From a2be574f3678ec41bcb99094e13d7785921aa806 Mon Sep 17 00:00:00 2001
From: Roman Devman <info@roman-m.ru>
Date: Tue, 19 Oct 2021 18:13:57 +0300
Subject: [PATCH] Restore imperfect array formula values in xlsx writer

oleibman said:

The results of uncommenting the statements will often not be successful.
In Excel, if I enter `=MINVERSE({2,0;0,1})` into cell A1, you will get a
`dynamic array` (which we do not yet support) - A1 will contain 0.5, A2
and B1 will contain 0, and B2 will contain 1. There are also `spill`
implications for such a formula. The XML for these cells will be:

``` xml
<row r="1" spans="1:2" x14ac:dyDescent="0.3">
<c r="A1" cm="1">
<f t="array" ref="A1:B2">MINVERSE({2,0;0,1})</f>
<v>0.5</v>
</c>
<c r="B1">
<v>0</v>
</c>
</row>
<row r="2" spans="1:2" x14ac:dyDescent="0.3">
<c r="A2">
<v>0</v>
</c>
<c r="B2">
<v>1</v>
</c>
</row>
```

I believe that the PhpSpreadsheet equivalent of doing this (with the statements
uncommented) is:

```php
        $spreadsheet = new Spreadsheet();
        $calculation = Calculation::getInstance($spreadsheet);
        $calculation::setArrayReturnType(Calculation::RETURN_ARRAY_AS_ARRAY);
        $sheet = $spreadsheet->getActiveSheet();
        $sheet->getCell('A1')->setValue('=MINVERSE({2,0;0,1})');
        $writer = new Xlsx($spreadsheet);
        $oufil = 'issue.2343.xlsx';
        $writer->save($oufil);
```

But our output file only fills in A1:

```xml
<row r="1" spans="1:1">
<c r="A1">
<f>MINVERSE({2,0;0,1})</f>
<v>0.5</v>
</c>
</row>
```

And, even though A1 has its correct value, note that its `f` tag does not have
a `t` attribute. This is because we never set any formula attributes, except
in Xlsx Reader (see next paragraph), so we do not encounter the `'array'`
condtion for a formula newly added to a spreadsheet.

We do slightly better when we read the first file (as opposed to creating a new
spreadsheet), but we succeed only by accident. Because B1, A2, and B2 are
assigned values in the XML, all 4 cells will have the expected values. But they
are now independent of each other, not part of a dynamic array. When we write
this out, it is almost correct:

```xml
<row r="1" spans="1:2">
<c r="A1">
<f>MINVERSE({2,0;0,1})</f>
<v>0.5</v>
</c>
<c r="B1">
<v>0</v>
</c>
</row>
<row r="2" spans="1:2">
<c r="A2">
<v>0</v>
</c>
<c r="B2">
<v>1</v>
</c>
</row>
```

Again, the `f` tag has no `t` attribute, and it doesn't seem to matter whether we set
RETURN_TYPE_ARRAY or not. I think this particular aspect of the problem might be
relatively easy to fix.
---
 src/PhpSpreadsheet/Writer/Xlsx/Worksheet.php | 41 ++++++++++----------
 1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/src/PhpSpreadsheet/Writer/Xlsx/Worksheet.php b/src/PhpSpreadsheet/Writer/Xlsx/Worksheet.php
index 204c4953..3e1b537e 100644
--- a/src/PhpSpreadsheet/Writer/Xlsx/Worksheet.php
+++ b/src/PhpSpreadsheet/Writer/Xlsx/Worksheet.php
@@ -1205,27 +1205,26 @@ class Worksheet extends WriterPart
             $objWriter->writeAttribute('t', 'b');
             $calculatedValue = (int) $calculatedValue;
         }
-        // array values are not yet supported
-        //$attributes = $pCell->getFormulaAttributes();
-        //if (($attributes['t'] ?? null) === 'array') {
-        //    $objWriter->startElement('f');
-        //    $objWriter->writeAttribute('t', 'array');
-        //    $objWriter->writeAttribute('ref', $pCellAddress);
-        //    $objWriter->writeAttribute('aca', '1');
-        //    $objWriter->writeAttribute('ca', '1');
-        //    $objWriter->text(substr($cellValue, 1));
-        //    $objWriter->endElement();
-        //} else {
-        //    $objWriter->writeElement('f', Xlfn::addXlfnStripEquals($cellValue));
-        //}
-        $objWriter->writeElement('f', Xlfn::addXlfnStripEquals($cellValue));
-        self::writeElementIf(
-            $objWriter,
-            $this->getParentWriter()->getOffice2003Compatibility() === false,
-            'v',
-            ($this->getParentWriter()->getPreCalculateFormulas() && !is_array($calculatedValue) && substr($calculatedValue ?? '', 0, 1) !== '#')
-                ? StringHelper::formatNumber($calculatedValue) : '0'
-        );
+
+        $attributes = $cell->getFormulaAttributes();
+        if (($attributes['t'] ?? null) === 'array') {
+            $objWriter->startElement('f');
+            $objWriter->writeAttribute('t', 'array');
+            $objWriter->writeAttribute('ref', $cell->getCoordinate());
+            $objWriter->writeAttribute('aca', '1');
+            $objWriter->writeAttribute('ca', '1');
+            $objWriter->text(substr($cellValue, 1));
+            $objWriter->endElement();
+        } else {
+            $objWriter->writeElement('f', Xlfn::addXlfnStripEquals($cellValue));
+            self::writeElementIf(
+                $objWriter,
+                $this->getParentWriter()->getOffice2003Compatibility() === false,
+                'v',
+                ($this->getParentWriter()->getPreCalculateFormulas() && !is_array($calculatedValue) && substr($calculatedValue, 0, 1) !== '#')
+                    ? StringHelper::formatNumber($calculatedValue) : '0'
+            );
+        }
     }
 
     /**