Introduce IDatabase::buildSubstring

Change-Id: I96f3e0c4920d52f63175cb6767c149f20a8a8cde

diff --git a/includes/db/DatabaseOracle.php b/includes/db/DatabaseOracle.php
index 225a36c..3362f0f 100644 (file)
--- a/includes/db/DatabaseOracle.php
+++ b/includes/db/DatabaseOracle.php
@@ -1358,6 +1358,15 @@ class DatabaseOracle extends Database {
                return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
        }
 
+       public function buildSubstring( $input, $startPosition, $length = null ) {
+               $this->assertBuildSubstringParams( $startPosition, $length );
+               $params = [ $input, $startPosition ];
+               if ( $length !== null ) {
+                       $params[] = $length;
+               }
+               return 'SUBSTR(' . implode( ',', $params ) . ')';
+       }
+
        /**
         * @param string $field Field or column to cast
         * @return string

diff --git a/includes/libs/rdbms/database/DBConnRef.php b/includes/libs/rdbms/database/DBConnRef.php
index ef2953e..910d42f 100644 (file)
--- a/includes/libs/rdbms/database/DBConnRef.php
+++ b/includes/libs/rdbms/database/DBConnRef.php
@@ -350,6 +350,10 @@ class DBConnRef implements IDatabase {
                return $this->__call( __FUNCTION__, func_get_args() );
        }
 
+       public function buildSubstring( $input, $startPosition, $length = null ) {
+               return $this->__call( __FUNCTION__, func_get_args() );
+       }
+
        public function buildStringCast( $field ) {
                return $this->__call( __FUNCTION__, func_get_args() );
        }

diff --git a/includes/libs/rdbms/database/Database.php b/includes/libs/rdbms/database/Database.php
index 8ccccc3..fc0db57 100644 (file)
--- a/includes/libs/rdbms/database/Database.php
+++ b/includes/libs/rdbms/database/Database.php
@@ -1854,6 +1854,40 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
        }
 
+       public function buildSubstring( $input, $startPosition, $length = null ) {
+               $this->assertBuildSubstringParams( $startPosition, $length );
+               $functionBody = "$input FROM $startPosition";
+               if ( $length !== null ) {
+                       $functionBody .= " FOR $length";
+               }
+               return 'SUBSTRING(' . $functionBody . ')';
+       }
+
+       /**
+        * Check type and bounds for parameters to self::buildSubstring()
+        *
+        * All supported databases have substring functions that behave the same for
+        * positive $startPosition and non-negative $length, but behaviors differ when
+        * given 0 or negative $startPosition or negative $length. The simplest
+        * solution to that is to just forbid those values.
+        *
+        * @param int $startPosition
+        * @param int|null $length
+        * @since 1.31
+        */
+       protected function assertBuildSubstringParams( $startPosition, $length ) {
+               if ( !is_int( $startPosition ) || $startPosition <= 0 ) {
+                       throw new InvalidArgumentException(
+                               '$startPosition must be a positive integer'
+                       );
+               }
+               if ( !( is_int( $length ) && $length >= 0 || $length === null ) ) {
+                       throw new InvalidArgumentException(
+                               '$length must be null or an integer greater than or equal to 0'
+                       );
+               }
+       }
+
        public function buildStringCast( $field ) {
                return $field;
        }

diff --git a/includes/libs/rdbms/database/DatabaseMssql.php b/includes/libs/rdbms/database/DatabaseMssql.php
index 771e2e5..b6428c7 100644 (file)
--- a/includes/libs/rdbms/database/DatabaseMssql.php
+++ b/includes/libs/rdbms/database/DatabaseMssql.php
@@ -1225,6 +1225,19 @@ class DatabaseMssql extends Database {
                return $sql;
        }
 
