MathML Writer : Write Semantics (#20)

Author: Progi1984

docs/changes/0.3.0.md

@@ -3,6 +3,7 @@
 ## Enhancements
 
 - Added support for PHP 8.4 by [@Progi1984](https://github/Progi1984) in [#18](https://github.com/PHPOffice/Math/pull/18)
+- MathML Writer : Write Semantics by [@codinglist](https://github/codinglist) & [@Progi1984](https://github/Progi1984) in [#19](https://github.com/PHPOffice/Math/pull/19) & [#20](https://github.com/PHPOffice/Math/pull/20)
 
 ## Bug fixes
 

docs/index.md

@@ -48,7 +48,7 @@ Math is an open source project licensed under the terms of [MIT](https://github.
 | **Simple**                | Fraction             | :material-check: | :material-check: |
 |                           | Superscript          | :material-check: |                  |
 | **Architectural**         | Row                  | :material-check: | :material-check: |
-|                           | Semantics            |                  |                  |
+|                           | Semantics            | :material-check: |                  |
 
 ## Contributing
 

src/Math/Writer/MathML.php

@@ -40,6 +40,26 @@ protected function writeElementItem(Element\AbstractElement $element): void
     {
         $tagName = $this->getElementTagName($element);
 
+        // Element\AbstractGroupElement
+        if ($element instanceof Element\Semantics) {
+            $this->output->startElement($tagName);
+            // Write elements
+            foreach ($element->getElements() as $childElement) {
+                $this->writeElementItem($childElement);
+            }
+
+            // Write annotations
+            foreach ($element->getAnnotations() as $encoding => $annotation) {
+                $this->output->startElement('annotation');
+                $this->output->writeAttribute('encoding', $encoding);
+                $this->output->text($annotation);
+                $this->output->endElement();
+            }
+            $this->output->endElement();
+
+            return;
+        }
+
         // Element\AbstractGroupElement
         if ($element instanceof Element\AbstractGroupElement) {
             $this->output->startElement($tagName);
@@ -121,6 +141,9 @@ protected function getElementTagName(Element\AbstractElement $element): string
         if ($element instanceof Element\Operator) {
             return 'mo';
         }
+        if ($element instanceof Element\Semantics) {
+            return 'semantics';
+        }
 
         throw new NotImplementedException(sprintf(
             '%s : The element of the class `%s` has no tag name',

tests/Math/Writer/MathMLTest.php

@@ -80,6 +80,35 @@ public function testWriteFraction(): void
         $this->assertIsSchemaMathMLValid($output);
     }
 
+    public function testWriteSemantics(): void
+    {
+        $opTimes = new Element\Operator('⁢');
+
+        $math = new Math();
+
+        $semantics = new Element\Semantics();
+        $semantics->add(new Element\Identifier('y'));
+        $semantics->addAnnotation('application/x-tex', ' y ');
+
+        $math->add($semantics);
+
+        $writer = new MathML();
+        $output = $writer->write($math);
+
+        $expected = '<?xml version="1.0" encoding="UTF-8"?>'
+            . PHP_EOL
+            . '<!DOCTYPE math PUBLIC "-//W3C//DTD MathML 2.0//EN" "http://www.w3.org/Math/DTD/mathml2/mathml2.dtd">'
+            . '<math xmlns="http://www.w3.org/1998/Math/MathML">'
+            . '<semantics>'
+            . '<mi>y</mi>'
+            . '<annotation encoding="application/x-tex"> y </annotation>'
+            . '</semantics>'
+            . '</math>'
+            . PHP_EOL;
+        $this->assertEquals($expected, $output);
+        $this->assertIsSchemaMathMLValid($output);
+    }
+
     public function testWriteNotImplemented(): void
     {
         $this->expectException(NotImplementedException::class);