MathML Reader : Support for mrow in mfrac

docs/changes/0.2.0.md

@@ -6,12 +6,12 @@
 
 ## Bug fixes
 
-- N/A
+- MathML Reader : Support for mrow in mfrac by [@Progi1984](https://github/Progi1984) in [#16](https://github.com/PHPOffice/Math/pull/16)
 
 ## Miscellaneous
 
 - Github Action : Roave BC Check by [@Progi1984](https://github/Progi1984) in [#9](https://github.com/PHPOffice/Math/pull/9)
 - Bump actions/checkout from 2 to 4 by [@dependabot](https://github/dependabot) in [#10](https://github.com/PHPOffice/Math/pull/10)
 - Bump actions/setup-python from 2 to 4 by [@dependabot](https://github/dependabot) in [#11](https://github.com/PHPOffice/Math/pull/11)
 - Bump actions/setup-python from 4 to 5 by [@dependabot](https://github/dependabot) in [#12](https://github.com/PHPOffice/Math/pull/12)
-- Bump peaceiris/actions-gh-pages from 3 to 4 by [@dependabot](https://github/dependabot) in [#12](https://github.com/PHPOffice/Math/pull/13)
+- Bump peaceiris/actions-gh-pages from 3 to 4 by [@dependabot](https://github/dependabot) in [#13](https://github.com/PHPOffice/Math/pull/13)

src/Math/Reader/MathML.php

@@ -61,12 +61,7 @@ protected function parseNode(?DOMNode $nodeRowElement, $parent): void
                 continue;
             }
 
-            $element = $this->getElement($nodeElement);
-            $parent->add($element);
-
-            if ($element instanceof Element\AbstractGroupElement) {
-                $this->parseNode($nodeElement, $element);
-            }
+            $parent->add($this->getElement($nodeElement));
         }
     }
 
@@ -108,7 +103,11 @@ protected function getElement(DOMNode $nodeElement): Element\AbstractElement
 
                 return new Element\Operator($nodeValue);
             case 'mrow':
-                return new Element\Row();
+                $mrow = new Element\Row();
+
+                $this->parseNode($nodeElement, $mrow);
+
+                return $mrow;
             case 'msup':
                 $nodeList = $this->xpath->query('*', $nodeElement);
                 if ($nodeList && $nodeList->length == 2) {
@@ -124,7 +123,11 @@ protected function getElement(DOMNode $nodeElement): Element\AbstractElement
                     $nodeElement->nodeName
                 ));
             case 'semantics':
-                return new Element\Semantics();
+                $semantics = new Element\Semantics();
+
+                $this->parseNode($nodeElement, $semantics);
+
+                return $semantics;
             default:
                 throw new NotImplementedException(sprintf(
                     '%s : The tag `%s` is not implemented',

tests/Math/Reader/MathMLTest.php

@@ -165,6 +165,60 @@ public function testReadFractionInvalid(): void
         $math = $reader->read($content);
     }
 
+    public function testReadFractionWithRow(): void
+    {
+        $content = '<?xml version="1.0" encoding="UTF-8"?>
+        <!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">
+            <mfrac>
+                <mrow>
+                    <mn>3</mn>
+                    <mo>-</mo>
+                    <mi>x</mi>
+                </mrow>
+                <mn>2</mn>
+            </mfrac>
+        </math>';
+
+        $reader = new MathML();
+        $math = $reader->read($content);
+        $this->assertInstanceOf(Math::class, $math);
+
+        $elements = $math->getElements();
+        $this->assertCount(1, $elements);
+        $this->assertInstanceOf(Element\Fraction::class, $elements[0]);
+
+        /** @var Element\Fraction $element */
+        $element = $elements[0];
+
+        $this->assertInstanceOf(Element\Row::class, $element->getNumerator());
+        /** @var Element\Row $subElement */
+        $subElement = $element->getNumerator();
+
+        $subsubElements = $subElement->getElements();
+        $this->assertCount(3, $subsubElements);
+
+        /** @var Element\Numeric $subsubElement */
+        $subsubElement = $subsubElements[0];
+        $this->assertInstanceOf(Element\Numeric::class, $subsubElement);
+        $this->assertEquals('3', $subsubElement->getValue());
+
+        /** @var Element\Operator $subsubElement */
+        $subsubElement = $subsubElements[1];
+        $this->assertInstanceOf(Element\Operator::class, $subsubElement);
+        $this->assertEquals('-', $subsubElement->getValue());
+
+        /** @var Element\Identifier $subsubElement */
+        $subsubElement = $subsubElements[2];
+        $this->assertInstanceOf(Element\Identifier::class, $subsubElement);
+        $this->assertEquals('x', $subsubElement->getValue());
+
+        $this->assertInstanceOf(Element\Numeric::class, $element->getDenominator());
+        /** @var Element\Numeric $subElement */
+        $subElement = $element->getDenominator();
+        $this->assertEquals('2', $subElement->getValue());
+    }
+
     public function testReadSuperscriptInvalid(): void
     {
         $this->expectException(InvalidInputException::class);