diff --git a/composer.lock b/composer.lock
index c50914164..cc01138c6 100644
--- a/composer.lock
+++ b/composer.lock
@@ -1798,16 +1798,16 @@
         },
         {
             "name": "phpstan/phpstan",
-            "version": "2.1.11",
+            "version": "2.1.13",
             "source": {
                 "type": "git",
                 "url": "https://github.com/phpstan/phpstan.git",
-                "reference": "8ca5f79a8f63c49b2359065832a654e1ec70ac30"
+                "reference": "e55e03e6d4ac49cd1240907e5b08e5cd378572a9"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/phpstan/phpstan/zipball/8ca5f79a8f63c49b2359065832a654e1ec70ac30",
-                "reference": "8ca5f79a8f63c49b2359065832a654e1ec70ac30",
+                "url": "https://api.github.com/repos/phpstan/phpstan/zipball/e55e03e6d4ac49cd1240907e5b08e5cd378572a9",
+                "reference": "e55e03e6d4ac49cd1240907e5b08e5cd378572a9",
                 "shasum": ""
             },
             "require": {
@@ -1852,25 +1852,25 @@
                     "type": "github"
                 }
             ],
-            "time": "2025-03-24T13:45:00+00:00"
+            "time": "2025-04-27T12:28:25+00:00"
         },
         {
             "name": "phpstan/phpstan-deprecation-rules",
-            "version": "2.0.1",
+            "version": "2.0.2",
             "source": {
                 "type": "git",
                 "url": "https://github.com/phpstan/phpstan-deprecation-rules.git",
-                "reference": "1cc1259cb91ee4cfbb5c39bca9f635f067c910b4"
+                "reference": "9d8e7d4e32711715ad78a1fb6ec368df9af01fdf"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/phpstan/phpstan-deprecation-rules/zipball/1cc1259cb91ee4cfbb5c39bca9f635f067c910b4",
-                "reference": "1cc1259cb91ee4cfbb5c39bca9f635f067c910b4",
+                "url": "https://api.github.com/repos/phpstan/phpstan-deprecation-rules/zipball/9d8e7d4e32711715ad78a1fb6ec368df9af01fdf",
+                "reference": "9d8e7d4e32711715ad78a1fb6ec368df9af01fdf",
                 "shasum": ""
             },
             "require": {
                 "php": "^7.4 || ^8.0",
-                "phpstan/phpstan": "^2.0"
+                "phpstan/phpstan": "^2.1.13"
             },
             "require-dev": {
                 "php-parallel-lint/php-parallel-lint": "^1.2",
@@ -1897,9 +1897,9 @@
             "description": "PHPStan rules for detecting usage of deprecated classes, methods, properties, constants and traits.",
             "support": {
                 "issues": "https://github.com/phpstan/phpstan-deprecation-rules/issues",
-                "source": "https://github.com/phpstan/phpstan-deprecation-rules/tree/2.0.1"
+                "source": "https://github.com/phpstan/phpstan-deprecation-rules/tree/2.0.2"
             },
-            "time": "2024-11-28T21:56:36+00:00"
+            "time": "2025-04-26T19:59:57+00:00"
         },
         {
             "name": "phpstan/phpstan-phpunit",
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 364905f71..aab499115 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -1,2 +1,2 @@
 parameters:
-	ignoreErrors:
+	ignoreErrors: []
diff --git a/src/PhpSpreadsheet/Cell/AdvancedValueBinder.php b/src/PhpSpreadsheet/Cell/AdvancedValueBinder.php
index 7c2f989b8..1db0c0f5a 100644
--- a/src/PhpSpreadsheet/Cell/AdvancedValueBinder.php
+++ b/src/PhpSpreadsheet/Cell/AdvancedValueBinder.php
@@ -110,7 +110,7 @@ class AdvancedValueBinder extends DefaultValueBinder implements IValueBinder
         return parent::bindValue($cell, $value);
     }
 
-    /** @param array{0: non-falsy-string, 1: ?string, 2: numeric-string, 3: numeric-string, 4: numeric-string} $matches */
+    /** @param array{0: string, 1: ?string, 2: numeric-string, 3: numeric-string, 4: numeric-string} $matches */
     protected function setImproperFraction(array $matches, Cell $cell): bool
     {
         // Convert value to number
@@ -131,7 +131,7 @@ class AdvancedValueBinder extends DefaultValueBinder implements IValueBinder
         return true;
     }
 
-    /** @param array{0: non-falsy-string, 1: ?string, 2: numeric-string, 3: numeric-string} $matches */
+    /** @param array{0: string, 1: ?string, 2: numeric-string, 3: numeric-string} $matches */
     protected function setProperFraction(array $matches, Cell $cell): bool
     {
         // Convert value to number
diff --git a/src/PhpSpreadsheet/Cell/Cell.php b/src/PhpSpreadsheet/Cell/Cell.php
index 704352456..08175fc1e 100644
--- a/src/PhpSpreadsheet/Cell/Cell.php
+++ b/src/PhpSpreadsheet/Cell/Cell.php
@@ -497,10 +497,9 @@ class Cell implements Stringable
                                 if (isset($matches[3])) {
                                     $minCol = $matches[1];
                                     $minRow = (int) $matches[2];
-                                    // https://github.com/phpstan/phpstan/issues/11602
-                                    $maxCol = $matches[4]; // @phpstan-ignore-line
+                                    $maxCol = $matches[4];
                                     ++$maxCol;
-                                    $maxRow = (int) $matches[5]; // @phpstan-ignore-line
+                                    $maxRow = (int) $matches[5];
                                     for ($row = $minRow; $row <= $maxRow; ++$row) {
                                         for ($col = $minCol; $col !== $maxCol; ++$col) {
                                             if ("$col$row" !== $coordinate) {
diff --git a/src/PhpSpreadsheet/Chart/ChartColor.php b/src/PhpSpreadsheet/Chart/ChartColor.php
index d6306de6b..6ac4b5acf 100644
--- a/src/PhpSpreadsheet/Chart/ChartColor.php
+++ b/src/PhpSpreadsheet/Chart/ChartColor.php
@@ -22,7 +22,7 @@ class ChartColor
     private ?int $brightness = null;
 
     /**
-     * @param string|string[] $value
+     * @param array{value: ?string, alpha: null|int|string, brightness?: null|int|string, type: ?string}|string  $value
      */
     public function __construct($value = '', ?int $alpha = null, ?string $type = null, ?int $brightness = null)
     {
@@ -114,6 +114,7 @@ class ChartColor
         return $this;
     }
 
+    /** @param array{value: ?string, alpha: null|int|string, brightness?: null|int|string, type: ?string}  $color */
     public function setColorPropertiesArray(array $color): self
     {
         return $this->setColorProperties(
diff --git a/src/PhpSpreadsheet/Chart/Properties.php b/src/PhpSpreadsheet/Chart/Properties.php
index 3e02a964f..64f97d53c 100644
--- a/src/PhpSpreadsheet/Chart/Properties.php
+++ b/src/PhpSpreadsheet/Chart/Properties.php
@@ -177,6 +177,7 @@ abstract class Properties
         return ((float) $value) / self::PERCENTAGE_MULTIPLIER;
     }
 
+    /** @return array{type: ?string, value: ?string, alpha: ?int} */
     protected function setColorProperties(?string $color, null|float|int|string $alpha, ?string $colorType): array
     {
         return [
@@ -506,11 +507,14 @@ abstract class Properties
         return $this->softEdges['size'];
     }
 
+    /** @param null|array{value?: ?string, alpha?: null|int|string, brightness?: null|int|string, type?: ?string}|float|string  $value */
     public function setShadowProperty(string $propertyName, mixed $value): self
     {
         $this->activateObject();
         if ($propertyName === 'color' && is_array($value)) {
-            $this->shadowColor->setColorPropertiesArray($value);
+            /** @var array{value: ?string, alpha: null|int|string, brightness?: null|int|string, type: ?string} */
+            $valuex = $value;
+            $this->shadowColor->setColorPropertiesArray($valuex);
         } else {
             $this->shadowProperties[$propertyName] = $value;
         }
diff --git a/src/PhpSpreadsheet/Helper/Html.php b/src/PhpSpreadsheet/Helper/Html.php
index 46fdd7547..b668206e3 100644
--- a/src/PhpSpreadsheet/Helper/Html.php
+++ b/src/PhpSpreadsheet/Helper/Html.php
@@ -557,6 +557,7 @@ class Html
     /** @var callable[] */
     protected array $endTagCallbacks;
 
+    /** @var mixed[] */
     private array $stack = [];
 
     public string $stringData = '';
@@ -711,7 +712,10 @@ class Html
 
     public static function colourNameLookup(string $colorName): string
     {
-        return static::COLOUR_MAP[$colorName] ?? '';
+        /** @var string[] */
+        $temp = static::COLOUR_MAP;
+
+        return $temp[$colorName] ?? '';
     }
 
     protected function startFontTag(DOMElement $tag): void
diff --git a/src/PhpSpreadsheet/Helper/Sample.php b/src/PhpSpreadsheet/Helper/Sample.php
index 7176696dd..729d5d736 100644
--- a/src/PhpSpreadsheet/Helper/Sample.php
+++ b/src/PhpSpreadsheet/Helper/Sample.php
@@ -241,6 +241,7 @@ class Sample
             : $this->log(sprintf('Function: %s() - %s.', rtrim($functionName, '()'), rtrim($description, '.')));
     }
 
+    /** @param mixed[][] $matrix */
     public function displayGrid(array $matrix): void
     {
         $renderer = new TextGrid($matrix, $this->isCli());
diff --git a/src/PhpSpreadsheet/Helper/TextGrid.php b/src/PhpSpreadsheet/Helper/TextGrid.php
index c7868c050..9c64c617c 100644
--- a/src/PhpSpreadsheet/Helper/TextGrid.php
+++ b/src/PhpSpreadsheet/Helper/TextGrid.php
@@ -8,10 +8,13 @@ class TextGrid
 {
     private bool $isCli;
 
+    /** @var mixed[][] */
     protected array $matrix;
 
+    /** @var int[] */
     protected array $rows;
 
+    /** @var string[] */
     protected array $columns;
 
     private string $gridDisplay;
@@ -22,6 +25,7 @@ class TextGrid
 
     private bool $columnHeaders = true;
 
+    /** @param mixed[][] $matrix */
     public function __construct(array $matrix, bool $isCli = true, bool $rowDividers = false, bool $rowHeaders = true, bool $columnHeaders = true)
     {
         $this->rows = array_keys($matrix);
@@ -63,6 +67,7 @@ class TextGrid
         return $this->gridDisplay;
     }
 
+    /** @param int[] $columnWidths */
     private function renderRows(int $maxRowLength, array $columnWidths): void
     {
         foreach ($this->matrix as $row => $rowData) {
@@ -77,6 +82,10 @@ class TextGrid
         }
     }
 
