API: Overhaul ApiResult, make format=xml not throw, and add json formatversion

ApiResult was a mess: some methods could only be used with an array
reference instead of manipulating the stored data, methods that had both
array-ref and internal-data versions had names that didn't at all
correspond, some methods that worked on an array reference were
annoyingly non-static, and then the whole mess with setIndexedTagName.

ApiFormatXml is also entirely annoying to deal with, as it liked to
throw exceptions if certain metadata wasn't provided that no other
formatter required. Its legacy also means we have this silly convention
of using empty-string rather than boolean true, annoying restrictions on
keys (leading to things that should be hashes being arrays of key-value
object instead), '*' used as a key all over the place, and so on.

So, changes here:
* ApiResult is no longer an ApiBase or a ContextSource.
* Wherever sensible, ApiResult provides a static method working on an
  arrayref and a non-static method working on internal data.
* Metadata is now always added to ApiResult's internal data structure.
  Formatters are responsible for stripping it if necessary. "raw mode"
  is deprecated.
* New metadata to replace the '*' key, solve the array() => '[]' vs '{}'
  question, and so on.
* New class for formatting warnings and errors using i18n messages, and
  support for multiple errors and a more machine-readable format for
  warnings. For the moment, though, the actual output will not be changing
  yet (see T47843 for future plans).
* New formatversion parameter for format=json and format=php, to select
  between BC mode and the modern output.
* In BC mode, booleans will be converted to empty-string presence style;
  modules currently returning booleans will need to use
  ApiResult::META_BC_BOOLS to preserve their current output.

Actual changes to the API modules' output (e.g. actually returning
booleans for the new formatversion) beyond the use of
ApiResult::setContentValue() are left for a future change.

Bug: T76728
Bug: T57371
Bug: T33629
Change-Id: I7b37295e8862b188d1f3b0cd07f66ac34629678f

1 files changed, 1446 insertions, 0 deletions

diff --git a/tests/phpunit/includes/api/ApiResultTest.php b/tests/phpunit/includes/api/ApiResultTest.php
new file mode 100644
index 000000000000..7e43a240a718
--- /dev/null
+++ b/tests/phpunit/includes/api/ApiResultTest.php
@@ -0,0 +1,1446 @@
+<?php
+
+/**
+ * @covers ApiResult
+ * @group API
+ */
+class ApiResultTest extends MediaWikiTestCase {
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testStaticDataMethods() {
+		$arr = array();
+
+		ApiResult::setValue( $arr, 'setValue', '1' );
+
+		ApiResult::setValue( $arr, null, 'unnamed 1' );
+		ApiResult::setValue( $arr, null, 'unnamed 2' );
+
+		ApiResult::setValue( $arr, 'deleteValue', '2' );
+		ApiResult::unsetValue( $arr, 'deleteValue' );
+
+		ApiResult::setContentValue( $arr, 'setContentValue', '3' );
+
+		$this->assertSame( array(
+			'setValue' => '1',
+			'unnamed 1',
+			'unnamed 2',
+			ApiResult::META_CONTENT => 'setContentValue',
+			'setContentValue' => '3',
+		), $arr );
+
+		try {
+			ApiResult::setValue( $arr, 'setValue', '99' );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Attempting to add element setValue=99, existing value is 1',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		try {
+			ApiResult::setContentValue( $arr, 'setContentValue2', '99' );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Attempting to set content element as setContentValue2 when setContentValue ' .
+					'is already set as the content element',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		ApiResult::setValue( $arr, 'setValue', '99', ApiResult::OVERRIDE );
+		$this->assertSame( '99', $arr['setValue'] );
+
+		ApiResult::setContentValue( $arr, 'setContentValue2', '99', ApiResult::OVERRIDE );
+		$this->assertSame( 'setContentValue2', $arr[ApiResult::META_CONTENT] );
+
+		$arr = array( 'foo' => 1, 'bar' => 1 );
+		ApiResult::setValue( $arr, 'top', '2', ApiResult::ADD_ON_TOP );
+		ApiResult::setValue( $arr, null, '2', ApiResult::ADD_ON_TOP );
+		ApiResult::setValue( $arr, 'bottom', '2' );
+		ApiResult::setValue( $arr, 'foo', '2', ApiResult::OVERRIDE );
+		ApiResult::setValue( $arr, 'bar', '2', ApiResult::OVERRIDE | ApiResult::ADD_ON_TOP );
+		$this->assertSame( array( 0, 'top', 'foo', 'bar', 'bottom' ), array_keys( $arr ) );
+
+		$arr = array();
+		ApiResult::setValue( $arr, 'sub', array( 'foo' => 1 ) );
+		ApiResult::setValue( $arr, 'sub', array( 'bar' => 1 ) );
+		$this->assertSame( array( 'sub' => array( 'foo' => 1, 'bar' => 1 ) ), $arr );
+
+		try {
+			ApiResult::setValue( $arr, 'sub', array( 'foo' => 2, 'baz' => 2 ) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Conflicting keys (foo) when attempting to merge element sub',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$arr = array();
+		$title = Title::newFromText( "MediaWiki:Foobar" );
+		$obj = new stdClass;
+		$obj->foo = 1;
+		$obj->bar = 2;
+		ApiResult::setValue( $arr, 'title', $title );
+		ApiResult::setValue( $arr, 'obj', $obj );
+		$this->assertSame( array(
+			'title' => (string)$title,
+			'obj' => array( 'foo' => 1, 'bar' => 2, ApiResult::META_TYPE => 'assoc' ),
+		), $arr );
+
+		$fh = tmpfile();
+		try {
+			ApiResult::setValue( $arr, 'file', $fh );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add resource(stream) to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		try {
+			$obj->file = $fh;
+			ApiResult::setValue( $arr, 'sub', $obj );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add resource(stream) to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		fclose( $fh );
+
+		try {
+			ApiResult::setValue( $arr, 'inf', INF );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add non-finite floats to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		try {
+			ApiResult::setValue( $arr, 'nan', NAN );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add non-finite floats to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$arr = array();
+		$result2 = new ApiResult( 8388608 );
+		$result2->addValue( null, 'foo', 'bar' );
+		ApiResult::setValue( $arr, 'baz', $result2 );
+		$this->assertSame( array( 'baz' => array( 'foo' => 'bar' ) ), $arr );
+
+		$arr = array();
+		ApiResult::setValue( $arr, 'foo', "foo\x80bar" );
+		ApiResult::setValue( $arr, 'bar', "a\xcc\x81" );
+		ApiResult::setValue( $arr, 'baz', 74 );
+		$this->assertSame( array(
+			'foo' => "foo\xef\xbf\xbdbar",
+			'bar' => "\xc3\xa1",
+			'baz' => 74,
+		), $arr );
+	}
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testInstanceDataMethods() {
+		$result = new ApiResult( 8388608 );
+
+		$result->addValue( null, 'setValue', '1' );
+
+		$result->addValue( null, null, 'unnamed 1' );
+		$result->addValue( null, null, 'unnamed 2' );
+
+		$result->addValue( null, 'deleteValue', '2' );
+		$result->removeValue( null, 'deleteValue' );
+
+		$result->addValue( array( 'a', 'b' ), 'deleteValue', '3' );
+		$result->removeValue( array( 'a', 'b', 'deleteValue' ), null, '3' );
+
+		$result->addContentValue( null, 'setContentValue', '3' );
+
+		$this->assertSame( array(
+			'setValue' => '1',
+			'unnamed 1',
+			'unnamed 2',
+			'a' => array( 'b' => array() ),
+			'setContentValue' => '3',
+			ApiResult::META_CONTENT => 'setContentValue',
+		), $result->getResultData() );
+		$this->assertSame( 20, $result->getSize() );
+
+		try {
+			$result->addValue( null, 'setValue', '99' );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Attempting to add element setValue=99, existing value is 1',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		try {
+			$result->addContentValue( null, 'setContentValue2', '99' );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Attempting to set content element as setContentValue2 when setContentValue ' .
