update xlsx reader

src/Spout/Reader/XLSX/Helper/CellValueFormatter.php

@@ -23,6 +23,7 @@ class CellValueFormatter
 
     /** Definition of XML nodes names used to parse data */
     const XML_NODE_VALUE = 'v';
+    const XML_NODE_FORMULA = 'f';
     const XML_NODE_INLINE_STRING_VALUE = 't';
 
     /** Definition of XML attributes used to parse data */
@@ -107,6 +108,21 @@ class CellValueFormatter
         }
     }
 
+    /**
+     * Returns the cell formula associated to the given XML node.
+     *
+     * @param \DOMNode $node
+     * @return string The formula associated with the cell
+     */
+    public function extractNodeFormula($node)
+    {
+        // for cell types having a "f" tag containing the formula.
+        // if not, the returned formula should be empty string.
+        $vNode = $node->getElementsByTagName(self::XML_NODE_FORMULA)->item(0);
+
+        return ($vNode !== null) ? $vNode->nodeValue : '';
+    }
+
     /**
      * Returns the cell's string value from a node's nested value node
      *

src/Spout/Reader/XLSX/RowIterator.php

@@ -359,7 +359,9 @@ class RowIterator implements IteratorInterface
     {
         try {
             $cellValue = $this->cellValueFormatter->extractAndFormatNodeValue($node);
+            $cellFormula = $this->cellValueFormatter->extractNodeFormula($node);
             $cell = $this->entityFactory->createCell($cellValue);
+            $cell->setFormula($cellFormula);
         } catch (InvalidValueException $exception) {
             $cell = $this->entityFactory->createCell($exception->getInvalidValue());
             $cell->setType(Cell::TYPE_ERROR);