DatabaseTest.php

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<?php
 
use Wikimedia\Rdbms\Database;
use Wikimedia\Rdbms\IDatabase;
use Wikimedia\Rdbms\DatabaseDomain;
use Wikimedia\Rdbms\DatabaseMysqli;
use Wikimedia\Rdbms\LBFactorySingle;
use Wikimedia\Rdbms\TransactionProfiler;
use Wikimedia\TestingAccessWrapper;
use Wikimedia\Rdbms\DatabaseSqlite;
use Wikimedia\Rdbms\DatabasePostgres;
use Wikimedia\Rdbms\DatabaseMssql;
use Wikimedia\Rdbms\DBUnexpectedError;
 
class DatabaseTest extends PHPUnit\Framework\TestCase {
    private $db;
 
    use MediaWikiCoversValidator;
 
    protected function setUp() {
        $this->db = new DatabaseTestHelper( __CLASS__ . '::' . $this->getName() );
    }
 
    public function testFactory() {
        $m = Database::NEW_UNCONNECTED; // no-connect mode
        $p = [ 'host' => 'localhost', 'user' => 'me', 'password' => 'myself', 'dbname' => 'i' ];
 
        $this->assertInstanceOf( DatabaseMysqli::class, Database::factory( 'mysqli', $p, $m ) );
        $this->assertInstanceOf( DatabaseMysqli::class, Database::factory( 'MySqli', $p, $m ) );
        $this->assertInstanceOf( DatabaseMysqli::class, Database::factory( 'MySQLi', $p, $m ) );
        $this->assertInstanceOf( DatabasePostgres::class, Database::factory( 'postgres', $p, $m ) );
        $this->assertInstanceOf( DatabasePostgres::class, Database::factory( 'Postgres', $p, $m ) );
 
        $x = $p + [ 'port' => 10000, 'UseWindowsAuth' => false ];
        $this->assertInstanceOf( DatabaseMssql::class, Database::factory( 'mssql', $x, $m ) );
 
        $x = $p + [ 'dbFilePath' => 'some/file.sqlite' ];
        $this->assertInstanceOf( DatabaseSqlite::class, Database::factory( 'sqlite', $x, $m ) );
        $x = $p + [ 'dbDirectory' => 'some/file' ];
        $this->assertInstanceOf( DatabaseSqlite::class, Database::factory( 'sqlite', $x, $m ) );
    }
 
    public static function provideAddQuotes() {
        return [
            [ null, 'NULL' ],
            [ 1234, "'1234'" ],
            [ 1234.5678, "'1234.5678'" ],
            [ 'string', "'string'" ],
            [ 'string\'s cause trouble', "'string\'s cause trouble'" ],
        ];
    }
 
    public function testAddQuotes( $input, $expected ) {
        $this->assertEquals( $expected, $this->db->addQuotes( $input ) );
    }
 
    public static function provideTableName() {
        // Formatting is mostly ignored since addIdentifierQuotes is abstract.
        // For testing of addIdentifierQuotes, see actual Database subclas tests.
        return [
            'local' => [
                'tablename',
                'tablename',
                'quoted',
            ],
            'local-raw' => [
                'tablename',
                'tablename',
                'raw',
            ],
            'shared' => [
                'sharedb.tablename',
                'tablename',
                'quoted',
                [ 'dbname' => 'sharedb', 'schema' => null, 'prefix' => '' ],
            ],
            'shared-raw' => [
                'sharedb.tablename',
                'tablename',
                'raw',
                [ 'dbname' => 'sharedb', 'schema' => null, 'prefix' => '' ],
            ],
            'shared-prefix' => [
                'sharedb.sh_tablename',
                'tablename',
                'quoted',
                [ 'dbname' => 'sharedb', 'schema' => null, 'prefix' => 'sh_' ],
            ],
            'shared-prefix-raw' => [
                'sharedb.sh_tablename',
                'tablename',
                'raw',
                [ 'dbname' => 'sharedb', 'schema' => null, 'prefix' => 'sh_' ],
            ],
            'foreign' => [
                'databasename.tablename',
                'databasename.tablename',
                'quoted',
            ],
            'foreign-raw' => [
                'databasename.tablename',
                'databasename.tablename',
                'raw',
            ],
        ];
    }
 
    public function testTableName( $expected, $table, $format, array $alias = null ) {
        if ( $alias ) {
            $this->db->setTableAliases( [ $table => $alias ] );
        }
        $this->assertEquals(
            $expected,
            $this->db->tableName( $table, $format ?: 'quoted' )
        );
    }
 