+					'is already set as the content element',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$result->addValue( null, 'setValue', '99', ApiResult::OVERRIDE );
+		$this->assertSame( '99', $result->getResultData( array( 'setValue' ) ) );
+
+		$result->addContentValue( null, 'setContentValue2', '99', ApiResult::OVERRIDE );
+		$this->assertSame( 'setContentValue2',
+			$result->getResultData( array( ApiResult::META_CONTENT ) ) );
+
+		$result->reset();
+		$this->assertSame( array(), $result->getResultData() );
+		$this->assertSame( 0, $result->getSize() );
+
+		$result->addValue( null, 'foo', 1 );
+		$result->addValue( null, 'bar', 1 );
+		$result->addValue( null, 'top', '2', ApiResult::ADD_ON_TOP );
+		$result->addValue( null, null, '2', ApiResult::ADD_ON_TOP );
+		$result->addValue( null, 'bottom', '2' );
+		$result->addValue( null, 'foo', '2', ApiResult::OVERRIDE );
+		$result->addValue( null, 'bar', '2', ApiResult::OVERRIDE | ApiResult::ADD_ON_TOP );
+		$this->assertSame( array( 0, 'top', 'foo', 'bar', 'bottom' ),
+			array_keys( $result->getResultData() ) );
+
+		$result->reset();
+		$result->addValue( null, 'foo', array( 'bar' => 1 ) );
+		$result->addValue( array( 'foo', 'top' ), 'x', 2, ApiResult::ADD_ON_TOP );
+		$result->addValue( array( 'foo', 'bottom' ), 'x', 2 );
+		$this->assertSame( array( 'top', 'bar', 'bottom' ),
+			array_keys( $result->getResultData( array( 'foo' ) ) ) );
+
+		$result->reset();
+		$result->addValue( null, 'sub', array( 'foo' => 1 ) );
+		$result->addValue( null, 'sub', array( 'bar' => 1 ) );
+		$this->assertSame( array( 'sub' => array( 'foo' => 1, 'bar' => 1 ) ),
+			$result->getResultData() );
+
+		try {
+			$result->addValue( null, 'sub', array( 'foo' => 2, 'baz' => 2 ) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( RuntimeException $ex ) {
+			$this->assertSame(
+				'Conflicting keys (foo) when attempting to merge element sub',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$result->reset();
+		$title = Title::newFromText( "MediaWiki:Foobar" );
+		$obj = new stdClass;
+		$obj->foo = 1;
+		$obj->bar = 2;
+		$result->addValue( null, 'title', $title );
+		$result->addValue( null, 'obj', $obj );
+		$this->assertSame( array(
+			'title' => (string)$title,
+			'obj' => array( 'foo' => 1, 'bar' => 2, ApiResult::META_TYPE => 'assoc' ),
+		), $result->getResultData() );
+
+		$fh = tmpfile();
+		try {
+			$result->addValue( null, 'file', $fh );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add resource(stream) to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		try {
+			$obj->file = $fh;
+			$result->addValue( null, 'sub', $obj );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add resource(stream) to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		fclose( $fh );
+
+		try {
+			$result->addValue( null, 'inf', INF );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add non-finite floats to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		try {
+			$result->addValue( null, 'nan', NAN );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Cannot add non-finite floats to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$result->reset();
+		$result->addParsedLimit( 'foo', 12 );
+		$this->assertSame( array( 'limits' => array( 'foo' => 12 ) ), $result->getResultData() );
+		$result->addParsedLimit( 'foo', 13 );
+		$this->assertSame( array( 'limits' => array( 'foo' => 13 ) ), $result->getResultData() );
+		$this->assertSame( null, $result->getResultData( array( 'foo', 'bar', 'baz' ) ) );
+		$this->assertSame( 13, $result->getResultData( array( 'limits', 'foo' ) ) );
+		try {
+			$result->getResultData( array( 'limits', 'foo', 'bar' ) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( InvalidArgumentException $ex ) {
+			$this->assertSame(
+				'Path limits.foo is not an array',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$result = new ApiResult( 10 );
+		$formatter = new ApiErrorFormatter( $result, Language::factory( 'en' ), 'none', false );
+		$result->setErrorFormatter( $formatter );
+		$this->assertFalse( $result->addValue( null, 'foo', '12345678901' ) );
+		$this->assertTrue( $result->addValue( null, 'foo', '12345678901', ApiResult::NO_SIZE_CHECK ) );
+		$this->assertSame( 0, $result->getSize() );
+		$result->reset();
+		$this->assertTrue( $result->addValue( null, 'foo', '1234567890' ) );
+		$this->assertFalse( $result->addValue( null, 'foo', '1' ) );
+		$result->removeValue( null, 'foo' );
+		$this->assertTrue( $result->addValue( null, 'foo', '1' ) );
+
+		$result = new ApiResult( 8388608 );
+		$result2 = new ApiResult( 8388608 );
+		$result2->addValue( null, 'foo', 'bar' );
+		$result->addValue( null, 'baz', $result2 );
+		$this->assertSame( array( 'baz' => array( 'foo' => 'bar' ) ), $result->getResultData() );
+
+		$result = new ApiResult( 8388608 );
+		$result->addValue( null, 'foo', "foo\x80bar" );
+		$result->addValue( null, 'bar', "a\xcc\x81" );
+		$result->addValue( null, 'baz', 74 );
+		$this->assertSame( array(
+			'foo' => "foo\xef\xbf\xbdbar",
+			'bar' => "\xc3\xa1",
+			'baz' => 74,
+		), $result->getResultData() );
+	}
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testMetadata() {
+		$arr = array( 'foo' => array( 'bar' => array() ) );
+		$result = new ApiResult( 8388608 );
+		$result->addValue( null, 'foo', array( 'bar' => array() ) );
+
+		$expect = array(
+			'foo' => array(
+				'bar' => array(
+					ApiResult::META_INDEXED_TAG_NAME => 'ritn',
+					ApiResult::META_TYPE => 'default',
+				),
+				ApiResult::META_INDEXED_TAG_NAME => 'ritn',