+       public function buildSubstring( $input, $startPosition, $length = null ) {
+               $this->assertBuildSubstringParams( $startPosition, $length );
+               if ( $length === null ) {
+                       /**
+                        * MSSQL doesn't allow an empty length parameter, so when we don't want to limit the
+                        * length returned use the default maximum size of text.
+                        * @see https://docs.microsoft.com/en-us/sql/t-sql/statements/set-textsize-transact-sql
+                        */
+                       $length = 2147483647;
+               }
+               return 'SUBSTRING(' . implode( ',', [ $input, $startPosition, $length ] ) . ')';
+       }
+
        /**
         * Returns an associative array for fields that are of type varbinary, binary, or image
         * $table can be either a raw table name or passed through tableName() first

diff --git a/includes/libs/rdbms/database/DatabaseSqlite.php b/includes/libs/rdbms/database/DatabaseSqlite.php
index 3d6cee3..83c8814 100644 (file)
--- a/includes/libs/rdbms/database/DatabaseSqlite.php
+++ b/includes/libs/rdbms/database/DatabaseSqlite.php
@@ -818,6 +818,15 @@ class DatabaseSqlite extends Database {
                }
        }
 
+       public function buildSubstring( $input, $startPosition, $length = null ) {
+               $this->assertBuildSubstringParams( $startPosition, $length );
+               $params = [ $input, $startPosition ];
+               if ( $length !== null ) {
+                       $params[] = $length;
+               }
+               return 'SUBSTR(' . implode( ',', $params ) . ')';
+       }
+
        /**
         * @param string $field Field or column to cast
         * @return string

diff --git a/includes/libs/rdbms/database/IDatabase.php b/includes/libs/rdbms/database/IDatabase.php
index 9ad78a7..9311c07 100644 (file)
--- a/includes/libs/rdbms/database/IDatabase.php
+++ b/includes/libs/rdbms/database/IDatabase.php
@@ -19,6 +19,7 @@
  */
 namespace Wikimedia\Rdbms;
 
+use InvalidArgumentException;
 use Wikimedia\ScopedCallback;
 use RuntimeException;
 use UnexpectedValueException;
@@ -1050,6 +1051,20 @@ interface IDatabase {
                $delim, $table, $field, $conds = '', $join_conds = []
        );
 
+       /**
+        * Build a SUBSTRING function.
+        *
+        * Behavior for non-ASCII values is undefined.
+        *
+        * @param string $input Field name
+        * @param int $startPosition Positive integer
+        * @param int|null $length Non-negative integer length or null for no limit
+        * @throws InvalidArgumentException
+        * @return string SQL text
+        * @since 1.31
+        */
+       public function buildSubString( $input, $startPosition, $length = null );
+
        /**
         * @param string $field Field or column to cast
         * @return string

diff --git a/tests/phpunit/includes/db/DatabaseOracleTest.php b/tests/phpunit/includes/db/DatabaseOracleTest.php
new file mode 100644 (file)
index 0000000..b03734e
--- /dev/null
+++ b/tests/phpunit/includes/db/DatabaseOracleTest.php
@@ -0,0 +1,51 @@
+<?php
+
+class DatabaseOracleTest extends PHPUnit\Framework\TestCase {
+
+       use MediaWikiCoversValidator;
+
+       /**
+        * @return PHPUnit_Framework_MockObject_MockObject|DatabaseOracle
+        */
+       private function getMockDb() {
+               return $this->getMockBuilder( DatabaseOracle::class )
+                       ->disableOriginalConstructor()
+                       ->setMethods( null )
+                       ->getMock();
+       }
+
+       public function provideBuildSubstring() {
+               yield [ 'someField', 1, 2, 'SUBSTR(someField,1,2)' ];
+               yield [ 'someField', 1, null, 'SUBSTR(someField,1)' ];
+       }
+
+       /**
+        * @covers DatabaseOracle::buildSubstring
+        * @dataProvider provideBuildSubstring
+        */
+       public function testBuildSubstring( $input, $start, $length, $expected ) {
+               $mockDb = $this->getMockDb();
+               $output = $mockDb->buildSubstring( $input, $start, $length );
+               $this->assertSame( $expected, $output );
+       }
+
+       public function provideBuildSubstring_invalidParams() {
+               yield [ -1, 1 ];
+               yield [ 1, -1 ];
+               yield [ 1, 'foo' ];
+               yield [ 'foo', 1 ];
+               yield [ null, 1 ];
+               yield [ 0, 1 ];
+       }
+
+       /**
+        * @covers DatabaseOracle::buildSubstring
+        * @dataProvider provideBuildSubstring_invalidParams
+        */
+       public function testBuildSubstring_invalidParams( $start, $length ) {
+               $mockDb = $this->getMockDb();
+               $this->setExpectedException( InvalidArgumentException::class );
+               $mockDb->buildSubstring( 'foo', $start, $length );
+       }
+
+}