    public function provideTableNamesWithIndexClauseOrJOIN() {
        return [
            'one-element array' => [
                [ 'table' ], [], 'table '
            ],
            'comma join' => [
                [ 'table1', 'table2' ], [], 'table1,table2 '
            ],
            'real join' => [
                [ 'table1', 'table2' ],
                [ 'table2' => [ 'LEFT JOIN', 't1_id = t2_id' ] ],
                'table1 LEFT JOIN table2 ON ((t1_id = t2_id))'
            ],
            'real join with multiple conditionals' => [
                [ 'table1', 'table2' ],
                [ 'table2' => [ 'LEFT JOIN', [ 't1_id = t2_id', 't2_x = \'X\'' ] ] ],
                'table1 LEFT JOIN table2 ON ((t1_id = t2_id) AND (t2_x = \'X\'))'
            ],
            'join with parenthesized group' => [
                [ 'table1', 'n' => [ 'table2', 'table3' ] ],
                [
                    'table3' => [ 'JOIN', 't2_id = t3_id' ],
                    'n' => [ 'LEFT JOIN', 't1_id = t2_id' ],
                ],
                'table1 LEFT JOIN (table2 JOIN table3 ON ((t2_id = t3_id))) ON ((t1_id = t2_id))'
            ],
            'join with degenerate parenthesized group' => [
                [ 'table1', 'n' => [ 't2' => 'table2' ] ],
                [
                    'n' => [ 'LEFT JOIN', 't1_id = t2_id' ],
                ],
                'table1 LEFT JOIN table2 t2 ON ((t1_id = t2_id))'
            ],
        ];
    }
 
    public function testTableNamesWithIndexClauseOrJOIN( $tables, $join_conds, $expect ) {
        $clause = TestingAccessWrapper::newFromObject( $this->db )
            ->tableNamesWithIndexClauseOrJOIN( $tables, [], [], $join_conds );
        $this->assertSame( $expect, $clause );
    }
 
    public function testTransactionIdle() {
        $db = $this->db;
 
        $db->clearFlag( DBO_TRX );
        $called = false;
        $flagSet = null;
        $callback = function ( $trigger, IDatabase $db ) use ( &$flagSet, &$called ) {
            $called = true;
            $flagSet = $db->getFlag( DBO_TRX );
        };
 
        $db->onTransactionCommitOrIdle( $callback, __METHOD__ );
        $this->assertTrue( $called, 'Callback reached' );
        $this->assertFalse( $flagSet, 'DBO_TRX off in callback' );
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX still default' );
 
        $flagSet = null;
        $called = false;
        $db->startAtomic( __METHOD__ );
        $db->onTransactionCommitOrIdle( $callback, __METHOD__ );
        $this->assertFalse( $called, 'Callback not reached during TRX' );
        $db->endAtomic( __METHOD__ );
 
        $this->assertTrue( $called, 'Callback reached after COMMIT' );
        $this->assertFalse( $flagSet, 'DBO_TRX off in callback' );
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX restored to default' );
 
        $db->clearFlag( DBO_TRX );
        $db->onTransactionCommitOrIdle(
            function ( $trigger, IDatabase $db ) {
                $db->setFlag( DBO_TRX );
            },
            __METHOD__
        );
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX restored to default' );
    }
 
    public function testTransactionIdle_TRX() {
        $db = $this->getMockDB( [ 'isOpen', 'ping', 'getDBname' ] );
        $db->method( 'isOpen' )->willReturn( true );
        $db->method( 'ping' )->willReturn( true );
        $db->method( 'getDBname' )->willReturn( '' );
        $db->setFlag( DBO_TRX );
 
        $lbFactory = LBFactorySingle::newFromConnection( $db );
        // Ask for the connection so that LB sets internal state
        // about this connection being the master connection
        $lb = $lbFactory->getMainLB();
        $conn = $lb->openConnection( $lb->getWriterIndex() );
        $this->assertSame( $db, $conn, 'Same DB instance' );
        $this->assertTrue( $db->getFlag( DBO_TRX ), 'DBO_TRX is set' );
 
        $called = false;
        $flagSet = null;
        $callback = function () use ( $db, &$flagSet, &$called ) {
            $called = true;
            $flagSet = $db->getFlag( DBO_TRX );
        };
 