+    /**
+     * @param mixed[] $rowData
+     * @param int[] $columnWidths
+     */
     private function renderCells(array $rowData, array $columnWidths): void
     {
         foreach ($rowData as $column => $cell) {
@@ -87,6 +96,7 @@ class TextGrid
         }
     }
 
+    /** @param int[] $columnWidths */
     private function renderColumnHeader(int $maxRowLength, array &$columnWidths): void
     {
         if (!$this->columnHeaders) {
@@ -95,6 +105,7 @@ class TextGrid
             return;
         }
         foreach ($this->columns as $column => $reference) {
+            /** @var string $reference */
             $columnWidths[$column] = max($columnWidths[$column], $this->strlen($reference));
         }
         if ($this->rowHeaders) {
@@ -109,6 +120,7 @@ class TextGrid
             $this->gridDisplay .= str_repeat(' ', $maxRowLength + 2);
         }
         foreach ($this->columns as $column => $reference) {
+            /** @var scalar $reference */
             $this->gridDisplay .= '| ' . str_pad((string) $reference, $columnWidths[$column] + 1, ' ');
         }
         $this->gridDisplay .= '|' . PHP_EOL;
@@ -116,6 +128,7 @@ class TextGrid
         $this->renderFooter($maxRowLength, $columnWidths);
     }
 
+    /** @param int[] $columnWidths */
     private function renderFooter(int $maxRowLength, array $columnWidths): void
     {
         if ($this->rowHeaders) {
@@ -128,6 +141,7 @@ class TextGrid
         $this->gridDisplay .= '+' . PHP_EOL;
     }
 
+    /** @return int[] */
     private function getColumnWidths(): array
     {
         $columnCount = count($this->matrix, COUNT_RECURSIVE) / count($this->matrix);
@@ -139,6 +153,7 @@ class TextGrid
         return $columnWidths;
     }
 
+    /** @param mixed[] $columnData */
     private function getColumnWidth(array $columnData): int
     {
         $columnWidth = 0;
diff --git a/src/PhpSpreadsheet/IOFactory.php b/src/PhpSpreadsheet/IOFactory.php
index 73734fc70..e16cf62b2 100644
--- a/src/PhpSpreadsheet/IOFactory.php
+++ b/src/PhpSpreadsheet/IOFactory.php
@@ -116,6 +116,8 @@ abstract class IOFactory
 
     /**
      * Identify file type using automatic IReader resolution.
+     *
+     * @param string[] $readers
      */
     public static function identify(string $filename, ?array $readers = null, bool $fullClassName = false): string
     {
diff --git a/src/PhpSpreadsheet/NamedRange.php b/src/PhpSpreadsheet/NamedRange.php
index 819ddeac6..c7fb853df 100644
--- a/src/PhpSpreadsheet/NamedRange.php
+++ b/src/PhpSpreadsheet/NamedRange.php
@@ -43,6 +43,7 @@ class NamedRange extends DefinedName
         return $this;
     }
 
+    /** @return string[] */
     public function getCellsInRange(): array
     {
         $range = $this->value;
diff --git a/src/PhpSpreadsheet/Reader/Csv.php b/src/PhpSpreadsheet/Reader/Csv.php
index f4cdd02d3..783c4f00c 100644
--- a/src/PhpSpreadsheet/Reader/Csv.php
+++ b/src/PhpSpreadsheet/Reader/Csv.php
@@ -188,7 +188,8 @@ class Csv extends BaseReader
      */
     protected function inferSeparator(): void
     {
-        if ($this->delimiter !== null) {
+        $temp = $this->delimiter;
+        if ($temp !== null) {
             return;
         }
 
@@ -228,13 +229,15 @@ class Csv extends BaseReader
         $this->checkSeparator();
         $this->inferSeparator();
 
-        /** @var array<int, array{worksheetName: string, lastColumnLetter: string, lastColumnIndex: int, totalRows: int, totalColumns: int, sheetState: string}> */
-        $worksheetInfo = [];
-        $worksheetInfo[0]['worksheetName'] = 'Worksheet';
-        $worksheetInfo[0]['lastColumnLetter'] = 'A';
-        $worksheetInfo[0]['lastColumnIndex'] = 0;
-        $worksheetInfo[0]['totalRows'] = 0;
-        $worksheetInfo[0]['totalColumns'] = 0;
+        $worksheetInfo = [
+            [
+                'worksheetName' => 'Worksheet',
+                'lastColumnLetter' => 'A',
+                'lastColumnIndex' => 0,
+                'totalRows' => 0,
+                'totalColumns' => 0,
+            ],
+        ];
         $delimiter = $this->delimiter ?? '';
 
         // Loop through each line of the file in turn
diff --git a/src/PhpSpreadsheet/Reader/Html.php b/src/PhpSpreadsheet/Reader/Html.php
index 55f97d327..eb39752bf 100644
--- a/src/PhpSpreadsheet/Reader/Html.php
+++ b/src/PhpSpreadsheet/Reader/Html.php
@@ -51,7 +51,7 @@ class Html extends BaseReader
     /**
      * Formats.
      */
-    protected array $formats = [
+    protected const FORMATS = [
         'h1' => [
             'font' => [
                 'bold' => true,
@@ -128,6 +128,7 @@ class Html extends BaseReader
         ], //    Italic
     ];
 
+    /** @var array<string, bool> */
     protected array $rowspan = [];
 
     /**
@@ -218,12 +219,17 @@ class Html extends BaseReader
         return $this->loadIntoExisting($filename, $spreadsheet);
     }
 
-    //    Data Array used for testing only, should write to Spreadsheet object on completion of tests
-
+    /**
+     * Data Array used for testing only, should write to
+     * Spreadsheet object on completion of tests.
+     *
+     * @var mixed[][]
+     */
     protected array $dataArray = [];
 
     protected int $tableLevel = 0;
 
+    /** @var string[] */
     protected array $nestedColumn = ['A'];
 
     protected function setTableStartColumn(string $column): string
@@ -246,12 +252,14 @@ class Html extends BaseReader
     {
         --$this->tableLevel;
 
-        return array_pop($this->nestedColumn);
+        return array_pop($this->nestedColumn) ?? '';
     }
 
     /**
      * Flush cell.
      *
+     * @param string[] $attributeArray
+     *
      * @param-out string $cellContent In one case, it can be bool
      */
     protected function flushCell(Worksheet $sheet, string $column, int|string $row, mixed &$cellContent, array $attributeArray): void
@@ -345,6 +353,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementTitle(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'title') {
@@ -364,6 +373,7 @@ class Html extends BaseReader
 
     private const SPAN_ETC = ['span', 'div', 'font', 'i', 'em', 'strong', 'b'];
 
+    /** @param string[] $attributeArray */
     private function processDomElementSpanEtc(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if (in_array((string) $child->nodeName, self::SPAN_ETC, true)) {
@@ -376,7 +386,7 @@ class Html extends BaseReader
                 }
                 if (isset($attributeArray['style'])) {
                     $alignStyle = $attributeArray['style'];
-                    if (preg_match('/\btext-align:\s*(left|right|center|justify)\b/', $alignStyle, $matches) === 1) {
+                    if (preg_match('/\btext-align:\s*(left|right|center|justify)\b/', (string) $alignStyle, $matches) === 1) {
                         $sheet->getComment($column . $row)->setAlignment($matches[1]);
                     }
                 }
@@ -384,28 +394,28 @@ class Html extends BaseReader
                 $this->processDomElement($child, $sheet, $row, $column, $cellContent);
             }
 
-            if (isset($this->formats[$child->nodeName])) {
-                $sheet->getStyle($column . $row)->applyFromArray($this->formats[$child->nodeName]);
+            if (isset(self::FORMATS[$child->nodeName])) {
+                $sheet->getStyle($column . $row)->applyFromArray(self::FORMATS[$child->nodeName]);
             }
         } else {
             $this->processDomElementHr($sheet, $row, $column, $cellContent, $child, $attributeArray);
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementHr(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'hr') {
             $this->flushCell($sheet, $column, $row, $cellContent, $attributeArray);
             ++$row;
-            if (isset($this->formats[$child->nodeName])) {
-                $sheet->getStyle($column . $row)->applyFromArray($this->formats[$child->nodeName]);
-            }
+            $sheet->getStyle($column . $row)->applyFromArray(self::FORMATS[$child->nodeName]);
             ++$row;
         }
         // fall through to br
         $this->processDomElementBr($sheet, $row, $column, $cellContent, $child, $attributeArray);
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementBr(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'br' || $child->nodeName === 'hr') {
@@ -423,6 +433,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementA(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'a') {
@@ -430,9 +441,7 @@ class Html extends BaseReader
                 switch ($attributeName) {
                     case 'href':
                         $sheet->getCell($column . $row)->getHyperlink()->setUrl($attributeValue);
-                        if (isset($this->formats[$child->nodeName])) {
-                            $sheet->getStyle($column . $row)->applyFromArray($this->formats[$child->nodeName]);
-                        }
+                        $sheet->getStyle($column . $row)->applyFromArray(self::FORMATS[$child->nodeName]);
 
                         break;
                     case 'class':
@@ -451,6 +460,7 @@ class Html extends BaseReader
 
     private const H1_ETC = ['h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'ol', 'ul', 'p'];
 
+    /** @param string[] $attributeArray */
     private function processDomElementH1Etc(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if (in_array((string) $child->nodeName, self::H1_ETC, true)) {
@@ -467,8 +477,8 @@ class Html extends BaseReader
                 $this->processDomElement($child, $sheet, $row, $column, $cellContent);
                 $this->flushCell($sheet, $column, $row, $cellContent, $attributeArray);
 
-                if (isset($this->formats[$child->nodeName])) {
-                    $sheet->getStyle($column . $row)->applyFromArray($this->formats[$child->nodeName]);
+                if (isset(self::FORMATS[$child->nodeName])) {
+                    $sheet->getStyle($column . $row)->applyFromArray(self::FORMATS[$child->nodeName]);
                 }
 
                 ++$row;
@@ -479,6 +489,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementLi(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'li') {
@@ -500,6 +511,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementImg(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'img') {
@@ -511,6 +523,7 @@ class Html extends BaseReader
 
     private string $currentColumn = 'A';
 
+    /** @param string[] $attributeArray */
     private function processDomElementTable(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'table') {
@@ -537,6 +550,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementTr(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName === 'col') {
@@ -548,7 +562,7 @@ class Html extends BaseReader
             $this->processDomElement($child, $sheet, $row, $column, $cellContent);
 
             if (isset($attributeArray['height'])) {
-                $sheet->getRowDimension($row)->setRowHeight($attributeArray['height']);
+                $sheet->getRowDimension($row)->setRowHeight((float) $attributeArray['height']);
             }
 
