upload: Modernize callback code to make use of PHP7 syntax

* Update the two "processing_instruction_handler" and
  "external_dtd_handler" callbacks to use a syntax for the callback
  that doesn't stuff the class name in a string, but actually
  references the class.
* We don't need call_user_func() in modern PHP7 any more.
* Add and update a few type hints in UploadBase to make the code
  easier explorable.

Change-Id: I0ab3cfbe4f0bf15b1da4ab10fd9ffc1986d968d0

3 files changed, 14 insertions, 19 deletions

diff --git a/includes/libs/mime/XmlTypeCheck.php b/includes/libs/mime/XmlTypeCheck.php
index 3bd7a563fb55..2e0f0c8fd3c6 100644
--- a/includes/libs/mime/XmlTypeCheck.php
+++ b/includes/libs/mime/XmlTypeCheck.php
@@ -325,12 +325,7 @@ class XmlTypeCheck {
 		$callbackReturn = false;
 
 		if ( is_callable( $this->filterCallback ) ) {
-			$callbackReturn = call_user_func(
-				$this->filterCallback,
-				$name,
-				$attribs,
-				$data
-			);
+			$callbackReturn = ( $this->filterCallback )( $name, $attribs, $data );
 		}
 		if ( $callbackReturn ) {
 			// Filter hit!
@@ -354,8 +349,8 @@ class XmlTypeCheck {
 	private function processingInstructionHandler( $target, $data ) {
 		$callbackReturn = false;
 		if ( $this->parserOptions['processing_instruction_handler'] ) {
-			$callbackReturn = call_user_func(
-				$this->parserOptions['processing_instruction_handler'],
+			// @phan-suppress-next-line PhanTypeInvalidCallable false positive
+			$callbackReturn = $this->parserOptions['processing_instruction_handler'](
 				$target,
 				$data
 			);
@@ -383,7 +378,7 @@ class XmlTypeCheck {
 		$callbackReturn = false;
 
 		if ( $generalCallback ) {
-			$callbackReturn = call_user_func( $generalCallback, $dtd );
+			$callbackReturn = $generalCallback( $dtd );
 		}
 		if ( $callbackReturn ) {
 			// Filter hit!
@@ -394,8 +389,7 @@ class XmlTypeCheck {
 
 		$parsedDTD = $this->parseDTD( $dtd );
 		if ( $externalCallback && isset( $parsedDTD['type'] ) ) {
-			$callbackReturn = call_user_func(
-				$externalCallback,
+			$callbackReturn = $externalCallback(
 				$parsedDTD['type'],
 				$parsedDTD['publicid'] ?? null,
 				$parsedDTD['systemid'] ?? null
diff --git a/includes/upload/UploadBase.php b/includes/upload/UploadBase.php
index d39a6310ed1a..653b97c78127 100644
--- a/includes/upload/UploadBase.php
+++ b/includes/upload/UploadBase.php
@@ -175,7 +175,7 @@ abstract class UploadBase {
 	 *
 	 * @param WebRequest &$request
 	 * @param string|null $type
-	 * @return null|UploadBase
+	 * @return null|self
 	 */
 	public static function createFromRequest( &$request, $type = null ) {
 		$type = $type ?: $request->getVal( 'wpSourceType', 'File' );
@@ -188,6 +188,7 @@ abstract class UploadBase {
 		$type = ucfirst( $type );
 
 		// Give hooks the chance to handle this request
+		/** @var self|null $className */
 		$className = null;
 		Hooks::run( 'UploadCreateFromRequest', [ $type, &$className ] );
 		if ( $className === null ) {
@@ -199,16 +200,16 @@ abstract class UploadBase {
 		}
 
 		// Check whether this upload class is enabled
-		if ( !call_user_func( [ $className, 'isEnabled' ] ) ) {
+		if ( !$className::isEnabled() ) {
 			return null;
 		}
 
 		// Check whether the request is valid
-		if ( !call_user_func( [ $className, 'isValidRequest' ], $request ) ) {
+		if ( !$className::isValidRequest( $request ) ) {
 			return null;
 		}
 
-		/** @var UploadBase $handler */
+		/** @var self $handler */
 		$handler = new $className;
 
 		$handler->initializeFromRequest( $request );
@@ -1483,8 +1484,8 @@ abstract class UploadBase {
 			[ $this, 'checkSvgScriptCallback' ],
 			true,
 			[
-				'processing_instruction_handler' => 'UploadBase::checkSvgPICallback',
-				'external_dtd_handler' => 'UploadBase::checkSvgExternalDTD',
+				'processing_instruction_handler' => [ __CLASS__, 'checkSvgPICallback' ],
+				'external_dtd_handler' => [ __CLASS__, 'checkSvgExternalDTD' ],
 			]
 		);
 		if ( $check->wellFormed !== true ) {
diff --git a/tests/phpunit/includes/upload/UploadBaseTest.php b/tests/phpunit/includes/upload/UploadBaseTest.php
index bcc6452c4aeb..0bfdd41ac9a7 100644
--- a/tests/phpunit/includes/upload/UploadBaseTest.php
+++ b/tests/phpunit/includes/upload/UploadBaseTest.php
@@ -647,8 +647,8 @@ class UploadTestHandler extends UploadBase {
 			[ $this, 'checkSvgScriptCallback' ],
 			false,
 			[
-				'processing_instruction_handler' => 'UploadBase::checkSvgPICallback',
-				'external_dtd_handler' => 'UploadBase::checkSvgExternalDTD'
+				'processing_instruction_handler' => [ UploadBase::class, 'checkSvgPICallback' ],
+				'external_dtd_handler' => [ UploadBase::class, 'checkSvgExternalDTD' ],
 			]
 		);
 		return [ $check->wellFormed, $check->filterMatch ];