+				ApiResult::META_TYPE => 'default',
+			),
+			ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+			ApiResult::META_INDEXED_TAG_NAME => 'itn',
+			ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar' ),
+			ApiResult::META_TYPE => 'array',
+		);
+
+		ApiResult::setSubelementsList( $arr, 'foo' );
+		ApiResult::setSubelementsList( $arr, array( 'bar', 'baz' ) );
+		ApiResult::unsetSubelementsList( $arr, 'baz' );
+		ApiResult::setIndexedTagNameRecursive( $arr, 'ritn' );
+		ApiResult::setIndexedTagName( $arr, 'itn' );
+		ApiResult::setPreserveKeysList( $arr, 'foo' );
+		ApiResult::setPreserveKeysList( $arr, array( 'bar', 'baz' ) );
+		ApiResult::unsetPreserveKeysList( $arr, 'baz' );
+		ApiResult::setArrayTypeRecursive( $arr, 'default' );
+		ApiResult::setArrayType( $arr, 'array' );
+		$this->assertSame( $expect, $arr );
+
+		$result->addSubelementsList( null, 'foo' );
+		$result->addSubelementsList( null, array( 'bar', 'baz' ) );
+		$result->removeSubelementsList( null, 'baz' );
+		$result->addIndexedTagNameRecursive( null, 'ritn' );
+		$result->addIndexedTagName( null, 'itn' );
+		$result->addPreserveKeysList( null, 'foo' );
+		$result->addPreserveKeysList( null, array( 'bar', 'baz' ) );
+		$result->removePreserveKeysList( null, 'baz' );
+		$result->addArrayTypeRecursive( null, 'default' );
+		$result->addArrayType( null, 'array' );
+		$this->assertSame( $expect, $result->getResultData() );
+
+		$arr = array( 'foo' => array( 'bar' => array() ) );
+		$expect = array(
+			'foo' => array(
+				'bar' => array(
+					ApiResult::META_TYPE => 'kvp',
+					ApiResult::META_KVP_KEY_NAME => 'key',
+				),
+				ApiResult::META_TYPE => 'kvp',
+				ApiResult::META_KVP_KEY_NAME => 'key',
+			),
+			ApiResult::META_TYPE => 'BCkvp',
+			ApiResult::META_KVP_KEY_NAME => 'bc',
+		);
+		ApiResult::setArrayTypeRecursive( $arr, 'kvp', 'key' );
+		ApiResult::setArrayType( $arr, 'BCkvp', 'bc' );
+		$this->assertSame( $expect, $arr );
+	}
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testUtilityFunctions() {
+		$arr = array(
+			'foo' => array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			'foo2' => (object)array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+			ApiResult::META_INDEXED_TAG_NAME => 'itn',
+			ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+			ApiResult::META_TYPE => 'array',
+			'_dummy' => 'foobaz',
+			'_dummy2' => 'foobaz!',
+		);
+		$this->assertEquals( array(
+			'foo' => array(
+				'bar' => array(),
+				'bar2' => (object)array(),
+				'x' => 'ok',
+			),
+			'foo2' => (object)array(
+				'bar' => array(),
+				'bar2' => (object)array(),
+				'x' => 'ok',
+			),
+			'_dummy2' => 'foobaz!',
+		), ApiResult::stripMetadata( $arr ), 'ApiResult::stripMetadata' );
+
+		$metadata = array();
+		$data = ApiResult::stripMetadataNonRecursive( $arr, $metadata );
+		$this->assertEquals( array(
+			'foo' => array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			'foo2' => (object)array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			'_dummy2' => 'foobaz!',
+		), $data, 'ApiResult::stripMetadataNonRecursive ($data)' );
+		$this->assertEquals( array(
+			ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+			ApiResult::META_INDEXED_TAG_NAME => 'itn',
+			ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+			ApiResult::META_TYPE => 'array',
+			'_dummy' => 'foobaz',
+		), $metadata, 'ApiResult::stripMetadataNonRecursive ($metadata)' );
+
+		$metadata = null;
+		$data = ApiResult::stripMetadataNonRecursive( (object)$arr, $metadata );
+		$this->assertEquals( (object)array(
+			'foo' => array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			'foo2' => (object)array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'bar2' => (object)array( '_dummy' => 'foobaz' ),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			'_dummy2' => 'foobaz!',
+		), $data, 'ApiResult::stripMetadataNonRecursive on object ($data)' );
+		$this->assertEquals( array(
+			ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+			ApiResult::META_INDEXED_TAG_NAME => 'itn',
+			ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+			ApiResult::META_TYPE => 'array',
+			'_dummy' => 'foobaz',
+		), $metadata, 'ApiResult::stripMetadataNonRecursive on object ($metadata)' );
+	}
+
+	/**
+	 * @covers ApiResult
+	 * @dataProvider provideTransformations
+	 * @param string $label
+	 * @param array $input
+	 * @param array $transforms
+	 * @param array|Exception $expect
+	 */
+	public function testTransformations( $label, $input, $transforms, $expect ) {
+		$result = new ApiResult( false );
+		$result->addValue( null, 'test', $input );
+
+		if ( $expect instanceof Exception ) {
+			try {
+				$output = $result->getResultData( 'test', $transforms );
+				$this->fail( 'Expected exception not thrown', $label );
+			} catch ( Exception $ex ) {
+				$this->assertEquals( $ex, $expect, $label );
+			}
+		} else {
+			$output = $result->getResultData( 'test', $transforms );
+			$this->assertEquals( $expect, $output, $label );
+		}
+	}
+
+	public function provideTransformations() {
+		$kvp = function ( $keyKey, $key, $valKey, $value ) {
+			return array(
+				$keyKey => $key,
+				$valKey => $value,
+				ApiResult::META_PRESERVE_KEYS => array( $keyKey ),
+				ApiResult::META_CONTENT => $valKey,
+				ApiResult::META_TYPE => 'assoc',
+			);
+		};
+		$typeArr = array(
+			'defaultArray' => array( 2 => 'a', 0 => 'b', 1 => 'c' ),
+			'defaultAssoc' => array( 'x' => 'a', 1 => 'b', 0 => 'c' ),
+			'defaultAssoc2' => array( 2 => 'a', 3 => 'b', 0 => 'c' ),