             ++$row;
@@ -557,6 +571,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementThTdOther(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         if ($child->nodeName !== 'td' && $child->nodeName !== 'th') {
@@ -566,6 +581,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementBgcolor(Worksheet $sheet, int $row, string $column, array $attributeArray): void
     {
         if (isset($attributeArray['bgcolor'])) {
@@ -580,6 +596,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementWidth(Worksheet $sheet, string $column, array $attributeArray): void
     {
         if (isset($attributeArray['width'])) {
@@ -587,6 +604,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementHeight(Worksheet $sheet, int $row, array $attributeArray): void
     {
         if (isset($attributeArray['height'])) {
@@ -594,6 +612,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementAlign(Worksheet $sheet, int $row, string $column, array $attributeArray): void
     {
         if (isset($attributeArray['align'])) {
@@ -601,6 +620,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementVAlign(Worksheet $sheet, int $row, string $column, array $attributeArray): void
     {
         if (isset($attributeArray['valign'])) {
@@ -608,6 +628,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementDataFormat(Worksheet $sheet, int $row, string $column, array $attributeArray): void
     {
         if (isset($attributeArray['data-format'])) {
@@ -615,6 +636,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $attributeArray */
     private function processDomElementThTd(Worksheet $sheet, int &$row, string &$column, string &$cellContent, DOMElement $child, array &$attributeArray): void
     {
         while (isset($this->rowspan[$column . $row])) {
@@ -640,6 +662,7 @@ class Html extends BaseReader
             //create merging rowspan and colspan
             $columnTo = $column;
             for ($i = 0; $i < (int) $attributeArray['colspan'] - 1; ++$i) {
+                /** @var string $columnTo */
                 ++$columnTo;
             }
             $range = $column . $row . ':' . $columnTo . ($row + (int) $attributeArray['rowspan'] - 1);
@@ -660,6 +683,7 @@ class Html extends BaseReader
             //create merging colspan
             $columnTo = $column;
             for ($i = 0; $i < (int) $attributeArray['colspan'] - 1; ++$i) {
+                /** @var string $columnTo */
                 ++$columnTo;
             }
             $sheet->mergeCells($column . $row . ':' . $columnTo . $row);
@@ -667,7 +691,7 @@ class Html extends BaseReader
             $column = $columnTo; // ++$columnTo above confuses phpstan
         }
 
-        ++$column;
+        ++$column; //* @phpstan-ignore-line
     }
 
     protected function processDomElement(DOMNode $element, Worksheet $sheet, int &$row, string &$column, string &$cellContent): void
@@ -792,6 +816,7 @@ class Html extends BaseReader
         }
     }
 
+    /** @param string[] $matches */
     private static function replaceNonAscii(array $matches): string
     {
         return '&#' . mb_ord($matches[0], 'UTF-8') . ';';
@@ -891,6 +916,8 @@ class Html extends BaseReader
      *
      * TODO :
      * - Implement to other propertie, such as border
+     *
+     * @param string[] $attributeArray
      */
     private function applyInlineStyle(Worksheet &$sheet, int $row, string $column, array $attributeArray): void
     {
@@ -903,6 +930,7 @@ class Html extends BaseReader
         } elseif (isset($attributeArray['rowspan'], $attributeArray['colspan'])) {
             $columnTo = $column;
             for ($i = 0; $i < (int) $attributeArray['colspan'] - 1; ++$i) {
+                /** @var string $columnTo */
                 ++$columnTo;
             }
             $range = $column . $row . ':' . $columnTo . ($row + (int) $attributeArray['rowspan'] - 1);
@@ -913,6 +941,7 @@ class Html extends BaseReader
         } elseif (isset($attributeArray['colspan'])) {
             $columnTo = $column;
             for ($i = 0; $i < (int) $attributeArray['colspan'] - 1; ++$i) {
+                /** @var string $columnTo */
                 ++$columnTo;
             }
             $range = $column . $row . ':' . $columnTo . $row;
@@ -1079,6 +1108,7 @@ class Html extends BaseReader
         return HelperHtml::colourNameLookup($value);
     }
 
+    /** @param string[] $attributes */
     private function insertImage(Worksheet $sheet, string $column, int $row, array $attributes): void
     {
         if (!isset($attributes['src'])) {
@@ -1109,6 +1139,8 @@ class Html extends BaseReader
             $drawing->setName($name);
         }
 
+        /** @var null|scalar $width */
+        /** @var null|scalar $height */
         if ($width) {
             if ($height) {
                 $drawing->setWidthAndHeight((int) $width, (int) $height);
@@ -1135,6 +1167,11 @@ class Html extends BaseReader
         }
     }
 
+    /**
+     * @param string[] $attributes
+     *
+     * @return mixed[]
+     */
     private static function getStyleArray(array $attributes): array
     {
         $styleArray = [];
@@ -1183,6 +1220,7 @@ class Html extends BaseReader
         'thick' => Border::BORDER_THICK,
     ];
 
+    /** @return array<string, string> */
     public static function getBorderMappings(): array
     {
         return self::BORDER_MAPPINGS;
diff --git a/src/PhpSpreadsheet/Reader/Xls.php b/src/PhpSpreadsheet/Reader/Xls.php
index d1e3cdb99..ae0460361 100644
--- a/src/PhpSpreadsheet/Reader/Xls.php
+++ b/src/PhpSpreadsheet/Reader/Xls.php
@@ -104,6 +104,8 @@ class Xls extends XlsBase
 
     /**
      * Shared formats.
+     *
+     * @var mixed[]
      */
     protected array $formats;
 
@@ -116,36 +118,50 @@ class Xls extends XlsBase
 
     /**
      * Color palette.
+     *
+     * @var string[][]
      */
     protected array $palette;
 
     /**
      * Worksheets.
+     *
+     * @var array<array{name: string, offset: int, sheetState: string, sheetType: int|string}>
      */
     protected array $sheets;
 
     /**
      * External books.
+     *
+     * @var mixed[][]
      */
     protected array $externalBooks;
 
     /**
      * REF structures. Only applies to BIFF8.
+     *
+     * @var mixed[][]
      */
     protected array $ref;
 
     /**
      * External names.
+     *
+     * @var array<array<string, mixed>|string>
      */
     protected array $externalNames;
 
     /**
      * Defined names.
+     *
+     * @var array{isBuiltInName: int, name: string, formula: string, scope: int}
      */
     protected array $definedname;
 
     /**
      * Shared strings. Only applies to BIFF8.
+     *
+     * @var array<array{value: string, fmtRuns: mixed[]}>
      */
     protected array $sst;
 
@@ -161,16 +177,22 @@ class Xls extends XlsBase
 
     /**
      * Objects. One OBJ record contributes with one entry.
+     *
+     * @var mixed[]
      */
     protected array $objs;
 
     /**
      * Text Objects. One TXO record corresponds with one entry.
+     *
+     * @var array<array{text: string, format: string, alignment: int, rotation: int}>
      */
     protected array $textObjects;
 
     /**
      * Cell Annotations (BIFF8).
+     *
+     * @var mixed[]
      */
     protected array $cellNotes;
 
@@ -191,22 +213,30 @@ class Xls extends XlsBase
 
     /**
      * Mapping of XF index (that is a cell XF) to final index in cellXf collection.
+     *
+     * @var int[]
      */
     protected array $mapCellXfIndex;
 
     /**
      * Mapping of XF index (that is a style XF) to final index in cellStyleXf collection.
+     *
+     * @var int[]
      */
     protected array $mapCellStyleXfIndex;
 
     /**
      * The shared formulas in a sheet. One SHAREDFMLA record contributes with one value.
+     *
+     * @var mixed[]
      */
     protected array $sharedFormulas;
 
     /**
      * The shared formula parts in a sheet. One FORMULA record contributes with one value if it
      * refers to a shared formula.
+     *
+     * @var mixed[]
      */
     protected array $sharedFormulaParts;
 
@@ -220,6 +250,8 @@ class Xls extends XlsBase
      */
     protected int $encryptionStartPos = 0;
 
+    protected string $encryptionPassword = 'VelvetSweatshop';
+
     /**
      * The current RC4 decryption object.
      */
@@ -232,7 +264,7 @@ class Xls extends XlsBase
 
     /**
      * The current MD5 context state.
-     * It is never set in the program, so code which uses it is suspect.
+     * It is set via call-by-reference to verifyPassword.
      */
     private string $md5Ctxt = '';
 
@@ -721,10 +753,18 @@ class Xls extends XlsBase
         $cbRuns = self::getUInt2d($recordData, 12);
         $text = $this->getSplicedRecordData();
 
-        $textByte = $text['spliceOffsets'][1] - $text['spliceOffsets'][0] - 1;
-        $textStr = substr($text['recordData'], $text['spliceOffsets'][0] + 1, $textByte);
+        /** @var int[] */
+        $tempSplice = $text['spliceOffsets'];
+        /** @var int */
+        $temp = $tempSplice[0];
+        /** @var int */
+        $temp1 = $tempSplice[1];
+        $textByte = $temp1 - $temp - 1;
+        /** @var string */
+        $textRecordData = $text['recordData'];
+        $textStr = substr($textRecordData, $temp + 1, $textByte);
         // get 1 byte
-        $is16Bit = ord($text['recordData'][0]);
+        $is16Bit = ord($textRecordData[0]);
         // it is possible to use a compressed format,
         // which omits the high bytes of all characters, if they are all zero
         if (($is16Bit & 0x01) === 0) {
@@ -735,7 +775,7 @@ class Xls extends XlsBase
 
         $this->textObjects[$this->textObjRef] = [
             'text' => $textStr,
-            'format' => substr($text['recordData'], $text['spliceOffsets'][1], $cbRuns),
+            'format' => substr($textRecordData, $tempSplice[1], $cbRuns),
             'alignment' => $grbitOpts,
             'rotation' => $rot,
         ];
@@ -780,6 +820,13 @@ class Xls extends XlsBase
         }
     }
 
+    public function setEncryptionPassword(string $encryptionPassword): self
+    {
+        $this->encryptionPassword = $encryptionPassword;
+
+        return $this;
+    }
+
     /**
      * FILEPASS.
      *
@@ -799,7 +846,7 @@ class Xls extends XlsBase
     {
         $length = self::getUInt2d($this->data, $this->pos + 2);
 
-        if ($length != 54) {
+        if ($length < 54) {
             throw new Exception('Unexpected file pass record length');
         }
 
@@ -808,7 +855,10 @@ class Xls extends XlsBase
         // move stream pointer to next record
         $this->pos += 4 + $length;
 
-        if (!$this->verifyPassword('VelvetSweatshop', substr($recordData, 6, 16), substr($recordData, 22, 16), substr($recordData, 38, 16), $this->md5Ctxt)) {
+        if (substr($recordData, 0, 2) !== "\x01\x00" || substr($recordData, 4, 2) !== "\x01\x00") {
+            throw new Exception('Unsupported encryption algorithm');
+        }
+        if (!$this->verifyPassword($this->encryptionPassword, substr($recordData, 6, 16), substr($recordData, 22, 16), substr($recordData, 38, 16), $this->md5Ctxt)) {
             throw new Exception('Decryption password incorrect');
         }
 