        $db->onTransactionCommitOrIdle( $callback, __METHOD__ );
        $this->assertTrue( $called, 'Called when idle if DBO_TRX is set' );
        $this->assertFalse( $flagSet, 'DBO_TRX off in callback' );
        $this->assertTrue( $db->getFlag( DBO_TRX ), 'DBO_TRX still default' );
 
        $called = false;
        $lbFactory->beginMasterChanges( __METHOD__ );
        $db->onTransactionCommitOrIdle( $callback, __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is active' );
 
        $lbFactory->commitMasterChanges( __METHOD__ );
        $this->assertTrue( $called, 'Called when lb-transaction is committed' );
 
        $called = false;
        $lbFactory->beginMasterChanges( __METHOD__ );
        $db->onTransactionCommitOrIdle( $callback, __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is active' );
 
        $lbFactory->rollbackMasterChanges( __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is rolled back' );
 
        $lbFactory->commitMasterChanges( __METHOD__ );
        $this->assertFalse( $called, 'Not called in next round commit' );
 
        $db->setFlag( DBO_TRX );
        try {
            $db->onTransactionCommitOrIdle( function () {
                throw new RuntimeException( 'test' );
            } );
            $this->fail( "Exception not thrown" );
        } catch ( RuntimeException $e ) {
            $this->assertTrue( $db->getFlag( DBO_TRX ) );
        }
    }
 
    public function testTransactionPreCommitOrIdle() {
        $db = $this->getMockDB( [ 'isOpen' ] );
        $db->method( 'isOpen' )->willReturn( true );
        $db->clearFlag( DBO_TRX );
 
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX is not set' );
 
        $called = false;
        $db->onTransactionPreCommitOrIdle(
            function ( IDatabase $db ) use ( &$called ) {
                $called = true;
            },
            __METHOD__
        );
        $this->assertTrue( $called, 'Called when idle' );
 
        $db->begin( __METHOD__ );
        $called = false;
        $db->onTransactionPreCommitOrIdle(
            function ( IDatabase $db ) use ( &$called ) {
                $called = true;
            },
            __METHOD__
        );
        $this->assertFalse( $called, 'Not called when transaction is active' );
        $db->commit( __METHOD__ );
        $this->assertTrue( $called, 'Called when transaction is committed' );
    }
 
    public function testTransactionPreCommitOrIdle_TRX() {
        $db = $this->getMockDB( [ 'isOpen', 'ping', 'getDBname' ] );
        $db->method( 'isOpen' )->willReturn( true );
        $db->method( 'ping' )->willReturn( true );
        $db->method( 'getDBname' )->willReturn( 'unittest' );
        $db->setFlag( DBO_TRX );
 
        $lbFactory = LBFactorySingle::newFromConnection( $db );
        // Ask for the connection so that LB sets internal state
        // about this connection being the master connection
        $lb = $lbFactory->getMainLB();
        $conn = $lb->openConnection( $lb->getWriterIndex() );
        $this->assertSame( $db, $conn, 'Same DB instance' );
 
        $this->assertFalse( $lb->hasMasterChanges() );
        $this->assertTrue( $db->getFlag( DBO_TRX ), 'DBO_TRX is set' );
        $called = false;
        $callback = function ( IDatabase $db ) use ( &$called ) {
            $called = true;
        };
        $db->onTransactionPreCommitOrIdle( $callback, __METHOD__ );
        $this->assertTrue( $called, 'Called when idle if DBO_TRX is set' );
        $called = false;
        $lbFactory->commitMasterChanges();
        $this->assertFalse( $called );
 
        $called = false;
        $lbFactory->beginMasterChanges( __METHOD__ );
        $db->onTransactionPreCommitOrIdle( $callback, __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is active' );
        $lbFactory->commitMasterChanges( __METHOD__ );
        $this->assertTrue( $called, 'Called when lb-transaction is committed' );
 
        $called = false;
        $lbFactory->beginMasterChanges( __METHOD__ );
        $db->onTransactionPreCommitOrIdle( $callback, __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is active' );
 
        $lbFactory->rollbackMasterChanges( __METHOD__ );
        $this->assertFalse( $called, 'Not called when lb-transaction is rolled back' );
 
        $lbFactory->commitMasterChanges( __METHOD__ );
        $this->assertFalse( $called, 'Not called in next round commit' );
    }
 
    public function testTransactionResolution() {
        $db = $this->db;
 