+			'array' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'array' ),
+			'BCarray' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'BCarray' ),
+			'BCassoc' => array( 'a', 'b', 'c', ApiResult::META_TYPE => 'BCassoc' ),
+			'assoc' => array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+			'kvp' => array( 'x' => 'a', 'y' => 'b', 'z' => array( 'c' ), ApiResult::META_TYPE => 'kvp' ),
+			'BCkvp' => array( 'x' => 'a', 'y' => 'b',
+				ApiResult::META_TYPE => 'BCkvp',
+				ApiResult::META_KVP_KEY_NAME => 'key',
+			),
+			'emptyDefault' => array( '_dummy' => 1 ),
+			'emptyAssoc' => array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+			'_dummy' => 1,
+			ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+		);
+		$stripArr = array(
+			'foo' => array(
+				'bar' => array( '_dummy' => 'foobaz' ),
+				'baz' => array(
+					ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+					ApiResult::META_INDEXED_TAG_NAME => 'itn',
+					ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+					ApiResult::META_TYPE => 'array',
+				),
+				'x' => 'ok',
+				'_dummy' => 'foobaz',
+			),
+			ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+			ApiResult::META_INDEXED_TAG_NAME => 'itn',
+			ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+			ApiResult::META_TYPE => 'array',
+			'_dummy' => 'foobaz',
+			'_dummy2' => 'foobaz!',
+		);
+
+		return array(
+			array(
+				'BC: META_BC_BOOLS',
+				array(
+					'BCtrue' => true,
+					'BCfalse' => false,
+					'true' => true,
+					'false' => false,
+					ApiResult::META_BC_BOOLS => array( 0, 'true', 'false' ),
+				),
+				array( 'BC' => array() ),
+				array(
+					'BCtrue' => '',
+					'true' => true,
+					'false' => false,
+					ApiResult::META_BC_BOOLS => array( 0, 'true', 'false' ),
+				)
+			),
+			array(
+				'BC: META_BC_SUBELEMENTS',
+				array(
+					'bc' => 'foo',
+					'nobc' => 'bar',
+					ApiResult::META_BC_SUBELEMENTS => array( 'bc' ),
+				),
+				array( 'BC' => array() ),
+				array(
+					'bc' => array(
+						'*' => 'foo',
+						ApiResult::META_CONTENT => '*',
+						ApiResult::META_TYPE => 'assoc',
+					),
+					'nobc' => 'bar',
+					ApiResult::META_BC_SUBELEMENTS => array( 'bc' ),
+				),
+			),
+			array(
+				'BC: META_CONTENT',
+				array(
+					'content' => '!!!',
+					ApiResult::META_CONTENT => 'content',
+				),
+				array( 'BC' => array() ),
+				array(
+					'*' => '!!!',
+					ApiResult::META_CONTENT => '*',
+				),
+			),
+			array(
+				'BC: BCkvp type',
+				array(
+					'foo' => 'foo value',
+					'bar' => 'bar value',
+					'_baz' => 'baz value',
+					ApiResult::META_TYPE => 'BCkvp',
+					ApiResult::META_KVP_KEY_NAME => 'key',
+					ApiResult::META_PRESERVE_KEYS => array( '_baz' ),
+				),
+				array( 'BC' => array() ),
+				array(
+					$kvp( 'key', 'foo', '*', 'foo value' ),
+					$kvp( 'key', 'bar', '*', 'bar value' ),
+					$kvp( 'key', '_baz', '*', 'baz value' ),
+					ApiResult::META_TYPE => 'array',
+					ApiResult::META_KVP_KEY_NAME => 'key',
+					ApiResult::META_PRESERVE_KEYS => array( '_baz' ),
+				),
+			),
+			array(
+				'BC: BCarray type',
+				array(
+					ApiResult::META_TYPE => 'BCarray',
+				),
+				array( 'BC' => array() ),
+				array(
+					ApiResult::META_TYPE => 'default',
+				),
+			),
+			array(
+				'BC: BCassoc type',
+				array(
+					ApiResult::META_TYPE => 'BCassoc',
+				),
+				array( 'BC' => array() ),
+				array(
+					ApiResult::META_TYPE => 'default',
+				),
+			),
+			array(
+				'BC: BCkvp exception',
+				array(
+					ApiResult::META_TYPE => 'BCkvp',
+				),
+				array( 'BC' => array() ),
+				new UnexpectedValueException(
+					'Type "BCkvp" used without setting ApiResult::META_KVP_KEY_NAME metadata item'
+				),
+			),
+			array(
+				'BC: nobool, no*, nosub',
+				array(
+					'true' => true,
+					'false' => false,
+					'content' => 'content',
+					ApiResult::META_CONTENT => 'content',
+					'bc' => 'foo',
+					ApiResult::META_BC_SUBELEMENTS => array( 'bc' ),
+					'BCarray' => array( ApiResult::META_TYPE => 'BCarray' ),
+					'BCassoc' => array( ApiResult::META_TYPE => 'BCassoc' ),
+					'BCkvp' => array(
+						'foo' => 'foo value',
+						'bar' => 'bar value',
+						'_baz' => 'baz value',
+						ApiResult::META_TYPE => 'BCkvp',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+						ApiResult::META_PRESERVE_KEYS => array( '_baz' ),
+					),
+				),
+				array( 'BC' => array( 'nobool', 'no*', 'nosub' ) ),
+				array(
+					'true' => true,
+					'false' => false,
+					'content' => 'content',
+					'bc' => 'foo',
+					'BCarray' => array( ApiResult::META_TYPE => 'default' ),
+					'BCassoc' => array( ApiResult::META_TYPE => 'default' ),
+					'BCkvp' => array(
+						$kvp( 'key', 'foo', '*', 'foo value' ),
+						$kvp( 'key', 'bar', '*', 'bar value' ),
+						$kvp( 'key', '_baz', '*', 'baz value' ),
+						ApiResult::META_TYPE => 'array',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+						ApiResult::META_PRESERVE_KEYS => array( '_baz' ),
+					),
+					ApiResult::META_CONTENT => 'content',
+					ApiResult::META_BC_SUBELEMENTS => array( 'bc' ),
+				),
+			),
+
+			array(
+				'Types: Normal transform',
+				$typeArr,
+				array( 'Types' => array() ),
+				array(
+					'defaultArray' => array( 'b', 'c', 'a', ApiResult::META_TYPE => 'array' ),
+					'defaultAssoc' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'defaultAssoc2' => array( 2 => 'a', 3 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'array' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCarray' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCassoc' => array( 'a', 'b', 'c', ApiResult::META_TYPE => 'assoc' ),