@@ -1046,6 +1096,7 @@ class Xls extends XlsBase
             } else {
                 $string = $this->readByteStringShort(substr($recordData, 14));
             }
+            /** @var string[] $string */
             $objFont->setName($string['value']);
 
             $this->objFonts[] = $objFont;
@@ -1142,7 +1193,9 @@ class Xls extends XlsBase
                 // we set the general format code
                 $numberFormat = ['formatCode' => NumberFormat::FORMAT_GENERAL];
             }
-            $objStyle->getNumberFormat()->setFormatCode($numberFormat['formatCode']);
+            /** @var string[] $numberFormat */
+            $objStyle->getNumberFormat()
+                ->setFormatCode($numberFormat['formatCode']);
 
             // offset:  4; size: 2; XF type, cell protection, and parent style XF
             // bit 2-0; mask 0x0007; XF_TYPE_PROT
@@ -1632,7 +1685,7 @@ class Xls extends XlsBase
             $string = $this->readByteStringShort(substr($recordData, 6));
             $rec_name = $string['value'];
         }
-
+        /** @var string $rec_name */
         $this->sheets[] = [
             'name' => $rec_name,
             'offset' => $rec_offset,
@@ -1837,6 +1890,7 @@ class Xls extends XlsBase
 
         // get spliced record data
         $splicedRecordData = $this->getSplicedRecordData();
+        /** @var string */
         $recordData = $splicedRecordData['recordData'];
 
         $this->drawingGroupData .= $recordData;
@@ -1865,12 +1919,14 @@ class Xls extends XlsBase
         $splicedRecordData = $this->getSplicedRecordData();
 
         $recordData = $splicedRecordData['recordData'];
+        /** @var mixed[] */
         $spliceOffsets = $splicedRecordData['spliceOffsets'];
 
         // offset: 0; size: 4; total number of strings in the workbook
         $pos += 4;
 
         // offset: 4; size: 4; number of following strings ($nm)
+        /** @var string $recordData */
         $nm = self::getInt4d($recordData, 4);
         $pos += 4;
 
@@ -1886,10 +1942,13 @@ class Xls extends XlsBase
         // loop through the Unicode strings (16-bit length)
         for ($i = 0; $i < $nm && $pos < $limitposSST; ++$i) {
             // number of characters in the Unicode string
+            /** @var int $pos */
             $numChars = self::getUInt2d($recordData, $pos);
+            /** @var int $pos */
             $pos += 2;
 
             // option flags
+            /** @var string $recordData */
             $optionFlags = ord($recordData[$pos]);
             ++$pos;
 
@@ -1931,6 +1990,7 @@ class Xls extends XlsBase
                 }
             }
 
+            /** @var int $limitpos */
             if ($pos + $len <= $limitpos) {
                 // character array is not split between records
 
@@ -1963,11 +2023,14 @@ class Xls extends XlsBase
                     // repeated option flags
                     // OpenOffice.org documentation 5.21
                     $option = ord($recordData[$pos]);
+                    /** @var int $pos */
                     ++$pos;
 
+                    /** @var int $limitpos */
                     if ($isCompressed && ($option == 0)) {
                         // 1st fragment compressed
                         // this fragment compressed
+                        /** @var int */
                         $len = min($charsLeft, $limitpos - $pos);
                         $retstr .= substr($recordData, $pos, $len);
                         $charsLeft -= $len;
@@ -1975,6 +2038,7 @@ class Xls extends XlsBase
                     } elseif (!$isCompressed && ($option != 0)) {
                         // 1st fragment uncompressed
                         // this fragment uncompressed
+                        /** @var int */
                         $len = min($charsLeft * 2, $limitpos - $pos);
                         $retstr .= substr($recordData, $pos, $len);
                         $charsLeft -= $len / 2;
@@ -1998,6 +2062,7 @@ class Xls extends XlsBase
                             $newstr .= $retstr[$j] . chr(0);
                         }
                         $retstr = $newstr;
+                        /** @var int */
                         $len = min($charsLeft * 2, $limitpos - $pos);
                         $retstr .= substr($recordData, $pos, $len);
                         $charsLeft -= $len / 2;
@@ -2017,6 +2082,7 @@ class Xls extends XlsBase
                 // list of formatting runs
                 for ($j = 0; $j < $formattingRuns; ++$j) {
                     // first formatted character; zero-based
+                    /** @var int $pos */
                     $charPos = self::getUInt2d($recordData, $pos + $j * 4);
 
                     // index to font record
@@ -2182,8 +2248,13 @@ class Xls extends XlsBase
                     $string = $this->readByteStringShort($recordData);
                 }
 
-                $this->phpSheet->getHeaderFooter()->setOddHeader($string['value']);
-                $this->phpSheet->getHeaderFooter()->setEvenHeader($string['value']);
+                /** @var string[] $string */
+                $this->phpSheet
+                    ->getHeaderFooter()
+                    ->setOddHeader($string['value']);
+                $this->phpSheet
+                    ->getHeaderFooter()
+                    ->setEvenHeader($string['value']);
             }
         }
     }
@@ -2208,8 +2279,14 @@ class Xls extends XlsBase
                 } else {
                     $string = $this->readByteStringShort($recordData);
                 }
-                $this->phpSheet->getHeaderFooter()->setOddFooter($string['value']);
-                $this->phpSheet->getHeaderFooter()->setEvenFooter($string['value']);
+                /** @var string */
+                $temp = $string['value'];
+                $this->phpSheet
+                    ->getHeaderFooter()
+                    ->setOddFooter($temp);
+                $this->phpSheet
+                    ->getHeaderFooter()
+                    ->setEvenFooter($temp);
             }
         }
     }
@@ -2689,9 +2766,14 @@ class Xls extends XlsBase
                 $charPos = 0;
                 $sstCount = count($this->sst[$index]['fmtRuns']);
                 for ($i = 0; $i <= $sstCount; ++$i) {
+                    /** @var mixed[][] $fmtRuns */
                     if (isset($fmtRuns[$i])) {
-                        $text = StringHelper::substring($this->sst[$index]['value'], $charPos, $fmtRuns[$i]['charPos'] - $charPos);
-                        $charPos = $fmtRuns[$i]['charPos'];
+                        /** @var int[] */
+                        $temp = $fmtRuns[$i];
+                        $temp = $temp['charPos'];
+                        /** @var int $charPos */
+                        $text = StringHelper::substring($this->sst[$index]['value'], $charPos, $temp - $charPos);
+                        $charPos = $temp;
                     } else {
                         $text = StringHelper::substring($this->sst[$index]['value'], $charPos, StringHelper::countCharacters($this->sst[$index]['value']));
                     }
@@ -2701,13 +2783,16 @@ class Xls extends XlsBase
                             $richText->createText($text);
                         } else {
                             $textRun = $richText->createTextRun($text);
+                            /** @var int[][] $fmtRuns */
                             if (isset($fmtRuns[$i - 1])) {
                                 if ($fmtRuns[$i - 1]['fontIndex'] < 4) {
                                     $fontIndex = $fmtRuns[$i - 1]['fontIndex'];
                                 } else {
                                     // this has to do with that index 4 is omitted in all BIFF versions for some stra          nge reason
                                     // check the OpenOffice documentation of the FONT record
-                                    $fontIndex = $fmtRuns[$i - 1]['fontIndex'] - 1;
+                                    /** @var int */
+                                    $temp = $fmtRuns[$i - 1]['fontIndex'];
+                                    $fontIndex = $temp - 1;
                                 }
                                 if (array_key_exists($fontIndex, $this->objFonts) === false) {
                                     $fontIndex = count($this->objFonts) - 1;
@@ -3015,6 +3100,7 @@ class Xls extends XlsBase
             $string = $this->readByteStringLong($recordData);
             $value = $string['value'];
         }
+        /** @var string $value */
 
         return $value;
     }
@@ -3158,6 +3244,7 @@ class Xls extends XlsBase
                 $string = $this->readByteStringLong(substr($recordData, 6));
                 $value = $string['value'];
             }
+            /** @var string $value */
             if ($this->readEmptyCells || trim($value) !== '') {
                 $cell = $this->phpSheet->getCell($columnString . ($row + 1));
                 $cell->setValueExplicit($value, DataType::TYPE_STRING);
@@ -3211,7 +3298,7 @@ class Xls extends XlsBase
         $splicedRecordData = $this->getSplicedRecordData();
         $recordData = $splicedRecordData['recordData'];
 
-        $this->drawingData .= $recordData;
+        $this->drawingData .= StringHelper::convertToString($recordData);
     }
 
     /**
@@ -3491,6 +3578,7 @@ class Xls extends XlsBase
         ++$rangeBoundaries[1][0];
         for ($row = $rangeBoundaries[0][1]; $row <= $rangeBoundaries[1][1]; ++$row) {
             for ($column = $rangeBoundaries[0][0]; $column != $rangeBoundaries[1][0]; ++$column) {
+                /** @var string $column */
                 if ($this->getReadFilter()->readCell($column, $row, $this->phpSheet->getTitle())) {
                     $includeCellRange = true;
 
@@ -3522,6 +3610,7 @@ class Xls extends XlsBase
         if ($this->version == self::XLS_BIFF8 && !$this->readDataOnly) {
             $cellRangeAddressList = Xls\Biff8::readBIFF8CellRangeAddressList($recordData);
             foreach ($cellRangeAddressList['cellRangeAddresses'] as $cellRangeAddress) {
+                /** @var string $cellRangeAddress */
                 if (
                     (str_contains($cellRangeAddress, ':'))
                     && ($this->includeCellRangeFiltered($cellRangeAddress))
@@ -3750,6 +3839,7 @@ class Xls extends XlsBase
                 case 0x14:
                     // offset: 16; size: 2; color index for sheet tab
                     $colorIndex = self::getUInt2d($recordData, 16);
+                    /** @var string[] */
                     $color = Xls\Color::map($colorIndex, $this->palette, $this->version);
                     $this->phpSheet->getTabColor()->setRGB($color['rgb']);
 
@@ -3964,7 +4054,7 @@ class Xls extends XlsBase
         if (in_array($splitPoint, $validSplitPoints)) {
             // get spliced record data (and move pointer to next record)
             $splicedRecordData = $this->getSplicedRecordData();
-            $this->drawingData .= $splicedRecordData['recordData'];
+            $this->drawingData .= StringHelper::convertToString($splicedRecordData['recordData']);
 
             return;
         }
@@ -3978,6 +4068,8 @@ class Xls extends XlsBase
      * records are found. Splices the record data pieces and returns the combined string as if record data
      * is in one piece.
      * Moves to next current position in data stream to start of next record different from a CONtINUE record.
+     *
+     * @return mixed[]
      */
     private function getSplicedRecordData(): array
     {
@@ -4050,6 +4142,7 @@ class Xls extends XlsBase
 
         while ($formulaData !== '' && $token = $this->getNextToken($formulaData, $baseCell)) {
             $tokens[] = $token;
+            /** @var int[] $token */
             $formulaData = substr($formulaData, $token['size']);
         }
 