        $db->clearFlag( DBO_TRX );
        $db->begin( __METHOD__ );
        $called = false;
        $db->onTransactionResolution( function ( $trigger, IDatabase $db ) use ( &$called ) {
            $called = true;
            $db->setFlag( DBO_TRX );
        } );
        $db->commit( __METHOD__ );
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX restored to default' );
        $this->assertTrue( $called, 'Callback reached' );
 
        $db->clearFlag( DBO_TRX );
        $db->begin( __METHOD__ );
        $called = false;
        $db->onTransactionResolution( function ( $trigger, IDatabase $db ) use ( &$called ) {
            $called = true;
            $db->setFlag( DBO_TRX );
        } );
        $db->rollback( __METHOD__ );
        $this->assertFalse( $db->getFlag( DBO_TRX ), 'DBO_TRX restored to default' );
        $this->assertTrue( $called, 'Callback reached' );
    }
 
    public function testTransactionListener() {
        $db = $this->db;
 
        $db->setTransactionListener( 'ping', function () use ( $db, &$called ) {
            $called = true;
        } );
 
        $called = false;
        $db->begin( __METHOD__ );
        $db->commit( __METHOD__ );
        $this->assertTrue( $called, 'Callback reached' );
 
        $called = false;
        $db->begin( __METHOD__ );
        $db->commit( __METHOD__ );
        $this->assertTrue( $called, 'Callback still reached' );
 
        $called = false;
        $db->begin( __METHOD__ );
        $db->rollback( __METHOD__ );
        $this->assertTrue( $called, 'Callback reached' );
 
        $db->setTransactionListener( 'ping', null );
        $called = false;
        $db->begin( __METHOD__ );
        $db->commit( __METHOD__ );
        $this->assertFalse( $called, 'Callback not reached' );
    }
 
    private function getMockDB( $methods = [] ) {
        static $abstractMethods = [
            'fetchAffectedRowCount',
            'closeConnection',
            'dataSeek',
            'doQuery',
            'fetchObject', 'fetchRow',
            'fieldInfo', 'fieldName',
            'getSoftwareLink', 'getServerVersion',
            'getType',
            'indexInfo',
            'insertId',
            'lastError', 'lastErrno',
            'numFields', 'numRows',
            'open',
            'strencode',
            'tableExists'
        ];
        $db = $this->getMockBuilder( Database::class )
            ->disableOriginalConstructor()
            ->setMethods( array_values( array_unique( array_merge(
                $abstractMethods,
                $methods
            ) ) ) )
            ->getMock();
        $wdb = TestingAccessWrapper::newFromObject( $db );
        $wdb->trxProfiler = new TransactionProfiler();
        $wdb->connLogger = new \Psr\Log\NullLogger();
        $wdb->queryLogger = new \Psr\Log\NullLogger();
        $wdb->currentDomain = DatabaseDomain::newUnspecified();
        return $db;
    }
 
    public function testFlushSnapshot() {
        $db = $this->getMockDB( [ 'isOpen' ] );
        $db->method( 'isOpen' )->willReturn( true );
 
        $db->flushSnapshot( __METHOD__ ); // ok
        $db->flushSnapshot( __METHOD__ ); // ok
 
        $db->setFlag( DBO_TRX, $db::REMEMBER_PRIOR );
        $db->query( 'SELECT 1', __METHOD__ );
        $this->assertTrue( (bool)$db->trxLevel(), "Transaction started." );
        $db->flushSnapshot( __METHOD__ ); // ok
        $db->restoreFlags( $db::RESTORE_PRIOR );
 
        $this->assertFalse( (bool)$db->trxLevel(), "Transaction cleared." );
    }
 
    public function testGetScopedLock() {
        $db = $this->getMockDB( [ 'isOpen', 'getDBname' ] );
        $db->method( 'isOpen' )->willReturn( true );
        $db->method( 'getDBname' )->willReturn( 'unittest' );
 
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertEquals( true, $db->lockIsFree( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->lock( 'x', __METHOD__ ) );
        $this->assertEquals( false, $db->lockIsFree( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->unlock( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->lockIsFree( 'x', __METHOD__ ) );
        $this->assertEquals( 0, $db->trxLevel() );
 
        $db->setFlag( DBO_TRX );
        $this->assertEquals( true, $db->lockIsFree( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->lock( 'x', __METHOD__ ) );
        $this->assertEquals( false, $db->lockIsFree( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->unlock( 'x', __METHOD__ ) );
        $this->assertEquals( true, $db->lockIsFree( 'x', __METHOD__ ) );
        $db->clearFlag( DBO_TRX );
 