+					'assoc' => array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'kvp' => array( 'x' => 'a', 'y' => 'b',
+						'z' => array( 'c', ApiResult::META_TYPE => 'array' ),
+						ApiResult::META_TYPE => 'assoc'
+					),
+					'BCkvp' => array( 'x' => 'a', 'y' => 'b',
+						ApiResult::META_TYPE => 'assoc',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+					),
+					'emptyDefault' => array( '_dummy' => 1, ApiResult::META_TYPE => 'array' ),
+					'emptyAssoc' => array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+					'_dummy' => 1,
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+					ApiResult::META_TYPE => 'assoc',
+				),
+			),
+			array(
+				'Types: AssocAsObject',
+				$typeArr,
+				array( 'Types' => array( 'AssocAsObject' => true ) ),
+				(object)array(
+					'defaultArray' => array( 'b', 'c', 'a', ApiResult::META_TYPE => 'array' ),
+					'defaultAssoc' => (object)array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'defaultAssoc2' => (object)array( 2 => 'a', 3 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'array' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCarray' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCassoc' => (object)array( 'a', 'b', 'c', ApiResult::META_TYPE => 'assoc' ),
+					'assoc' => (object)array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'kvp' => (object)array( 'x' => 'a', 'y' => 'b',
+						'z' => array( 'c', ApiResult::META_TYPE => 'array' ),
+						ApiResult::META_TYPE => 'assoc'
+					),
+					'BCkvp' => (object)array( 'x' => 'a', 'y' => 'b',
+						ApiResult::META_TYPE => 'assoc',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+					),
+					'emptyDefault' => array( '_dummy' => 1, ApiResult::META_TYPE => 'array' ),
+					'emptyAssoc' => (object)array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+					'_dummy' => 1,
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+					ApiResult::META_TYPE => 'assoc',
+				),
+			),
+			array(
+				'Types: ArmorKVP',
+				$typeArr,
+				array( 'Types' => array( 'ArmorKVP' => 'name' ) ),
+				array(
+					'defaultArray' => array( 'b', 'c', 'a', ApiResult::META_TYPE => 'array' ),
+					'defaultAssoc' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'defaultAssoc2' => array( 2 => 'a', 3 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'array' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCarray' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCassoc' => array( 'a', 'b', 'c', ApiResult::META_TYPE => 'assoc' ),
+					'assoc' => array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'kvp' => array(
+						$kvp( 'name', 'x', 'value', 'a' ),
+						$kvp( 'name', 'y', 'value', 'b' ),
+						$kvp( 'name', 'z', 'value', array( 'c', ApiResult::META_TYPE => 'array' ) ),
+						ApiResult::META_TYPE => 'array'
+					),
+					'BCkvp' => array(
+						$kvp( 'key', 'x', 'value', 'a' ),
+						$kvp( 'key', 'y', 'value', 'b' ),
+						ApiResult::META_TYPE => 'array',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+					),
+					'emptyDefault' => array( '_dummy' => 1, ApiResult::META_TYPE => 'array' ),
+					'emptyAssoc' => array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+					'_dummy' => 1,
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+					ApiResult::META_TYPE => 'assoc',
+				),
+			),
+			array(
+				'Types: ArmorKVP + BC',
+				$typeArr,
+				array( 'BC' => array(), 'Types' => array( 'ArmorKVP' => 'name' ) ),
+				array(
+					'defaultArray' => array( 'b', 'c', 'a', ApiResult::META_TYPE => 'array' ),
+					'defaultAssoc' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'defaultAssoc2' => array( 2 => 'a', 3 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'array' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCarray' => array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'BCassoc' => array( 'a', 'b', 'c', ApiResult::META_TYPE => 'array' ),
+					'assoc' => array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'kvp' => array(
+						$kvp( 'name', 'x', '*', 'a' ),
+						$kvp( 'name', 'y', '*', 'b' ),
+						$kvp( 'name', 'z', '*', array( 'c', ApiResult::META_TYPE => 'array' ) ),
+						ApiResult::META_TYPE => 'array'
+					),
+					'BCkvp' => array(
+						$kvp( 'key', 'x', '*', 'a' ),
+						$kvp( 'key', 'y', '*', 'b' ),
+						ApiResult::META_TYPE => 'array',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+					),
+					'emptyDefault' => array( '_dummy' => 1, ApiResult::META_TYPE => 'array' ),
+					'emptyAssoc' => array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+					'_dummy' => 1,
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+					ApiResult::META_TYPE => 'assoc',
+				),
+			),
+			array(
+				'Types: ArmorKVP + AssocAsObject',
+				$typeArr,
+				array( 'Types' => array( 'ArmorKVP' => 'name', 'AssocAsObject' => true ) ),
+				(object)array(
+					'defaultArray' => array( 'b', 'c', 'a', ApiResult::META_TYPE => 'array' ),
+					'defaultAssoc' => (object)array( 'x' => 'a', 1 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'defaultAssoc2' => (object)array( 2 => 'a', 3 => 'b', 0 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'array' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCarray' => array( 'a', 'c', 'b', ApiResult::META_TYPE => 'array' ),
+					'BCassoc' => (object)array( 'a', 'b', 'c', ApiResult::META_TYPE => 'assoc' ),
+					'assoc' => (object)array( 2 => 'a', 0 => 'b', 1 => 'c', ApiResult::META_TYPE => 'assoc' ),
