         $documents = [
 124             false,
 125             false,
 126             false
 127         ];
 128         $this->assertEquals('false.false.false.',
 129                 self::do_iterator($documents));
 130     }
 131
 132     /**
 133      * Test iterator with all cases.
 134      */
 135     public function test_iterator_past_false_and_future() {
 136         $past = strtotime('2017-11-01');
 137         $future = time() + 1000;
 138         $documents = [
 139             false,
 140             self::make_doc($past, 1),
 141             false,
 142             self::make_doc($past + 1, 2),
 143             false,
 144             self::make_doc($future, 3),
 145             false
 146         ];
 147         $this->assertEquals('false.mod_x-frog-1.false.mod_x-frog-2.false.',
 148                 self::do_iterator($documents));
 149     }
 150
 151     /**
 152      * Helper function to create a search document.
 153      *
 154      * @param int $time Modified time
 155      * @param int $index Item id
 156      * @return document Search document
 157      */
 158     protected static function make_doc($time, $index) {
 159         $doc = new document($index, 'mod_x', 'frog');
 160         $doc->set('modified', $time);
 161         return $doc;
 162     }
 163
 164     /**
 165      * Puts documents through the iterator and returns result as a string for easy testing.
 166      *
 167      * @param document[] $documents Array of documents
 168      * @return string Documents converted to string
 169      */
 170     protected static function do_iterator(array $documents) {
 171         $parent = new \ArrayIterator($documents);
 172         $iterator = new skip_future_documents_iterator($parent);
 173         $result = '';
 174         foreach ($iterator as $rec) {
 175             if (!$rec) {
 176                 $result .= 'false.';
 177             } else {
 178                 $result .= $rec->get('id') . '.';
 179             }
 180         }
 181         return $result;
 182     }
 183 }
 184
 185 /**
 186  * Fake iterator just for counting how many times current() is called. It returns 'false' 3 times.
 187  *
 188  * @package core_search
 189  * @category test
 190  * @copyright 2017 The Open University
 191  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 192  */
 193 class test_counting_iterator implements \Iterator {
 194
 195     /** @var int Current position in iterator */
 196     protected $pos = 0;
 197     /** @var int Number of calls to current() function */
 198     protected $count = 0;
 199
 200     /**
 201      * Returns the current element.
 202      *
 203      * @return mixed Can return any type.
 204      */
 205     public function current() {
 206         $this->count++;
 207         return false;
 208     }
 209
 210     /**
 211      * Counts iterator usage.
 212      *
 213      * @return int Number of times current() was called
 214      */
 215     public function get_count() {
 216         return $this->count;
 217     }
 218
 219     /**
 220      * Goes on to the next element.
 221      */
 222     public function next() {
 223         $this->pos++;
 224     }
 225
 226     /**
 227      * Gets the key (not supported)
 228      *
 229      * @throws \coding_exception Always
 230      */
 231     public function key() {
 232         throw new \coding_exception('Unsupported');
 233     }
 234
 235     /**
 236      * Checks if iterato is valid (still has entries).
 237      *
 238      * @return bool True if still valid
 239      */
 240     public function valid() {
 241         return $this->pos < 3;
 242     }
 243
 244     /**
 245      * Rewinds the iterator.
 246      */
 247     public function rewind() {
 248         $this->pos = 0;
 249     }
 250 }