@@ -4061,6 +4154,7 @@ class Xls extends XlsBase
     /**
      * Take array of tokens together with additional data for formula and return human readable formula.
      *
+     * @param mixed[][] $tokens
      * @param string $additionalData Additional binary data going with the formula
      *
      * @return string Human readable formula
@@ -4081,7 +4175,8 @@ class Xls extends XlsBase
             $space3 = $space3 ?? ''; // carriage returns before opening parenthesis
             $space4 = $space4 ?? ''; // spaces before closing parenthesis
             $space5 = $space5 ?? ''; // carriage returns before closing parenthesis
-
+            /** @var string */
+            $tokenData = $token['data'] ?? '';
             switch ($token['name']) {
                 case 'tAdd': // addition
                 case 'tConcat': // addition
@@ -4100,20 +4195,20 @@ class Xls extends XlsBase
                 case 'tSub': // subtraction
                     $op2 = array_pop($formulaStrings);
                     $op1 = array_pop($formulaStrings);
-                    $formulaStrings[] = "$op1$space1$space0{$token['data']}$op2";
+                    $formulaStrings[] = "$op1$space1$space0{$tokenData}$op2";
                     unset($space0, $space1);
 
                     break;
                 case 'tUplus': // unary plus
                 case 'tUminus': // unary minus
                     $op = array_pop($formulaStrings);
-                    $formulaStrings[] = "$space1$space0{$token['data']}$op";
+                    $formulaStrings[] = "$space1$space0{$tokenData}$op";
                     unset($space0, $space1);
 
                     break;
                 case 'tPercent': // percent sign
                     $op = array_pop($formulaStrings);
-                    $formulaStrings[] = "$op$space1$space0{$token['data']}";
+                    $formulaStrings[] = "$op$space1$space0{$tokenData}";
                     unset($space0, $space1);
 
                     break;
@@ -4126,29 +4221,30 @@ class Xls extends XlsBase
                     break;
                 case 'tAttrSpace': // space / carriage return
                     // space will be used when next token arrives, do not alter formulaString stack
+                    /** @var string[][] $token */
                     switch ($token['data']['spacetype']) {
                         case 'type0':
-                            $space0 = str_repeat(' ', $token['data']['spacecount']);
+                            $space0 = str_repeat(' ', (int) $token['data']['spacecount']);
 
                             break;
                         case 'type1':
-                            $space1 = str_repeat("\n", $token['data']['spacecount']);
+                            $space1 = str_repeat("\n", (int) $token['data']['spacecount']);
 
                             break;
                         case 'type2':
-                            $space2 = str_repeat(' ', $token['data']['spacecount']);
+                            $space2 = str_repeat(' ', (int) $token['data']['spacecount']);
 
                             break;
                         case 'type3':
-                            $space3 = str_repeat("\n", $token['data']['spacecount']);
+                            $space3 = str_repeat("\n", (int) $token['data']['spacecount']);
 
                             break;
                         case 'type4':
-                            $space4 = str_repeat(' ', $token['data']['spacecount']);
+                            $space4 = str_repeat(' ', (int) $token['data']['spacecount']);
 
                             break;
                         case 'type5':
-                            $space5 = str_repeat("\n", $token['data']['spacecount']);
+                            $space5 = str_repeat("\n", (int) $token['data']['spacecount']);
 
                             break;
                     }
@@ -4162,19 +4258,25 @@ class Xls extends XlsBase
                     break;
                 case 'tFunc': // function with fixed number of arguments
                 case 'tFuncV': // function with variable number of arguments
-                    if ($token['data']['function'] != '') {
+                    /** @var string[] */
+                    $temp1 = $token['data'];
+                    $temp2 = $temp1['function'];
+                    if ($temp2 != '') {
                         // normal function
                         $ops = []; // array of operators
-                        for ($i = 0; $i < $token['data']['args']; ++$i) {
+                        $temp3 = (int) $temp1['args'];
+                        for ($i = 0; $i < $temp3; ++$i) {
                             $ops[] = array_pop($formulaStrings);
                         }
                         $ops = array_reverse($ops);
-                        $formulaStrings[] = "$space1$space0{$token['data']['function']}(" . implode(',', $ops) . ')';
+                        $formulaStrings[] = "$space1$space0{$temp2}(" . implode(',', $ops) . ')';
                         unset($space0, $space1);
                     } else {
                         // add-in function
                         $ops = []; // array of operators
-                        for ($i = 0; $i < $token['data']['args'] - 1; ++$i) {
+                        /** @var int[] */
+                        $temp = $token['data'];
+                        for ($i = 0; $i < $temp['args'] - 1; ++$i) {
                             $ops[] = array_pop($formulaStrings);
                         }
                         $ops = array_reverse($ops);
@@ -4201,7 +4303,7 @@ class Xls extends XlsBase
                     // bite off chunk of additional data
                     $cellRangeAddressList = Xls\Biff8::readBIFF8CellRangeAddressList($additionalData);
                     $additionalData = substr($additionalData, $cellRangeAddressList['size']);
-                    $formulaStrings[] = "$space1$space0{$token['data']}";
+                    $formulaStrings[] = "$space1$space0{$tokenData}";
                     unset($space0, $space1);
 
                     break;
@@ -4221,7 +4323,7 @@ class Xls extends XlsBase
                 case 'tRefN':
                 case 'tAreaN':
                 case 'tStr': // string
-                    $formulaStrings[] = "$space1$space0{$token['data']}";
+                    $formulaStrings[] = "$space1$space0{$tokenData}";
                     unset($space0, $space1);
 
                     break;
@@ -4237,6 +4339,8 @@ class Xls extends XlsBase
      *
      * @param string $formulaData Formula data
      * @param string $baseCell Base cell, only needed when formula contains tRefN tokens, e.g. with shared formulas
+     *
+     * @return mixed[]
      */
     private function getNextToken(string $formulaData, string $baseCell = 'A1'): array
     {
@@ -4510,7 +4614,8 @@ class Xls extends XlsBase
                 // offset: 1; size: 2; one-based index to definedname record
                 $definedNameIndex = self::getUInt2d($formulaData, 1) - 1;
                 // offset: 2; size: 2; not used
-                $data = $this->definedname[$definedNameIndex]['name'] ?? '';
+                /** @var string[] */
+                $data = $this->definedname[$definedNameIndex]['name'] ?? ''; //* @phpstan-ignore-line
 
                 break;
             case 0x24:    //    single cell reference e.g. A5
@@ -4694,6 +4799,8 @@ class Xls extends XlsBase
     /**
      * Read byte string (8-bit string length)
      * OpenOffice documentation: 2.5.2.
+     *
+     * @return array{value: mixed, size: int}
      */
     protected function readByteStringShort(string $subData): array
     {
@@ -4712,6 +4819,8 @@ class Xls extends XlsBase
     /**
      * Read byte string (16-bit string length)
      * OpenOffice documentation: 2.5.2.
+     *
+     * @return array{value: mixed, size: int}
      */
     protected function readByteStringLong(string $subData): array
     {
@@ -4742,6 +4851,8 @@ class Xls extends XlsBase
      * For now, however, this function makes it readable,
      * which satisfies Phpstan.
      *
+     * @return mixed[]
+     *
      * @codeCoverageIgnore
      */
     public function getMapCellStyleXfIndex(): array
@@ -4753,12 +4864,15 @@ class Xls extends XlsBase
      * Parse conditional formatting blocks.
      *
      * @see https://www.openoffice.org/sc/excelfileformat.pdf Search for CFHEADER followed by CFRULE
+     *
+     * @return mixed[]
      */
     protected function readCFHeader(): array
     {
         return (new Xls\ConditionalFormatting())->readCFHeader2($this);
     }
 
+    /** @param string[] $cellRangeAddresses */
     protected function readCFRule(array $cellRangeAddresses): void
     {
         (new Xls\ConditionalFormatting())->readCFRule2($cellRangeAddresses, $this);
diff --git a/src/PhpSpreadsheet/Reader/Xls/Biff5.php b/src/PhpSpreadsheet/Reader/Xls/Biff5.php
index ef9619eec..61ff9ee0b 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Biff5.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Biff5.php
@@ -46,6 +46,8 @@ class Biff5 extends Xls
     /**
      * Read BIFF5 cell range address list
      * section 2.5.15.
+     *
+     * @return array{size: int, cellRangeAddresses: string[]}
      */
     public static function readBIFF5CellRangeAddressList(string $subData): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/Biff8.php b/src/PhpSpreadsheet/Reader/Xls/Biff8.php
index f95c0b5ea..2de9fb8c3 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Biff8.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Biff8.php
@@ -12,6 +12,8 @@ class Biff8 extends Xls
      * read BIFF8 constant value array from array data
      * returns e.g. ['value' => '{1,2;3,4}', 'size' => 40]
      * section 2.5.8.
+     *
+     * @return array{value: string, size: int}
      */
     protected static function readBIFF8ConstantArray(string $arrayData): array
     {
@@ -47,6 +49,8 @@ class Biff8 extends Xls
      * read BIFF8 constant value which may be 'Empty Value', 'Number', 'String Value', 'Boolean Value', 'Error Value'
      * section 2.5.7
      * returns e.g. ['value' => '5', 'size' => 9].
+     *
+     * @return array{value: bool|float|int|string, size: int}
      */
     private static function readBIFF8Constant(string $valueData): array
     {
@@ -101,6 +105,8 @@ class Biff8 extends Xls
     /**
      * Read BIFF8 cell range address list
      * section 2.5.15.
+     *
+     * @return array{size: int, cellRangeAddresses: mixed[]}
      */
     public static function readBIFF8CellRangeAddressList(string $subData): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/Color.php b/src/PhpSpreadsheet/Reader/Xls/Color.php
index 17b6e165c..adbe1a251 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Color.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Color.php
@@ -10,9 +10,9 @@ class Color
      * Read color.
      *
      * @param int $color Indexed color
-     * @param array $palette Color palette
+     * @param string[][] $palette Color palette
      *
-     * @return array RGB color value, example: ['rgb' => 'FF0000']
+     * @return string[] RGB color value, example: ['rgb' => 'FF0000']
      */
     public static function map(int $color, array $palette, int $version): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/Color/BIFF5.php b/src/PhpSpreadsheet/Reader/Xls/Color/BIFF5.php
index 2c0790c9c..ecc026c38 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Color/BIFF5.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Color/BIFF5.php
@@ -65,6 +65,8 @@ class BIFF5
 
