Check if media wiki core is capable of xml type checking

* new test for XML type checking function
* check if StrigUtils::isUtf8 exists in core (Thanks to Deyan Ginev for the hint.)

Bug: 50884
Change-Id: I86af95cbecc4b5c9c33fcd3a66a7fb2ccdde0194

Math.i18n.php

@@ -39,6 +39,7 @@ $messages['en'] = array(
 	'math_latexml_invalidresponse' => 'LaTeXML Invalid response (\'$2\') from server \'$1\':',
 	'math_latexml_invalidxml' => 'LaTeXML MathML is invalid XML.',
 	'math_latexml_invalidjson'  => 'LaTeXML Server response is invalid JSON.',
+	'math_latexml_xmlversion' => 'Warning: XML Type check skipped! Check if your MediaWiki installation is version wmf/1.22wmf7 or newer.'
 );
 
 /** Message documentation (Message documentation)
@@ -145,6 +146,8 @@ This message follows the message {{msg-mw|Math failure}}.',
 	'math_latexml_invalidjson' => 'Used as error message.
 
 This message follows the message {{msg-mw|Math failure}}.',
+
+	'math_latexml_xmlversion' => 'Warning that XML checking of MathML requires wmf/1.22wmf7 or newer.'
 );
 
 /** Achinese (Acèh)

MathLaTeXML.php

@@ -156,7 +156,7 @@ class MathLaTeXML extends MathRenderer {
 	 * and the input string only.
 	 * @return string HTTP POST data
 	 */
-	public function getPostData(){
+	public function getPostData() {
 		$texcmd = urlencode( $this->tex );
 		return $this->getLaTeXMLSettings() . '&tex=' . $texcmd;
 	}
@@ -204,13 +204,19 @@ class MathLaTeXML extends MathRenderer {
 	 */
 	static public function isValidMathML( $XML ) {
 		$out = false;
-		//depends on https://gerrit.wikimedia.org/r/#/c/66365/
-		$xmlObject = new XmlTypeCheck($XML, null, false);
+		// depends on https://gerrit.wikimedia.org/r/#/c/66365/
+		if ( ! is_callable( 'XmlTypeCheck::newFromString' ) ) {
+			$msg = wfMessage( 'math_latexml_xmlversion' )->inContentLanguage()->escaped();
+			trigger_error( $msg, E_USER_NOTICE );
+			wfDebugLog( 'Math', $msg );
+			return true;
+		}
+		$xmlObject = new XmlTypeCheck( $XML, null, false );
 		if ( ! $xmlObject->wellFormed ) {
 			wfDebugLog( "Math", "XML validation error:\n " . var_export( $XML, true ) . "\n" );
 		} else {
 			$name = $xmlObject->getRootElement();
-			$name = str_replace('http://www.w3.org/1998/Math/MathML:', '', $name);
+			$name = str_replace( 'http://www.w3.org/1998/Math/MathML:', '', $name );
 			if ( $name == "math" or $name == "table" or $name == "div" ) {
 				$out = true;
 			} else {

MathRenderer.php

@@ -161,7 +161,14 @@ abstract class MathRenderer {
 			$this->conservativeness = $rpage->math_html_conservativeness;
 			$this->html = $rpage->math_html;
 			$this->mathml = utf8_decode( $rpage->math_mathml);
-			if ( StringUtils::isUtf8( $this->mathml ) ) {
+			if ( ! is_callable( 'StringUtils::isUtf8' ) ) {
+				$msg = wfMessage( 'math_latexml_xmlversion' )->inContentLanguage()->escaped();
+				trigger_error( $msg, E_USER_NOTICE );
+				wfDebugLog( 'Math', $msg );
+				//If we can not check if mathml output is valid, we skip the test and assume that it is valid.
+				$this->recall = true;
+				return true;
+			} elseif( StringUtils::isUtf8( $this->mathml ) ) {
 				$this->recall = true;
 				return true;
 			}

README

@@ -16,6 +16,9 @@ $wgDefaultUserOptions['math'] = MW_MATH_LATEXML;
 in the LocalSettings.php file.
 The LaTeXML option requires php5-curl to be installed. Without php5-curl no proper
 error handling can be guaranteed.
+Furthermore, a core version of wmf/1.22wmf7 or newer is recommended.
+Otherwise, errors in LaTeXML can lead to mal-formatted XML output and disturb the
+page layout.
 
 MathJax configuration:
 Client-side configuration of MathJax can be done by specifying a mathJax.config

tests/MathLaTeXMLTest.php

@@ -44,7 +44,7 @@ class MathLaTeXMLTest extends MediaWikiTestCase {
 			, "requestReturn is false if HTTP::post returns false." );
 		$this->assertEquals( false, $res
 			, "res is false if HTTP:post returns false." );
-		$errmsg = wfMessage( 'math_latexml_invalidresponse' , $url,'' )
+		$errmsg = wfMessage( 'math_latexml_invalidresponse' , $url, '' )
 			->inContentLanguage()->escaped();
 		$this->assertContains( $errmsg, $error
 			, "return an error if HTTP::post returns false" );
@@ -66,13 +66,13 @@ class MathLaTeXMLTest extends MediaWikiTestCase {
 			, 'LaTeXMLHttpRequestTester' );
 		$this->assertEquals( true, $requestReturn, "successful call return" );
 		$this->isTrue( $res, "successfull call" );
-		$this->assertEquals( $error,'', "successfull call errormessage" );
+		$this->assertEquals( $error, '', "successfull call errormessage" );
 	}
 
 	/**
 	 * Tests behavior of makeRequest() that communicates with the host.
 	 * Testcase: Timeout.
-	 * @covers MathTexvc::makeRequest
+	 * @covers MathLaTeXML::makeRequest
 	 */
 	public function testMakeRequestTimeout() {
 		self::setMockValues( false, true, true );
@@ -90,6 +90,17 @@ class MathLaTeXMLTest extends MediaWikiTestCase {
 		$this->assertContains( $errmsg, $error, "timeout call errormessage" );
 	}
 
+	/**
+	 * Checks if a String is a valid MathML element
+	 * @covers MathLaTeXML::isValidXML
+	 */
+	public function testisValidXML() {
+		$validSample = '<math>content</math>';
+		$invalidSample = '<notmath />';
+		$this->assertTrue( MathLaTeXML::isValidMathML( $validSample ), 'test if math expression is valid mathml sample' );
+		$this->assertFalse( MathLaTeXML::isValidMathML( $invalidSample ), 'test if math expression is invalid mathml sample' );
+
+	}
 	/**
 	 * Checks the basic functionallity
 	 * i.e. if the span element is generated right.