+					'kvp' => array(
+						(object)$kvp( 'name', 'x', 'value', 'a' ),
+						(object)$kvp( 'name', 'y', 'value', 'b' ),
+						(object)$kvp( 'name', 'z', 'value', array( 'c', ApiResult::META_TYPE => 'array' ) ),
+						ApiResult::META_TYPE => 'array'
+					),
+					'BCkvp' => array(
+						(object)$kvp( 'key', 'x', 'value', 'a' ),
+						(object)$kvp( 'key', 'y', 'value', 'b' ),
+						ApiResult::META_TYPE => 'array',
+						ApiResult::META_KVP_KEY_NAME => 'key',
+					),
+					'emptyDefault' => array( '_dummy' => 1, ApiResult::META_TYPE => 'array' ),
+					'emptyAssoc' => (object)array( '_dummy' => 1, ApiResult::META_TYPE => 'assoc' ),
+					'_dummy' => 1,
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy' ),
+					ApiResult::META_TYPE => 'assoc',
+				),
+			),
+			array(
+				'Types: BCkvp exception',
+				array(
+					ApiResult::META_TYPE => 'BCkvp',
+				),
+				array( 'Types' => array() ),
+				new UnexpectedValueException(
+					'Type "BCkvp" used without setting ApiResult::META_KVP_KEY_NAME metadata item'
+				),
+			),
+
+			array(
+				'Strip: With ArmorKVP + AssocAsObject transforms',
+				$typeArr,
+				array( 'Types' => array( 'ArmorKVP' => 'name', 'AssocAsObject' => true ), 'Strip' => 'all' ),
+				(object)array(
+					'defaultArray' => array( 'b', 'c', 'a' ),
+					'defaultAssoc' => (object)array( 'x' => 'a', 1 => 'b', 0 => 'c' ),
+					'defaultAssoc2' => (object)array( 2 => 'a', 3 => 'b', 0 => 'c' ),
+					'array' => array( 'a', 'c', 'b' ),
+					'BCarray' => array( 'a', 'c', 'b' ),
+					'BCassoc' => (object)array( 'a', 'b', 'c' ),
+					'assoc' => (object)array( 2 => 'a', 0 => 'b', 1 => 'c' ),
+					'kvp' => array(
+						(object)array( 'name' => 'x', 'value' => 'a' ),
+						(object)array( 'name' => 'y', 'value' => 'b' ),
+						(object)array( 'name' => 'z', 'value' => array( 'c' ) ),
+					),
+					'BCkvp' => array(
+						(object)array( 'key' => 'x', 'value' => 'a' ),
+						(object)array( 'key' => 'y', 'value' => 'b' ),
+					),
+					'emptyDefault' => array(),
+					'emptyAssoc' => (object)array(),
+					'_dummy' => 1,
+				),
+			),
+
+			array(
+				'Strip: all',
+				$stripArr,
+				array( 'Strip' => 'all' ),
+				array(
+					'foo' => array(
+						'bar' => array(),
+						'baz' => array(),
+						'x' => 'ok',
+					),
+					'_dummy2' => 'foobaz!',
+				),
+			),
+			array(
+				'Strip: base',
+				$stripArr,
+				array( 'Strip' => 'base' ),
+				array(
+					'foo' => array(
+						'bar' => array( '_dummy' => 'foobaz' ),
+						'baz' => array(
+							ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+							ApiResult::META_INDEXED_TAG_NAME => 'itn',
+							ApiResult::META_PRESERVE_KEYS => array( 'foo', 'bar', '_dummy2', 0 ),
+							ApiResult::META_TYPE => 'array',
+						),
+						'x' => 'ok',
+						'_dummy' => 'foobaz',
+					),
+					'_dummy2' => 'foobaz!',
+				),
+			),
+			array(
+				'Strip: bc',
+				$stripArr,
+				array( 'Strip' => 'bc' ),
+				array(
+					'foo' => array(
+						'bar' => array(),
+						'baz' => array(
+							ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+							ApiResult::META_INDEXED_TAG_NAME => 'itn',
+						),
+						'x' => 'ok',
+					),
+					'_dummy2' => 'foobaz!',
+					ApiResult::META_SUBELEMENTS => array( 'foo', 'bar' ),
+					ApiResult::META_INDEXED_TAG_NAME => 'itn',
+				),
+			),
+
+			array(
+				'Custom transform',
+				array(
+					'foo' => '?',
+					'bar' => '?',
+					'_dummy' => '?',
+					'_dummy2' => '?',
+					'_dummy3' => '?',
+					ApiResult::META_CONTENT => 'foo',
+					ApiResult::META_PRESERVE_KEYS => array( '_dummy2', '_dummy3' ),
+				),
+				array(
+					'Custom' => array( $this, 'customTransform' ),
+					'BC' => array(),
+					'Types' => array(),
+					'Strip' => 'all'
+				),
+				array(
+					'*' => 'FOO',
+					'bar' => 'BAR',
+					'baz' => array( 'a', 'b' ),
+					'_dummy2' => '_DUMMY2',
+					'_dummy3' => '_DUMMY3',
+					ApiResult::META_CONTENT => 'bar',
+				),
+			),
+		);
+
+	}
+
+	/**
+	 * Custom transformer for testTransformations
+	 * @param array &$data
+	 * @param array &$metadata
+	 */
+	public function customTransform( &$data, &$metadata ) {
+		// Prevent recursion
+		if ( isset( $metadata['_added'] ) ) {
+			$metadata[ApiResult::META_TYPE] = 'array';
+			return;
+		}
+
+		foreach ( $data as $k => $v ) {
+			$data[$k] = strtoupper( $k );
+		}
+		$data['baz'] = array( '_added' => 1, 'z' => 'b', 'y' => 'a' );
+		$metadata[ApiResult::META_PRESERVE_KEYS][0] = '_dummy';
+		$data[ApiResult::META_CONTENT] = 'bar';
+	}
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testDeprecatedFunctions() {
+		// Ignore ApiResult deprecation warnings during this test
+		set_error_handler( function ( $errno, $errstr ) use ( &$warnings ) {
+			if ( preg_match( '/Use of ApiResult::\S+ was deprecated in MediaWiki \d+.\d+\./', $errstr ) ) {
+				return true;
+			}
+			return false;
+		} );
+		$reset = new ScopedCallback( 'restore_error_handler' );
+
+		$context = new DerivativeContext( RequestContext::getMain() );
+		$context->setConfig( new HashConfig( array(
+			'APIModules' => array(),
+			'APIFormatModules' => array(),
+			'APIMaxResultSize' => 42,
+		) ) );
+		$main = new ApiMain( $context );
+		$result = TestingAccessWrapper::newFromObject( new ApiResult( $main ) );
+		$this->assertSame( 42, $result->maxSize );
+		$this->assertSame( $main->getErrorFormatter(), $result->errorFormatter );
+		$this->assertSame( $main, $result->mainForContinuation );
+
+		$result = new ApiResult( 8388608 );
+
+		$result->addContentValue( null, 'test', 'content' );