        // Pending writes with DBO_TRX
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertTrue( $db->lockIsFree( 'meow', __METHOD__ ) );
        $db->setFlag( DBO_TRX );
        $db->query( "DELETE FROM test WHERE t = 1" ); // trigger DBO_TRX transaction before lock
        try {
            $lock = $db->getScopedLockAndFlush( 'meow', __METHOD__, 1 );
            $this->fail( "Exception not reached" );
        } catch ( DBUnexpectedError $e ) {
            $this->assertEquals( 1, $db->trxLevel(), "Transaction not committed." );
            $this->assertTrue( $db->lockIsFree( 'meow', __METHOD__ ), 'Lock not acquired' );
        }
        $db->rollback( __METHOD__, IDatabase::FLUSHING_ALL_PEERS );
        // Pending writes without DBO_TRX
        $db->clearFlag( DBO_TRX );
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertTrue( $db->lockIsFree( 'meow2', __METHOD__ ) );
        $db->begin( __METHOD__ );
        $db->query( "DELETE FROM test WHERE t = 1" ); // trigger DBO_TRX transaction before lock
        try {
            $lock = $db->getScopedLockAndFlush( 'meow2', __METHOD__, 1 );
            $this->fail( "Exception not reached" );
        } catch ( DBUnexpectedError $e ) {
            $this->assertEquals( 1, $db->trxLevel(), "Transaction not committed." );
            $this->assertTrue( $db->lockIsFree( 'meow2', __METHOD__ ), 'Lock not acquired' );
        }
        $db->rollback( __METHOD__ );
        // No pending writes, with DBO_TRX
        $db->setFlag( DBO_TRX );
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertTrue( $db->lockIsFree( 'wuff', __METHOD__ ) );
        $db->query( "SELECT 1", __METHOD__ );
        $this->assertEquals( 1, $db->trxLevel() );
        $lock = $db->getScopedLockAndFlush( 'wuff', __METHOD__, 1 );
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertFalse( $db->lockIsFree( 'wuff', __METHOD__ ), 'Lock already acquired' );
        $db->rollback( __METHOD__, IDatabase::FLUSHING_ALL_PEERS );
        // No pending writes, without DBO_TRX
        $db->clearFlag( DBO_TRX );
        $this->assertEquals( 0, $db->trxLevel() );
        $this->assertTrue( $db->lockIsFree( 'wuff2', __METHOD__ ) );
        $db->begin( __METHOD__ );
        try {
            $lock = $db->getScopedLockAndFlush( 'wuff2', __METHOD__, 1 );
            $this->fail( "Exception not reached" );
        } catch ( DBUnexpectedError $e ) {
            $this->assertEquals( 1, $db->trxLevel(), "Transaction not committed." );
            $this->assertFalse( $db->lockIsFree( 'wuff2', __METHOD__ ), 'Lock not acquired' );
        }
        $db->rollback( __METHOD__ );
    }
 
    public function testFlagSetting() {
        $db = $this->db;
        $origTrx = $db->getFlag( DBO_TRX );
        $origSsl = $db->getFlag( DBO_SSL );
 
        $origTrx
            ? $db->clearFlag( DBO_TRX, $db::REMEMBER_PRIOR )
            : $db->setFlag( DBO_TRX, $db::REMEMBER_PRIOR );
        $this->assertEquals( !$origTrx, $db->getFlag( DBO_TRX ) );
 
        $origSsl
            ? $db->clearFlag( DBO_SSL, $db::REMEMBER_PRIOR )
            : $db->setFlag( DBO_SSL, $db::REMEMBER_PRIOR );
        $this->assertEquals( !$origSsl, $db->getFlag( DBO_SSL ) );
 
        $db->restoreFlags( $db::RESTORE_INITIAL );
        $this->assertEquals( $origTrx, $db->getFlag( DBO_TRX ) );
        $this->assertEquals( $origSsl, $db->getFlag( DBO_SSL ) );
 
        $origTrx
            ? $db->clearFlag( DBO_TRX, $db::REMEMBER_PRIOR )
            : $db->setFlag( DBO_TRX, $db::REMEMBER_PRIOR );
        $origSsl
            ? $db->clearFlag( DBO_SSL, $db::REMEMBER_PRIOR )
            : $db->setFlag( DBO_SSL, $db::REMEMBER_PRIOR );
 