     /**
      * Map color array from BIFF5 built-in color index.
+     *
+     * @return array{rgb: string}
      */
     public static function lookup(int $color): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/Color/BIFF8.php b/src/PhpSpreadsheet/Reader/Xls/Color/BIFF8.php
index 914034df2..11745f797 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Color/BIFF8.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Color/BIFF8.php
@@ -65,6 +65,8 @@ class BIFF8
 
     /**
      * Map color array from BIFF8 built-in color index.
+     *
+     * @return array{rgb: string}
      */
     public static function lookup(int $color): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/Color/BuiltIn.php b/src/PhpSpreadsheet/Reader/Xls/Color/BuiltIn.php
index a715b110b..575244645 100644
--- a/src/PhpSpreadsheet/Reader/Xls/Color/BuiltIn.php
+++ b/src/PhpSpreadsheet/Reader/Xls/Color/BuiltIn.php
@@ -21,6 +21,8 @@ class BuiltIn
      * Map built-in color to RGB value.
      *
      * @param int $color Indexed color
+     *
+     * @return array{rgb: string}
      */
     public static function lookup(int $color): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xls/ConditionalFormatting.php b/src/PhpSpreadsheet/Reader/Xls/ConditionalFormatting.php
index 1c05c63c7..9f89d1620 100644
--- a/src/PhpSpreadsheet/Reader/Xls/ConditionalFormatting.php
+++ b/src/PhpSpreadsheet/Reader/Xls/ConditionalFormatting.php
@@ -48,6 +48,8 @@ class ConditionalFormatting extends Xls
      * Parse conditional formatting blocks.
      *
      * @see https://www.openoffice.org/sc/excelfileformat.pdf Search for CFHEADER followed by CFRULE
+     *
+     * @return mixed[]
      */
     protected function readCFHeader2(Xls $xls): array
     {
@@ -73,6 +75,7 @@ class ConditionalFormatting extends Xls
         return $cellRangeAddresses;
     }
 
+    /** @param string[] $cellRangeAddresses */
     protected function readCFRule2(array $cellRangeAddresses, Xls $xls): void
     {
         $length = self::getUInt2d($xls->data, $xls->pos + 2);
@@ -212,7 +215,9 @@ class ConditionalFormatting extends Xls
         $color = self::getInt4d($options, 80);
 
         if ($color !== -1) {
-            $style->getFont()->getColor()->setRGB(Color::map($color, $xls->palette, $xls->version)['rgb']);
+            $style->getFont()
+                ->getColor()
+                ->setRGB(Color::map($color, $xls->palette, $xls->version)['rgb']);
         }
     }
 
@@ -222,6 +227,7 @@ class ConditionalFormatting extends Xls
 
     private function getCFBorderStyle(string $options, Style $style, bool $hasBorderLeft, bool $hasBorderRight, bool $hasBorderTop, bool $hasBorderBottom, Xls $xls): void
     {
+        /** @var false|int[] */
         $valueArray = unpack('V', $options);
         $value = is_array($valueArray) ? $valueArray[1] : 0;
         $left = $value & 15;
@@ -230,6 +236,7 @@ class ConditionalFormatting extends Xls
         $bottom = ($value >> 12) & 15;
         $leftc = ($value >> 16) & 0x7F;
         $rightc = ($value >> 23) & 0x7F;
+        /** @var false|int[] */
         $valueArray = unpack('V', substr($options, 4));
         $value = is_array($valueArray) ? $valueArray[1] : 0;
         $topc = $value & 0x7F;
@@ -308,6 +315,7 @@ class ConditionalFormatting extends Xls
         }
     }
 
+    /** @param string[] $cellRanges */
     private function setCFRules(array $cellRanges, string $type, string $operator, null|float|int|string $formula1, null|float|int|string $formula2, Style $style, bool $noFormatSet, Xls $xls): void
     {
         foreach ($cellRanges as $cellRange) {
@@ -324,10 +332,14 @@ class ConditionalFormatting extends Xls
             }
             $conditional->setStyle($style);
 
-            $conditionalStyles = $xls->phpSheet->getStyle($cellRange)->getConditionalStyles();
+            $conditionalStyles = $xls->phpSheet
+                ->getStyle($cellRange)
+                ->getConditionalStyles();
             $conditionalStyles[] = $conditional;
 
-            $xls->phpSheet->getStyle($cellRange)->setConditionalStyles($conditionalStyles);
+            $xls->phpSheet
+                ->getStyle($cellRange)
+                ->setConditionalStyles($conditionalStyles);
         }
     }
 }
diff --git a/src/PhpSpreadsheet/Reader/Xls/DataValidationHelper.php b/src/PhpSpreadsheet/Reader/Xls/DataValidationHelper.php
index e3a8d98c1..b5a945444 100644
--- a/src/PhpSpreadsheet/Reader/Xls/DataValidationHelper.php
+++ b/src/PhpSpreadsheet/Reader/Xls/DataValidationHelper.php
@@ -176,6 +176,7 @@ class DataValidationHelper extends Xls
 
         // offset: var; size: var; cell range address list with
         $cellRangeAddressList = Biff8::readBIFF8CellRangeAddressList(substr($recordData, $offset));
+        /** @var string[] */
         $cellRangeAddresses = $cellRangeAddressList['cellRangeAddresses'];
         $maxRow = (string) AddressRange::MAX_ROW;
         $maxCol = AddressRange::MAX_COLUMN;
diff --git a/src/PhpSpreadsheet/Reader/Xls/ListFunctions.php b/src/PhpSpreadsheet/Reader/Xls/ListFunctions.php
index 9d3eeaba7..cd1c5cae9 100644
--- a/src/PhpSpreadsheet/Reader/Xls/ListFunctions.php
+++ b/src/PhpSpreadsheet/Reader/Xls/ListFunctions.php
@@ -48,7 +48,7 @@ class ListFunctions extends Xls
         }
 
         foreach ($xls->sheets as $sheet) {
-            if ($sheet['sheetType'] === 0x00 && is_string($sheet['name'])) {
+            if ($sheet['sheetType'] === 0x00) {
                 // 0x00: Worksheet, 0x02: Chart, 0x06: Visual Basic module
                 $worksheetNames[] = $sheet['name'];
             }
diff --git a/src/PhpSpreadsheet/Reader/Xls/LoadSpreadsheet.php b/src/PhpSpreadsheet/Reader/Xls/LoadSpreadsheet.php
index cf99d472c..60fc5a125 100644
--- a/src/PhpSpreadsheet/Reader/Xls/LoadSpreadsheet.php
+++ b/src/PhpSpreadsheet/Reader/Xls/LoadSpreadsheet.php
@@ -52,7 +52,7 @@ class LoadSpreadsheet extends Xls
         $xls->sheets = [];
         $xls->externalBooks = [];
         $xls->ref = [];
-        $xls->definedname = [];
+        $xls->definedname = []; //* @phpstan-ignore-line
         $xls->sst = [];
         $xls->drawingGroupData = '';
         $xls->xfIndex = 0;
@@ -382,6 +382,7 @@ class LoadSpreadsheet extends Xls
 
                         break;
                     case self::XLS_TYPE_CFHEADER:
+                        /** @var string[] */
                         $cellRangeAddresses = $xls->readCFHeader();
 
                         break;
@@ -464,6 +465,7 @@ class LoadSpreadsheet extends Xls
                     $offsetX = (int) ($startOffsetX * SharedXls::sizeCol($xls->phpSheet, $startColumn) / 1024);
                     $offsetY = (int) ($startOffsetY * SharedXls::sizeRow($xls->phpSheet, $startRow) / 256);
 
+                    /** @var int[] $obj */
                     switch ($obj['otObjType']) {
                         case 0x19:
                             // Note
@@ -472,7 +474,7 @@ class LoadSpreadsheet extends Xls
 
                                 if (isset($xls->textObjects[$obj['idObjID']])) {
                                     $textObject = $xls->textObjects[$obj['idObjID']];
-                                    $xls->cellNotes[$obj['idObjID']]['objTextData'] = $textObject;
+                                    $xls->cellNotes[$obj['idObjID']]['objTextData'] = $textObject; //* @phpstan-ignore-line
                                 }
                             }
 
@@ -492,6 +494,7 @@ class LoadSpreadsheet extends Xls
                             }
 
                             if ($escherWorkbook) {
+                                /** @var BSE[] */
                                 $BSECollection = method_exists($escherWorkbook, 'getDggContainer') ? $escherWorkbook->getDggContainer()->getBstoreContainer()->getBSECollection() : [];
                                 $BSE = $BSECollection[$BSEindex - 1];
                                 $blipType = $BSE->getBlipType();
@@ -545,7 +548,9 @@ class LoadSpreadsheet extends Xls
                     /** @var int $row */
                     [$column, $row] = Coordinate::coordinateFromString($cell);
                     if ($xls->getReadFilter()->readCell($column, $row, $xls->phpSheet->getTitle())) {
-                        $formula = $xls->getFormulaFromStructure($xls->sharedFormulas[$baseCell], $cell);
+                        /** @var string */
+                        $temp = $xls->sharedFormulas[$baseCell];
+                        $formula = $xls->getFormulaFromStructure($temp, $cell);
                         $xls->phpSheet->getCell($cell)->setValueExplicit('=' . $formula, DataType::TYPE_FORMULA);
                     }
                 }
@@ -553,6 +558,7 @@ class LoadSpreadsheet extends Xls
 
             if (!empty($xls->cellNotes)) {
                 foreach ($xls->cellNotes as $note => $noteDetails) {
+                    /** @var array{author: string, cellRef: string, objTextData?: mixed[]} $noteDetails */
                     if (!isset($noteDetails['objTextData'])) {
                         if (isset($xls->textObjects[$note])) {
                             $textObject = $xls->textObjects[$note];
@@ -562,7 +568,14 @@ class LoadSpreadsheet extends Xls
                         }
                     }
                     $cellAddress = str_replace('$', '', $noteDetails['cellRef']);
-                    $xls->phpSheet->getComment($cellAddress)->setAuthor($noteDetails['author'])->setText($xls->parseRichText($noteDetails['objTextData']['text']));
+                    /** @var string */
+                    $tempDetails = $noteDetails['objTextData']['text'];
+                    $xls->phpSheet
+                        ->getComment($cellAddress)
+                        ->setAuthor($noteDetails['author'])
+                        ->setText(
+                            $xls->parseRichText($tempDetails)
+                        );
                 }
             }
             if ($selectedCells !== '') {
@@ -575,6 +588,7 @@ class LoadSpreadsheet extends Xls
 
