<?php
  class MySqlDbDistinctFieldTest extends DrupalWebTestCase {
    /**
     * Implementation of getInfo().
     */
    function getInfo() {
      return array(
        'name' => t('Test db_distinct_field in database.mysql.inc'),
        'description' => t('Unit test of db_distinct_field ; see issue http://drupal.org/node/284392'),
        'group' => t('Core'),
      );
    }

    function testPrefixedRewrite() {
      $queries = array(
        array(
          'query'       => 'SELECT node.nid FROM node',
          'expected'    => 'SELECT DISTINCT(node.nid) FROM node',
          'description' => t('Test field prefixed with table is rewritten'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testNonPrefixedRewrite() {
      $queries = array(
        array(
          'query'       => 'SELECT nid FROM node',
          'expected'    => 'SELECT DISTINCT(node.nid) FROM node',
          'description' => t('Test field not prefixed with table is rewritten'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testNotFirstField() {
      $queries = array(
        array(
          'query'       => 'SELECT a, nid, b FROM node',
          'expected'    => 'SELECT a, DISTINCT(node.nid), b FROM node',
          'description' => t('Test query gets rewritten when field is not the first field')
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testMixedCase() {
      $queries = array(
        array(
          'query'       => 'seLecT nId frOm NoDe',
          'expected'    => 'SELECT DISTINCT(node.nid) FROM NoDe',
          'description' => t('Test mixed case spelling field is rewritten'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testPreviousDisctinct() {
      $queries = array(
        array(
          'query'       => 'SELECT DISTINCT(yo), nid FROM node',
          'expected'    => 'SELECT DISTINCT(yo), DISTINCT(node.nid) FROM node',
          'description' => t('Test field is rewritten even with a previous DISTINCT declaration (on another field)'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testNotPrefixedAlreadyDistinct() {
      $queries = array(
        array(
          'query'       => 'SELECT DISTINCT(nid) FROM node',
          'expected'    => 'SELECT DISTINCT(nid) FROM node',
          'description' => t('Test nothing is rewritten when the query already has the DISTINCT with the field name only'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testPrefixedAlreadyDistinct() {
      $queries = array(
        array(
          'query'       => 'SELECT DISTINCT(node.nid) AS nid FROM node',
          'expected'    => 'SELECT DISTINCT(node.nid) AS nid FROM node',
          'description' => t('Test nothing is rewritten when the query already has the DISTINCT with the field prefixed by the table name'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testFieldInAs() {
      $queries = array(
        array(
          'query'       => 'SELECT something AS nid FROM node',
          'expected'    => 'SELECT something AS nid FROM node',
          'description' => t('Test nothing is rewritten when the field name appears in a AS section'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testSubQueryNoTable() {
      $queries = array(
        array(
          'query'       => 'SELECT something FROM other WHERE j IN (SELECT node.nid FROM node)',
          'expected'    => 'SELECT something FROM other WHERE j IN (SELECT node.nid FROM node)',
          'description' => t('Test sub-queries are not rewritten when the table is not present in the main SELECT'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testSubQueryWithTable() {
      $queries = array(
        array(
          'query'       => 'SELECT nid FROM other WHERE j IN (SELECT node.nid FROM node)',
          'expected'    => 'SELECT DISTINCT(node.nid) FROM other WHERE j IN (SELECT node.nid FROM node)',
          'description' => t('Test sub-queries are not rewritten when the table is present in the main SELECT'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testFalseTablePrefix() {
      $queries = array(
        array(
          'query'       => 'SELECT yo_node.nid FROM node',
          'expected'    => 'SELECT yo_node.nid FROM node',
          'description' => t('Test nothing is rewritten when using a table that ends in the name of the table to rewrite'),
        ),
      );
      $this->_testDistinctField($queries);
    }

    function testFalseTableSuffix() {
      $queries = array(
        array(
          'query'       => 'SELECT node.nid_ FROM node',
          'expected'    => 'SELECT node.nid_ FROM node',
          'description' => t('Test queries with fields starting like the one we want to rewrite do not get rewritten'),
        ),
      );

      $this->_testDistinctField($queries);
    }

    function _testDistinctField($queries) {
      foreach ($queries as $q) {
        $r = db_distinct_field('node', 'nid', $q['query']);
        $this->assertEqual($q['expected'], $r, $q['description']);
      }
    }
  }