        $db->restoreFlags();
        $this->assertEquals( $origSsl, $db->getFlag( DBO_SSL ) );
        $this->assertEquals( !$origTrx, $db->getFlag( DBO_TRX ) );
 
        $db->restoreFlags();
        $this->assertEquals( $origSsl, $db->getFlag( DBO_SSL ) );
        $this->assertEquals( $origTrx, $db->getFlag( DBO_TRX ) );
    }
 
    public function testDBOIgnoreSet() {
        $db = $this->getMockBuilder( DatabaseMysqli::class )
            ->disableOriginalConstructor()
            ->setMethods( null )
            ->getMock();
 
        $db->setFlag( Database::DBO_IGNORE );
    }
 
    public function testDBOIgnoreClear() {
        $db = $this->getMockBuilder( DatabaseMysqli::class )
            ->disableOriginalConstructor()
            ->setMethods( null )
            ->getMock();
 
        $db->clearFlag( Database::DBO_IGNORE );
    }
 
    public function testSchemaAndPrefixMutators() {
        $ud = DatabaseDomain::newUnspecified();
 
        $this->assertEquals( $ud->getId(), $this->db->getDomainID() );
 
        $old = $this->db->tablePrefix();
        $oldDomain = $this->db->getDomainId();
        $this->assertInternalType( 'string', $old, 'Prefix is string' );
        $this->assertSame( $old, $this->db->tablePrefix(), "Prefix unchanged" );
        $this->assertSame( $old, $this->db->tablePrefix( 'xxx_' ) );
        $this->assertSame( 'xxx_', $this->db->tablePrefix(), "Prefix set" );
        $this->db->tablePrefix( $old );
        $this->assertNotEquals( 'xxx_', $this->db->tablePrefix() );
        $this->assertSame( $oldDomain, $this->db->getDomainId() );
 
        $old = $this->db->dbSchema();
        $oldDomain = $this->db->getDomainId();
        $this->assertInternalType( 'string', $old, 'Schema is string' );
        $this->assertSame( $old, $this->db->dbSchema(), "Schema unchanged" );
 
        $this->db->selectDB( 'y' );
        $this->assertSame( $old, $this->db->dbSchema( 'xxx' ) );
        $this->assertSame( 'xxx', $this->db->dbSchema(), "Schema set" );
        $this->db->dbSchema( $old );
        $this->assertNotEquals( 'xxx', $this->db->dbSchema() );
        $this->assertSame( "y", $this->db->getDomainId() );
    }
 
    public function testSchemaWithNoDB() {
        $ud = DatabaseDomain::newUnspecified();
 
        $this->assertEquals( $ud->getId(), $this->db->getDomainID() );
        $this->assertSame( '', $this->db->dbSchema() );
 
        $this->db->dbSchema( 'xxx' );
    }
 
    public function testSelectDomain() {
        $oldDomain = $this->db->getDomainId();
        $oldDatabase = $this->db->getDBname();
        $oldSchema = $this->db->dbSchema();
        $oldPrefix = $this->db->tablePrefix();
 
        $this->db->selectDomain( 'testselectdb-xxx_' );
        $this->assertSame( 'testselectdb', $this->db->getDBname() );
        $this->assertSame( '', $this->db->dbSchema() );
        $this->assertSame( 'xxx_', $this->db->tablePrefix() );
 
        $this->db->selectDomain( $oldDomain );
        $this->assertSame( $oldDatabase, $this->db->getDBname() );
        $this->assertSame( $oldSchema, $this->db->dbSchema() );
        $this->assertSame( $oldPrefix, $this->db->tablePrefix() );
        $this->assertSame( $oldDomain, $this->db->getDomainId() );
 
        $this->db->selectDomain( 'testselectdb-schema-xxx_' );
        $this->assertSame( 'testselectdb', $this->db->getDBname() );
        $this->assertSame( 'schema', $this->db->dbSchema() );
        $this->assertSame( 'xxx_', $this->db->tablePrefix() );
 
        $this->db->selectDomain( $oldDomain );
        $this->assertSame( $oldDatabase, $this->db->getDBname() );
        $this->assertSame( $oldSchema, $this->db->dbSchema() );
        $this->assertSame( $oldPrefix, $this->db->tablePrefix() );
        $this->assertSame( $oldDomain, $this->db->getDomainId() );
    }
 
}