         // add the named ranges (defined names)
         foreach ($xls->definedname as $definedName) {
+            /** @var array{isBuiltInName: int, name: string, formula: string, scope: int} $definedName */
             if ($definedName['isBuiltInName']) {
                 switch ($definedName['name']) {
                     case pack('C', 0x06):
@@ -647,7 +661,6 @@ class LoadSpreadsheet extends Xls
                 }
             } else {
                 // Extract range
-                /** @var non-empty-string $formula */
                 $formula = $definedName['formula'];
                 if (str_contains($formula, '!')) {
                     $explodes = Worksheet::extractSheetTitle($formula, true, true);
diff --git a/src/PhpSpreadsheet/Reader/Xls/MD5.php b/src/PhpSpreadsheet/Reader/Xls/MD5.php
index 7da2eeee5..56dd4a322 100644
--- a/src/PhpSpreadsheet/Reader/Xls/MD5.php
+++ b/src/PhpSpreadsheet/Reader/Xls/MD5.php
@@ -2,6 +2,8 @@
 
 namespace PhpOffice\PhpSpreadsheet\Reader\Xls;
 
+use PhpOffice\PhpSpreadsheet\Reader\Exception as ReaderException;
+
 class MD5
 {
     private int $a;
@@ -58,8 +60,9 @@ class MD5
      */
     public function add(string $data): void
     {
-        // @phpstan-ignore-next-line
-        $words = array_values(unpack('V16', $data));
+        $unpacked = unpack('V16', $data) ?: throw new ReaderException('unable to unpack data');
+        /** @var int[] */
+        $words = array_values($unpacked);
 
         $A = $this->a;
         $B = $this->b;
@@ -173,7 +176,9 @@ class MD5
     private static function step(callable $func, int &$A, int $B, int $C, int $D, int $M, int $s, $t): void
     {
         $t = self::signedInt($t);
-        $A = (int) ($A + call_user_func($func, $B, $C, $D) + $M + $t) & self::$allOneBits;
+        /** @var int */
+        $temp = call_user_func($func, $B, $C, $D);
+        $A = (int) ($A + $temp + $M + $t) & self::$allOneBits;
         $A = self::rotate($A, $s);
         $A = (int) ($B + $A) & self::$allOneBits;
     }
diff --git a/src/PhpSpreadsheet/Reader/XlsBase.php b/src/PhpSpreadsheet/Reader/XlsBase.php
index e6969db04..6f9da57ce 100644
--- a/src/PhpSpreadsheet/Reader/XlsBase.php
+++ b/src/PhpSpreadsheet/Reader/XlsBase.php
@@ -177,6 +177,8 @@ class XlsBase extends BaseReader
      * OpenOffice.org's Documentation of the Microsoft Excel File Format, section 2.5.4.
      *
      * @param string $rgb Encoded RGB value (4 bytes)
+     *
+     * @return array{rgb: string}
      */
     protected static function readRGB(string $rgb): array
     {
@@ -199,6 +201,8 @@ class XlsBase extends BaseReader
      * Extracts an Excel Unicode short string (8-bit string length)
      * OpenOffice documentation: 2.5.3
      * function will automatically find out where the Unicode string ends.
+     *
+     * @return array{value: string, size: int}
      */
     protected static function readUnicodeStringShort(string $subData): array
     {
@@ -217,6 +221,8 @@ class XlsBase extends BaseReader
      * Extracts an Excel Unicode long string (16-bit string length)
      * OpenOffice documentation: 2.5.3
      * this function is under construction, needs to support rich text, and Asian phonetic settings.
+     *
+     * @return array{value: string, size: int}
      */
     protected static function readUnicodeStringLong(string $subData): array
     {
@@ -235,6 +241,8 @@ class XlsBase extends BaseReader
      * Read Unicode string with no string length field, but with known character count
      * this function is under construction, needs to support rich text, and Asian phonetic settings
      * OpenOffice.org's Documentation of the Microsoft Excel File Format, section 2.5.3.
+     *
+     * @return array{value: string, size: int}
      */
     protected static function readUnicodeString(string $subData, int $characterCount): array
     {
diff --git a/src/PhpSpreadsheet/Reader/Xlsx.php b/src/PhpSpreadsheet/Reader/Xlsx.php
index e687e4a2f..178f73bcc 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx.php
@@ -38,6 +38,7 @@ use PhpOffice\PhpSpreadsheet\Style\Font as StyleFont;
 use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
 use PhpOffice\PhpSpreadsheet\Style\Style;
 use PhpOffice\PhpSpreadsheet\Worksheet\HeaderFooterDrawing;
+use PhpOffice\PhpSpreadsheet\Worksheet\Table\TableDxfsStyle;
 use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 use SimpleXMLElement;
 use Throwable;
@@ -57,6 +58,7 @@ class Xlsx extends BaseReader
 
     private Styles $styleReader;
 
+    /** @var SharedFormula[] */
     private array $sharedFormulae = [];
 
     /**
@@ -102,11 +104,13 @@ class Xlsx extends BaseReader
     }
 
     // Phpstan thinks, correctly, that xpath can return false.
+    /** @return mixed[] */
     private static function xpathNoFalse(SimpleXMLElement $sxml, string $path): array
     {
         return self::falseToArray($sxml->xpath($path));
     }
 
+    /** @return mixed[] */
     public static function falseToArray(mixed $value): array
     {
         return is_array($value) ? $value : [];
@@ -158,6 +162,8 @@ class Xlsx extends BaseReader
 
     /**
      * Reads names of the worksheets from a file, without parsing the whole file to a Spreadsheet object.
+     *
+     * @return string[]
      */
     public function listWorksheetNames(string $filename): array
     {
@@ -408,6 +414,7 @@ class Xlsx extends BaseReader
         $addingFirstCellStyleXf = true;
         $addingFirstCellXf = true;
 
+        /** @var mixed[][][][] */
         $unparsedLoadedData = [];
 
         $this->zip = $zip = new ZipArchive();
@@ -602,11 +609,13 @@ class Xlsx extends BaseReader
                         $numFmts = $xmlStyles->numFmts[0];
                     }
                     if (isset($numFmts)) {
+                        /** @var SimpleXMLElement $numFmts */
                         $numFmts->registerXPathNamespace('sml', $mainNS);
                     }
                     $this->styleReader->setNamespace($mainNS);
                     if (!$this->readDataOnly/* && $xmlStyles*/) {
                         foreach ($xfTags as $xfTag) {
+                            /** @var SimpleXMLElement $xfTag */
                             $xf = self::getAttributes($xfTag);
                             $numFmt = null;
 
@@ -655,6 +664,7 @@ class Xlsx extends BaseReader
                         }
 
                         foreach ($cellXfTags as $xfTag) {
+                            /** @var SimpleXMLElement $xfTag */
                             $xf = self::getAttributes($xfTag);
                             $numFmt = NumberFormat::FORMAT_GENERAL;
                             if ($numFmts && $xf['numFmtId']) {
@@ -803,6 +813,7 @@ class Xlsx extends BaseReader
                                 $xmlSheetMain = $xmlSheetNS->children($mainNS);
                                 // Setting Conditional Styles adjusts selected cells, so we need to execute this
                                 //    before reading the sheet view data to get the actual selected cells
+                                /** @var Style[] $dxfs */
                                 if (!$this->readDataOnly && ($xmlSheet->conditionalFormatting)) {
                                     (new ConditionalStyles($docSheet, $xmlSheet, $dxfs, $this->styleReader))->load();
                                 }
@@ -967,7 +978,7 @@ class Xlsx extends BaseReader
                                                 $cAttrS = isset($styles[$cAttrS]) ? $cAttrS : 0;
                                                 $cell->setXfIndex($cAttrS);
                                                 // issue 3495
-                                                if ($cellDataType === DataType::TYPE_FORMULA && $styles[$cAttrS]->quotePrefix === true) {
+                                                if ($cellDataType === DataType::TYPE_FORMULA && $styles[$cAttrS]->quotePrefix === true) { //* @phpstan-ignore-line
                                                     $holdSelected = $docSheet->getSelectedCells();
                                                     $cell->getStyle()->setQuotePrefix(false);
                                                     $docSheet->setSelectedCells($holdSelected);
@@ -1059,6 +1070,7 @@ class Xlsx extends BaseReader
                                 if ($mc->AlternateContent) {
                                     foreach ($mc->AlternateContent as $alternateContent) {
                                         $alternateContent = self::testSimpleXml($alternateContent);
+                                        /** @var mixed[][][][] $unparsedLoadedData */
                                         $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['AlternateContents'][] = $alternateContent->asXML();
                                     }
                                 }
@@ -1111,18 +1123,23 @@ class Xlsx extends BaseReader
                                     $commentsFile->registerXpathNamespace('com', $mainNS);
                                     $authorPath = self::xpathNoFalse($commentsFile, 'com:authors/com:author');
                                     foreach ($authorPath as $author) {
+                                        /** @var SimpleXMLElement $author */
                                         $authors[] = (string) $author;
                                     }
 
                                     // Loop through contents
                                     $contentPath = self::xpathNoFalse($commentsFile, 'com:commentList/com:comment');
                                     foreach ($contentPath as $comment) {
+                                        /** @var SimpleXMLElement $comment */
                                         $commentx = $comment->attributes();
+                                        /** @var array{ref: scalar, authorId?: scalar}  $commentx */
                                         $commentModel = $docSheet->getComment((string) $commentx['ref']);
                                         if (isset($commentx['authorId'])) {
                                             $commentModel->setAuthor($authors[(int) $commentx['authorId']]);
                                         }
-                                        $commentModel->setText($this->parseRichText($comment->children($mainNS)->text));
+                                        /** @var SimpleXMLElement */
+                                        $temp = $comment->children($mainNS);
+                                        $commentModel->setText($this->parseRichText($temp->text));
                                     }
                                 }
 
@@ -1160,6 +1177,7 @@ class Xlsx extends BaseReader
 
                                     $shapes = self::xpathNoFalse($vmlCommentsFile, '//v:shape');
                                     foreach ($shapes as $shape) {
+                                        /** @var SimpleXMLElement $shape */
                                         $shape->registerXPathNamespace('v', Namespaces::URN_VML);
 
                                         if (isset($shape['style'])) {
@@ -1276,7 +1294,9 @@ class Xlsx extends BaseReader
                                 // unparsed vmlDrawing
                                 if ($unparsedVmlDrawings) {
                                     foreach ($unparsedVmlDrawings as $rId => $relPath) {
+                                        /** @var mixed[][][] $unparsedLoadedData */
                                         $rId = substr($rId, 3); // rIdXXX
+                                        /** @var mixed[][] */
                                         $unparsedVmlDrawing = &$unparsedLoadedData['sheets'][$docSheet->getCodeName()]['vmlDrawings'];
                                         $unparsedVmlDrawing[$rId] = [];
                                         $unparsedVmlDrawing[$rId]['filePath'] = self::dirAdd("$dir/$fileWorksheet", $relPath);
@@ -1324,6 +1344,7 @@ class Xlsx extends BaseReader
 