+		$result->addContentValue( array( 'foo', 'bar' ), 'test', 'content' );
+		$result->addIndexedTagName( null, 'itn' );
+		$result->addSubelementsList( null, array( 'sub' ) );
+		$this->assertSame( array(
+			'foo' => array(
+				'bar' => array(
+					'*' => 'content',
+				),
+			),
+			'*' => 'content',
+		), $result->getData() );
+		$result->setRawMode();
+		$this->assertSame( array(
+			'foo' => array(
+				'bar' => array(
+					'*' => 'content',
+				),
+			),
+			'*' => 'content',
+			'_element' => 'itn',
+			'_subelements' => array( 'sub' ),
+		), $result->getData() );
+
+		$arr = array();
+		ApiResult::setContent( $arr, 'value' );
+		ApiResult::setContent( $arr, 'value2', 'foobar' );
+		$this->assertSame( array(
+			ApiResult::META_CONTENT => 'content',
+			'content' => 'value',
+			'foobar' => array(
+				ApiResult::META_CONTENT => 'content',
+				'content' => 'value2',
+			),
+		), $arr );
+
+		$result = new ApiResult( 3 );
+		$formatter = new ApiErrorFormatter_BackCompat( $result );
+		$result->setErrorFormatter( $formatter );
+		$result->disableSizeCheck();
+		$this->assertTrue( $result->addValue( null, 'foo', '1234567890' ) );
+		$result->enableSizeCheck();
+		$this->assertSame( 0, $result->getSize() );
+		$this->assertFalse( $result->addValue( null, 'foo', '1234567890' ) );
+
+		$arr = array( 'foo' => array( 'bar' => 1 ) );
+		$result->setIndexedTagName_recursive( $arr, 'itn' );
+		$this->assertSame( array(
+			'foo' => array(
+				'bar' => 1,
+				ApiResult::META_INDEXED_TAG_NAME => 'itn'
+			),
+		), $arr );
+
+		$status = Status::newGood();
+		$status->fatal( 'parentheses', '1' );
+		$status->fatal( 'parentheses', '2' );
+		$status->warning( 'parentheses', '3' );
+		$status->warning( 'parentheses', '4' );
+		$this->assertSame( array(
+			array(
+				'type' => 'error',
+				'message' => 'parentheses',
+				'params' => array(
+					0 => '1',
+					ApiResult::META_INDEXED_TAG_NAME => 'param',
+				),
+			),
+			array(
+				'type' => 'error',
+				'message' => 'parentheses',
+				'params' => array(
+					0 => '2',
+					ApiResult::META_INDEXED_TAG_NAME => 'param',
+				),
+			),
+			ApiResult::META_INDEXED_TAG_NAME => 'error',
+		), $result->convertStatusToArray( $status, 'error' ) );
+		$this->assertSame( array(
+			array(
+				'type' => 'warning',
+				'message' => 'parentheses',
+				'params' => array(
+					0 => '3',
+					ApiResult::META_INDEXED_TAG_NAME => 'param',
+				),
+			),
+			array(
+				'type' => 'warning',
+				'message' => 'parentheses',
+				'params' => array(
+					0 => '4',
+					ApiResult::META_INDEXED_TAG_NAME => 'param',
+				),
+			),
+			ApiResult::META_INDEXED_TAG_NAME => 'warning',
+		), $result->convertStatusToArray( $status, 'warning' ) );
+	}
+
+	/**
+	 * @covers ApiResult
+	 */
+	public function testDeprecatedContinuation() {
+		// Ignore ApiResult deprecation warnings during this test
+		set_error_handler( function ( $errno, $errstr ) use ( &$warnings ) {
+			if ( preg_match( '/Use of ApiResult::\S+ was deprecated in MediaWiki \d+.\d+\./', $errstr ) ) {
+				return true;
+			}
+			return false;
+		} );
+
+		$reset = new ScopedCallback( 'restore_error_handler' );
+		$allModules = array(
+			new MockApiQueryBase( 'mock1' ),
+			new MockApiQueryBase( 'mock2' ),
+			new MockApiQueryBase( 'mocklist' ),
+		);
+		$generator = new MockApiQueryBase( 'generator' );
+
+		$main = new ApiMain( RequestContext::getMain() );
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[0], 'm1continue', array( 1, 2 ) );
+		$result->setContinueParam( $allModules[2], 'mlcontinue', 2 );
+		$result->setGeneratorContinueParam( $generator, 'gcontinue', 3 );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'mlcontinue' => 2,
+			'm1continue' => '1|2',
+			'continue' => '||mock2',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( null, $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mock1' => array( 'm1continue' => '1|2' ),
+			'mocklist' => array( 'mlcontinue' => 2 ),
+			'generator' => array( 'gcontinue' => 3 ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[0], 'm1continue', array( 1, 2 ) );
+		$result->setGeneratorContinueParam( $generator, 'gcontinue', array( 3, 4 ) );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'm1continue' => '1|2',
+			'continue' => '||mock2|mocklist',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( null, $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mock1' => array( 'm1continue' => '1|2' ),
+			'generator' => array( 'gcontinue' => '3|4' ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[2], 'mlcontinue', 2 );
+		$result->setGeneratorContinueParam( $generator, 'gcontinue', 3 );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'mlcontinue' => 2,
+			'gcontinue' => 3,
+			'continue' => 'gcontinue||',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( '', $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mocklist' => array( 'mlcontinue' => 2 ),
+			'generator' => array( 'gcontinue' => 3 ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setGeneratorContinueParam( $generator, 'gcontinue', 3 );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'gcontinue' => 3,
+			'continue' => 'gcontinue||mocklist',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( '', $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'generator' => array( 'gcontinue' => 3 ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[0], 'm1continue', array( 1, 2 ) );
+		$result->setContinueParam( $allModules[2], 'mlcontinue', 2 );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'mlcontinue' => 2,
