Add StatementListChanger

src/Statement/StatementListChanger.php

@@ -0,0 +1,69 @@
+<?php
+
+namespace Wikibase\DataModel\Services\Statement;
+
+use Wikibase\DataModel\ByPropertyIdArray;
+use Wikibase\DataModel\Statement\Statement;
+use Wikibase\DataModel\Statement\StatementList;
+
+/**
+ * A collection of functions to manipulate StatementList objects.
+ *
+ * @license GPL-2.0+
+ * @author Thiemo Mättig
+ */
+class StatementListChanger {
+
+	public function clear( StatementList $statementList ) {
+		foreach ( $statementList->toArray() as $statement ) {
+			$statementList->removeStatementsWithGuid( $statement->getGuid() );
+		}
+	}
+
+	/**
+	 * @param StatementList $statementList
+	 * @param Statement[] $statements
+	 */
+	private function replaceStatements( StatementList $statementList, array $statements ) {
+		$this->clear( $statementList );
+
+		foreach ( $statements as $statement ) {
+			$statementList->addStatement( $statement );
+		}
+	}
+
+	public function groupByProperty( StatementList $statementList ) {
+		$byId = [];
+
+		foreach ( $statementList->toArray() as $statement ) {
+			$id = $statement->getPropertyId()->getSerialization();
+			$byId[$id][] = $statement;
+		}
+
+		$this->clear( $statementList );
+
+		foreach ( $byId as $statements ) {
+			foreach ( $statements as $statement ) {
+				$statementList->addStatement( $statement );
+			}
+		}
+	}
+
+	/**
+	 * @param StatementList $statementList
+	 * @param Statement $statement
+	 * @param int $index
+	 */
+	public function addToGroup( StatementList $statementList, Statement $statement, $index ) {
+		if ( $statementList->isEmpty() ) {
+			$statementList->addStatement( $statement );
+			return;
+		}
+
+		$byPropertyIdArray = new ByPropertyIdArray( $statementList->toArray() );
+		$byPropertyIdArray->buildIndex();
+		$byPropertyIdArray->addObjectAtIndex( $statement, $index );
+		$this->replaceStatements( $statementList, $byPropertyIdArray->toFlatArray() );
+	}
+
+}

tests/unit/Statement/StatementListChangerTest.php

@@ -0,0 +1,168 @@
+<?php
+
+namespace Wikibase\DataModel\Services\Tests\Statement;
+
+use PHPUnit_Framework_TestCase;
+use Wikibase\DataModel\Entity\PropertyId;
+use Wikibase\DataModel\Services\Statement\StatementListChanger;
+use Wikibase\DataModel\Snak\PropertyNoValueSnak;
+use Wikibase\DataModel\Statement\Statement;
+use Wikibase\DataModel\Statement\StatementList;
+
+/**
+ * @covers Wikibase\DataModel\Services\Statement\StatementListChanger
+ *
+ * @license GPL-2.0+
+ * @author Thiemo Mättig
+ */
+class StatementListChangerTest extends PHPUnit_Framework_TestCase {
+
+	public function testConstructor() {
+		$instance = new StatementListChanger();
+
+		$this->assertInstanceOf( StatementListChanger::class, $instance );
+	}
+
+	public function testClear() {
+		$statementList = $this->newStatementList( [ 'P1$A' ] );
+
+		$instance = new StatementListChanger();
+		$instance->clear( $statementList );
+
+		$this->assertTrue( $statementList->isEmpty() );
+	}
+
+	/**
+	 * @dataProvider groupByPropertyIdProvider
+	 */
+	public function testGroupByPropertyId( array $guids, array $expectedGuids ) {
+		$statementList = $this->newStatementList( $guids );
+
+		$instance = new StatementListChanger();
+		$instance->groupByProperty( $statementList );
+
+		$this->assertGuids( $expectedGuids, $statementList );
+	}
+
+	public function groupByPropertyIdProvider() {
+		return [
+			[
+				[],
+				[]
+			],
+			[
+				[ 'P1$A' ],
+				[ 'P1$A' ]
+			],
+			[
+				[ 'P1$A', 'P2$B', 'P1$C', 'P2$D' ],
+				[ 'P1$A', 'P1$C', 'P2$B', 'P2$D' ]
+			],
+			[
+				[ 'P1$A', 'P1$B', 'P2$C', 'P3$D', 'P1$E', 'P2$F' ],
+				[ 'P1$A', 'P1$B', 'P1$E', 'P2$C', 'P2$F', 'P3$D' ]
+			],
+		];
+	}
+
+	/**
+	 * @dataProvider addToGroupProvider
+	 */
+	public function testAddToGroup( array $guids, $newGuid, $index, array $expectedGuids ) {
+		$statementList = $this->newStatementList( $guids );
+		$statement = $this->newStatement( $newGuid );
+
+		$instance = new StatementListChanger();
+		$instance->addToGroup( $statementList, $statement, $index );
+
+		$this->assertGuids( $expectedGuids, $statementList );
+	}
+
+	public function addToGroupProvider() {
+		return [
+			'add to empty list' => [
+				[],
+				'P1$A',
+				0,
+				[ 'P1$A' ]
+			],
+			'negative index' => [
+				[],
+				'P1$A',
+				-100,
+				[ 'P1$A' ]
+			],
+			'extreme index' => [
+				[],
+				'P1$A',
+				100,
+				[ 'P1$A' ]
+			],
+			'append one statement' => [
+				[ 'P1$A' ],
+				'P1$B',
+				1,
+				[ 'P1$A', 'P1$B' ]
+			],
+			'prepend one statement' => [
+				[ 'P1$A' ],
+				'P1$B',
+				0,
+				[ 'P1$B', 'P1$A' ]
+			],
+			'insert one statement' => [
+				[ 'P1$A', 'P2$B' ],
+				'P1$C',
+				1,
+				[ 'P1$A', 'P1$C', 'P2$B' ]
+			],
+			'move group to the end' => [
+				[ 'P1$A', 'P2$B' ],
+				'P1$C',
+				100,
+				[ 'P2$B', 'P1$A', 'P1$C' ]
+			],
+		];
+	}
+
+	/**
+	 * @param string[] $guids
+	 *
+	 * @return StatementList
+	 */
+	private function newStatementList( array $guids ) {
+		$statementList = new StatementList();
+
+		foreach ( $guids as $guid ) {
+			$statementList->addStatement( $this->newStatement( $guid ) );
+		}
+
+		return $statementList;
+	}
+
+	private function newStatement( $guid ) {
+		list( $propertyId, ) = explode( '$', $guid, 2 );
+
+		return new Statement(
+			new PropertyNoValueSnak( new PropertyId( $propertyId ) ),
+			null,
+			null,
+			$guid
+		);
+	}
+
+	/**
+	 * @param string[] $expectedGuids
+	 * @param StatementList $statementList
+	 */
+	private function assertGuids( array $expectedGuids, StatementList $statementList ) {
+		$guids = [];
+
+		foreach ( $statementList->toArray() as $statement ) {
+			$guids[] = $statement->getGuid();
+		}
+
+		$this->assertSame( $expectedGuids, $guids );
+	}
+
+}