diff --git a/tests/phpunit/includes/db/DatabaseTestHelper.php b/tests/phpunit/includes/db/DatabaseTestHelper.php
index 606c12d..8950152 100644 (file)
--- a/tests/phpunit/includes/db/DatabaseTestHelper.php
+++ b/tests/phpunit/includes/db/DatabaseTestHelper.php
@@ -2,6 +2,7 @@
 
 use Wikimedia\Rdbms\TransactionProfiler;
 use Wikimedia\Rdbms\DatabaseDomain;
+use Wikimedia\Rdbms\Database;
 
 /**
  * Helper for testing the methods from the Database class

diff --git a/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php b/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php
new file mode 100644 (file)
index 0000000..bb85f5a
--- /dev/null
+++ b/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php
@@ -0,0 +1,54 @@
+<?php
+
+use Wikimedia\Rdbms\DatabaseMssql;
+
+class DatabaseMssqlTest extends PHPUnit\Framework\TestCase {
+
+       use MediaWikiCoversValidator;
+
+       /**
+        * @return PHPUnit_Framework_MockObject_MockObject|DatabaseMssql
+        */
+       private function getMockDb() {
+               return $this->getMockBuilder( DatabaseMssql::class )
+                       ->disableOriginalConstructor()
+                       ->setMethods( null )
+                       ->getMock();
+       }
+
+       public function provideBuildSubstring() {
+               yield [ 'someField', 1, 2, 'SUBSTRING(someField,1,2)' ];
+               yield [ 'someField', 1, null, 'SUBSTRING(someField,1,2147483647)' ];
+               yield [ 'someField', 1, 3333333333, 'SUBSTRING(someField,1,3333333333)' ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\DatabaseMssql::buildSubstring
+        * @dataProvider provideBuildSubstring
+        */
+       public function testBuildSubstring( $input, $start, $length, $expected ) {
+               $mockDb = $this->getMockDb();
+               $output = $mockDb->buildSubstring( $input, $start, $length );
+               $this->assertSame( $expected, $output );
+       }
+
+       public function provideBuildSubstring_invalidParams() {
+               yield [ -1, 1 ];
+               yield [ 1, -1 ];
+               yield [ 1, 'foo' ];
+               yield [ 'foo', 1 ];
+               yield [ null, 1 ];
+               yield [ 0, 1 ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\DatabaseMssql::buildSubstring
+        * @dataProvider provideBuildSubstring_invalidParams
+        */
+       public function testBuildSubstring_invalidParams( $start, $length ) {
+               $mockDb = $this->getMockDb();
+               $this->setExpectedException( InvalidArgumentException::class );
+               $mockDb->buildSubstring( 'foo', $start, $length );
+       }
+
+}

diff --git a/tests/phpunit/includes/libs/rdbms/database/DatabaseSQLTest.php b/tests/phpunit/includes/libs/rdbms/database/DatabaseSQLTest.php
index 5c1943b..b3c8cce 100644 (file)
--- a/tests/phpunit/includes/libs/rdbms/database/DatabaseSQLTest.php
+++ b/tests/phpunit/includes/libs/rdbms/database/DatabaseSQLTest.php
@@ -1,5 +1,6 @@
 <?php
 
+use InvalidArgumentException;
 use Wikimedia\Rdbms\LikeMatch;
 