+			'm1continue' => '1|2',
+			'continue' => '||mock2',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( null, $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mock1' => array( 'm1continue' => '1|2' ),
+			'mocklist' => array( 'mlcontinue' => 2 ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[0], 'm1continue', array( 1, 2 ) );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'm1continue' => '1|2',
+			'continue' => '||mock2|mocklist',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( null, $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mock1' => array( 'm1continue' => '1|2' ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->setContinueParam( $allModules[2], 'mlcontinue', 2 );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( array(
+			'mlcontinue' => 2,
+			'continue' => '-||mock1|mock2',
+		), $result->getResultData( 'continue' ) );
+		$this->assertSame( '', $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( array(
+			'mocklist' => array( 'mlcontinue' => 2 ),
+		), $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( null, $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame( array( false, $allModules ), $ret );
+		$result->endContinuation( 'raw' );
+		$result->endContinuation( 'standard' );
+		$this->assertSame( null, $result->getResultData( 'continue' ) );
+		$this->assertSame( '', $result->getResultData( 'batchcomplete' ) );
+		$this->assertSame( null, $result->getResultData( 'query-continue' ) );
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( '||mock2', $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame(
+			array( false, array_values( array_diff_key( $allModules, array( 1 => 1 ) ) ) ),
+			$ret
+		);
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$ret = $result->beginContinuation( '-||', $allModules, array( 'mock1', 'mock2' ) );
+		$this->assertSame(
+			array( true, array_values( array_diff_key( $allModules, array( 0 => 0, 1 => 1 ) ) ) ),
+			$ret
+		);
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		try {
+			$result->beginContinuation( 'foo', $allModules, array( 'mock1', 'mock2' ) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( UsageException $ex ) {
+			$this->assertSame(
+				'Invalid continue param. You should pass the original value returned by the previous query',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		$main->setContinuationManager( null );
+
+		$result = new ApiResult( 8388608 );
+		$result->setMainForContinuation( $main );
+		$result->beginContinuation( '||mock2', array_slice( $allModules, 0, 2 ), array( 'mock1', 'mock2' ) );
+		try {
+			$result->setContinueParam( $allModules[1], 'm2continue', 1 );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( UnexpectedValueException $ex ) {
+			$this->assertSame(
+				'Module \'mock2\' was not supposed to have been executed, but it was executed anyway',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		try {
+			$result->setContinueParam( $allModules[2], 'mlcontinue', 1 );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( UnexpectedValueException $ex ) {
+			$this->assertSame(
+				'Module \'mocklist\' called ApiContinuationManager::addContinueParam but was not passed to ApiContinuationManager::__construct',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+		$main->setContinuationManager( null );
+
+	}
+
+	public function testObjectSerialization() {
+		$arr = array();
+		ApiResult::setValue( $arr, 'foo', (object)array( 'a' => 1, 'b' => 2 ) );
+		$this->assertSame( array(
+			'a' => 1,
+			'b' => 2,
+			ApiResult::META_TYPE => 'assoc',
+		), $arr['foo'] );
+
+		$arr = array();
+		ApiResult::setValue( $arr, 'foo', new ApiResultTestStringifiableObject() );
+		$this->assertSame( 'Ok', $arr['foo'] );
+
+		$arr = array();
+		ApiResult::setValue( $arr, 'foo', new ApiResultTestSerializableObject( 'Ok' ) );
+		$this->assertSame( 'Ok', $arr['foo'] );
+
+		try {
+			$arr = array();
+			ApiResult::setValue( $arr, 'foo',  new ApiResultTestSerializableObject(
+				new ApiResultTestStringifiableObject()
+			) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( UnexpectedValueException $ex ) {
+			$this->assertSame(
+				'ApiResultTestSerializableObject::serializeForApiResult() returned an object of class ApiResultTestStringifiableObject',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		try {
+			$arr = array();
+			ApiResult::setValue( $arr, 'foo',  new ApiResultTestSerializableObject( NAN ) );
+			$this->fail( 'Expected exception not thrown' );
+		} catch ( UnexpectedValueException $ex ) {
+			$this->assertSame(
+				'ApiResultTestSerializableObject::serializeForApiResult() returned an invalid value: Cannot add non-finite floats to ApiResult',
+				$ex->getMessage(),
+				'Expected exception'
+			);
+		}
+
+		$arr = array();
+		ApiResult::setValue( $arr, 'foo',  new ApiResultTestSerializableObject(
+			array(
+				'one' => new ApiResultTestStringifiableObject( '1' ),
+				'two' => new ApiResultTestSerializableObject( 2 ),
+			)
+		) );
+		$this->assertSame( array(
+			'one' => '1',
+			'two' => 2,
+		), $arr['foo'] );
+	}
+
+}
+
+class ApiResultTestStringifiableObject {
+	private $ret;
+
+	public function __construct( $ret = 'Ok' ) {
+		$this->ret = $ret;
+	}
+
+	public function __toString() {
+		return $this->ret;
+	}
+}
+
+class ApiResultTestSerializableObject {
+	private $ret;
+
+	public function __construct( $ret ) {
+		$this->ret = $ret;
+	}
+
+	public function __toString() {
+		return "Fail";
+	}
+
+	public function serializeForApiResult() {
+		return $this->ret;
+	}
+}