 /**
@@ -1214,4 +1215,38 @@ class DatabaseSQLTest extends PHPUnit\Framework\TestCase {
                $this->assertFalse( $this->database->tableExists( "tmp_table_2", __METHOD__ ) );
                $this->assertFalse( $this->database->tableExists( "tmp_table_3", __METHOD__ ) );
        }
+
+       public function provideBuildSubstring() {
+               yield [ 'someField', 1, 2, 'SUBSTRING(someField FROM 1 FOR 2)' ];
+               yield [ 'someField', 1, null, 'SUBSTRING(someField FROM 1)' ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\Database::buildSubstring
+        * @dataProvider provideBuildSubstring
+        */
+       public function testBuildSubstring( $input, $start, $length, $expected ) {
+               $output = $this->database->buildSubstring( $input, $start, $length );
+               $this->assertSame( $expected, $output );
+       }
+
+       public function provideBuildSubstring_invalidParams() {
+               yield [ -1, 1 ];
+               yield [ 1, -1 ];
+               yield [ 1, 'foo' ];
+               yield [ 'foo', 1 ];
+               yield [ null, 1 ];
+               yield [ 0, 1 ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\Database::buildSubstring
+        * @covers Wikimedia\Rdbms\Database::assertBuildSubstringParams
+        * @dataProvider provideBuildSubstring_invalidParams
+        */
+       public function testBuildSubstring_invalidParams( $start, $length ) {
+               $this->setExpectedException( InvalidArgumentException::class );
+               $this->database->buildSubstring( 'foo', $start, $length );
+       }
+
 }

diff --git a/tests/phpunit/includes/libs/rdbms/database/DatabaseSqliteRdbmsTest.php b/tests/phpunit/includes/libs/rdbms/database/DatabaseSqliteRdbmsTest.php
new file mode 100644 (file)
index 0000000..d963a5d
--- /dev/null
+++ b/tests/phpunit/includes/libs/rdbms/database/DatabaseSqliteRdbmsTest.php
@@ -0,0 +1,59 @@
+<?php
+
+use Wikimedia\Rdbms\DatabaseSqlite;
+
+/**
+ * DatabaseSqliteTest is already defined in mediawiki core hence the 'Rdbms' included in this
+ * class name.
+ * The test in core should have mediawiki specific stuff removed and the tests moved to this
+ * rdbms libs test.
+ */
+class DatabaseSqliteRdbmsTest extends PHPUnit\Framework\TestCase {
+
+       use MediaWikiCoversValidator;
+
+       /**
+        * @return PHPUnit_Framework_MockObject_MockObject|DatabaseSqlite
+        */
+       private function getMockDb() {
+               return $this->getMockBuilder( DatabaseSqlite::class )
+                       ->disableOriginalConstructor()
+                       ->setMethods( null )
+                       ->getMock();
+       }
+
+       public function provideBuildSubstring() {
+               yield [ 'someField', 1, 2, 'SUBSTR(someField,1,2)' ];
+               yield [ 'someField', 1, null, 'SUBSTR(someField,1)' ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\DatabaseSqlite::buildSubstring
+        * @dataProvider provideBuildSubstring
+        */
+       public function testBuildSubstring( $input, $start, $length, $expected ) {
+               $dbMock = $this->getMockDb();
+               $output = $dbMock->buildSubstring( $input, $start, $length );
+               $this->assertSame( $expected, $output );
+       }
+
+       public function provideBuildSubstring_invalidParams() {
+               yield [ -1, 1 ];
+               yield [ 1, -1 ];
+               yield [ 1, 'foo' ];
+               yield [ 'foo', 1 ];
+               yield [ null, 1 ];
+               yield [ 0, 1 ];
+       }
+
+       /**
+        * @covers Wikimedia\Rdbms\DatabaseSqlite::buildSubstring
+        * @dataProvider provideBuildSubstring_invalidParams
+        */
+       public function testBuildSubstring_invalidParams( $start, $length ) {
+               $dbMock = $this->getMockDb();
+               $this->setExpectedException( InvalidArgumentException::class );
+               $dbMock->buildSubstring( 'foo', $start, $length );
+       }
+
+}