                                             $shapes = self::xpathNoFalse($vmlDrawing, '//v:shape');
                                             foreach ($shapes as $idx => $shape) {
+                                                /** @var SimpleXMLElement $shape */
                                                 $shape->registerXPathNamespace('v', Namespaces::URN_VML);
                                                 $imageData = $shape->xpath('//v:imagedata');
 
@@ -1334,6 +1355,7 @@ class Xlsx extends BaseReader
                                                 $imageData = $imageData[$idx];
 
                                                 $imageData = self::getAttributes($imageData, Namespaces::URN_MSOFFICE);
+                                                /** @var array{width: int, height: int, margin-left?: int, margin-top: int} */
                                                 $style = self::toCSSArray((string) $shape['style']);
 
                                                 if (array_key_exists((string) $imageData['relid'], $drawings)) {
@@ -1668,6 +1690,7 @@ class Xlsx extends BaseReader
                                     }
 
                                     // store original rId of drawing files
+                                    /** @var mixed[][][][] $unparsedLoadedData */
                                     $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['drawingOriginalIds'] = [];
                                     foreach ($relsWorksheet->Relationship as $elex) {
                                         $ele = self::getAttributes($elex);
@@ -1696,12 +1719,14 @@ class Xlsx extends BaseReader
                                     if ($xmlAltDrawing->AlternateContent) {
                                         foreach ($xmlAltDrawing->AlternateContent as $alternateContent) {
                                             $alternateContent = self::testSimpleXml($alternateContent);
+                                            /** @var mixed[][][][][] $unparsedLoadedData */
                                             $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['drawingAlternateContents'][] = $alternateContent->asXML();
                                         }
                                     }
                                 }
                             }
 
+                            /** @var mixed[][][][] $unparsedLoadedData */
                             $this->readFormControlProperties($excel, $dir, $fileWorksheet, $docSheet, $unparsedLoadedData);
                             $this->readPrinterSettings($excel, $dir, $fileWorksheet, $docSheet, $unparsedLoadedData);
 
@@ -2044,11 +2069,13 @@ class Xlsx extends BaseReader
         }
     }
 
+    /** @param null|bool|mixed[]|SimpleXMLElement $array */
     private static function getArrayItem(null|array|bool|SimpleXMLElement $array, int|string $key = 0): mixed
     {
         return ($array === null || is_bool($array)) ? null : ($array[$key] ?? null);
     }
 
+    /** @param null|bool|mixed[]|SimpleXMLElement $array */
     private static function getArrayItemString(null|array|bool|SimpleXMLElement $array, int|string $key = 0): string
     {
         $retVal = self::getArrayItem($array, $key);
@@ -2056,6 +2083,7 @@ class Xlsx extends BaseReader
         return StringHelper::convertToString($retVal, false);
     }
 
+    /** @param null|bool|mixed[]|SimpleXMLElement $array */
     private static function getArrayItemIntOrSxml(null|array|bool|SimpleXMLElement $array, int|string $key = 0): int|SimpleXMLElement
     {
         $retVal = self::getArrayItem($array, $key);
@@ -2071,6 +2099,7 @@ class Xlsx extends BaseReader
         return (string) preg_replace('~[^/]+/\.\./~', '', dirname($base) . "/$add");
     }
 
+    /** @return mixed[] */
     private static function toCSSArray(string $style): array
     {
         $style = self::stripWhiteSpaceFromStyleString($style);
@@ -2116,6 +2145,7 @@ class Xlsx extends BaseReader
         return $value === 'true' || $value === 'TRUE';
     }
 
+    /** @param string[] $hyperlinks */
     private function readHyperLinkDrawing(\PhpOffice\PhpSpreadsheet\Worksheet\Drawing $objDrawing, SimpleXMLElement $cellAnchor, array $hyperlinks): void
     {
         $hlinkClick = $cellAnchor->pic->nvPicPr->cNvPr->children(Namespaces::DRAWINGML)->hlinkClick;
@@ -2169,6 +2199,7 @@ class Xlsx extends BaseReader
         return $returnValue;
     }
 
+    /** @param mixed[][][][] $unparsedLoadedData */
     private function readFormControlProperties(Spreadsheet $excel, string $dir, string $fileWorksheet, Worksheet $docSheet, array &$unparsedLoadedData): void
     {
         $zip = $this->zip;
@@ -2185,6 +2216,7 @@ class Xlsx extends BaseReader
             }
         }
 
+        /** @var mixed[][] */
         $unparsedCtrlProps = &$unparsedLoadedData['sheets'][$docSheet->getCodeName()]['ctrlProps'];
         foreach ($ctrlProps as $rId => $ctrlProp) {
             $rId = substr($rId, 3); // rIdXXX
@@ -2196,6 +2228,7 @@ class Xlsx extends BaseReader
         unset($unparsedCtrlProps);
     }
 
+    /** @param mixed[][][][] $unparsedLoadedData */
     private function readPrinterSettings(Spreadsheet $excel, string $dir, string $fileWorksheet, Worksheet $docSheet, array &$unparsedLoadedData): void
     {
         $zip = $this->zip;
@@ -2212,6 +2245,7 @@ class Xlsx extends BaseReader
             }
         }
 
+        /** @var mixed[][] */
         $unparsedPrinterSettings = &$unparsedLoadedData['sheets'][$docSheet->getCodeName()]['printerSettings'];
         foreach ($sheetPrinterSettings as $rId => $printerSettings) {
             $rId = substr($rId, 3); // rIdXXX
@@ -2227,6 +2261,7 @@ class Xlsx extends BaseReader
         unset($unparsedPrinterSettings);
     }
 
+    /** @return array{string, string} */
     private function getWorkbookBaseName(): array
     {
         $workbookBasename = '';
@@ -2308,6 +2343,10 @@ class Xlsx extends BaseReader
         }
     }
 
+    /**
+     * @param TableDxfsStyle[] $tableStyles
+     * @param mixed[] $dxfs
+     */
     private function readTables(
         SimpleXMLElement $xmlSheet,
         Worksheet $docSheet,
@@ -2319,6 +2358,7 @@ class Xlsx extends BaseReader
         array $dxfs
     ): void {
         if ($xmlSheet && $xmlSheet->tableParts) {
+            /** @var array{count: scalar} */
             $attributes = $xmlSheet->tableParts->attributes() ?? ['count' => 0];
             if (((int) $attributes['count']) > 0) {
                 $this->readTablesInTablesFile($xmlSheet, $dir, $fileWorksheet, $zip, $docSheet, $namespaceTable, $tableStyles, $dxfs);
@@ -2326,6 +2366,10 @@ class Xlsx extends BaseReader
         }
     }
 
+    /**
+     * @param TableDxfsStyle[] $tableStyles
+     * @param mixed[] $dxfs
+     */
     private function readTablesInTablesFile(
         SimpleXMLElement $xmlSheet,
         string $dir,
@@ -2361,11 +2405,14 @@ class Xlsx extends BaseReader
         }
     }
 
+    /** @return mixed[] */
     private static function extractStyles(?SimpleXMLElement $sxml, string $node1, string $node2): array
     {
         $array = [];
         if ($sxml && $sxml->{$node1}->{$node2}) {
-            foreach ($sxml->{$node1}->{$node2} as $node) {
+            /** @var SimpleXMLElement */
+            $temp = $sxml->{$node1}->{$node2};
+            foreach ($temp as $node) {
                 $array[] = $node;
             }
         }
@@ -2373,6 +2420,7 @@ class Xlsx extends BaseReader
         return $array;
     }
 
+    /** @return string[] */
     private static function extractPalette(?SimpleXMLElement $sxml): array
     {
         $array = [];
@@ -2406,9 +2454,8 @@ class Xlsx extends BaseReader
                     $firstRow = $matches[2];
                     $firstCol = $matches[1];
                     if (array_key_exists(3, $matches)) {
-                        // https://github.com/phpstan/phpstan/issues/11602
-                        $lastCol = $matches[4]; // @phpstan-ignore-line
-                        $lastRow = $matches[5]; // @phpstan-ignore-line
+                        $lastCol = $matches[4];
+                        $lastRow = $matches[5];
                     } else {
                         $lastCol = $firstCol;
                         $lastRow = $firstRow;
@@ -2416,6 +2463,7 @@ class Xlsx extends BaseReader
                     ++$lastCol;
                     for ($row = $firstRow; $row <= $lastRow; ++$row) {
                         for ($col = $firstCol; $col !== $lastCol; ++$col) {
+                            /** @var string $col */
                             if (!$cellCollection->has2("$col$row")) {
                                 continue;
                             }
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/AutoFilter.php b/src/PhpSpreadsheet/Reader/Xlsx/AutoFilter.php
index 49fe3609d..88a08318e 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/AutoFilter.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/AutoFilter.php
@@ -51,6 +51,7 @@ class AutoFilter
                 //    Entries can be either filter elements
                 foreach ($filterColumn->filters->filter as $filterRule) {
                     //    Operator is undefined, but always treated as EQUAL
+                    /** @var SimpleXMLElement */
                     $attr2 = $filterRule->attributes() ?? ['val' => ''];
                     $column->createRule()->setRule('', (string) $attr2['val'])->setRuleType(Rule::AUTOFILTER_RULETYPE_FILTER);
                 }
@@ -103,6 +104,7 @@ class AutoFilter
                 $column->setJoin(Column::AUTOFILTER_COLUMN_JOIN_AND);
             }
             foreach ($customFilters->customFilter as $filterRule) {
+                /** @var SimpleXMLElement */
                 $attr2 = $filterRule->attributes() ?? ['operator' => '', 'val' => ''];
                 $column->createRule()->setRule(
                     (string) $attr2['operator'],
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Chart.php b/src/PhpSpreadsheet/Reader/Xlsx/Chart.php
index beca090da..22233c76b 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Chart.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Chart.php
@@ -858,6 +858,7 @@ class Chart
             $seriesValues = new DataSeriesValues(DataSeriesValues::DATASERIES_TYPE_STRING, $seriesSource, null, 0, null, $marker, $fillColor, "$pointSize");
 
             if (isset($seriesDetail->strRef->strCache)) {
+                /** @var array{formatCode: string, dataValues: mixed[]} */
                 $seriesData = $this->chartDataSeriesValues($seriesDetail->strRef->strCache->children($this->cNamespace), 's');
                 $seriesValues
                     ->setFormatCode($seriesData['formatCode'])
@@ -869,6 +870,7 @@ class Chart
             $seriesSource = (string) $seriesDetail->numRef->f;
             $seriesValues = new DataSeriesValues(DataSeriesValues::DATASERIES_TYPE_NUMBER, $seriesSource, null, 0, null, $marker, $fillColor, "$pointSize");
             if (isset($seriesDetail->numRef->numCache)) {
+                /** @var array{formatCode: string, dataValues: mixed[]} */
                 $seriesData = $this->chartDataSeriesValues($seriesDetail->numRef->numCache->children($this->cNamespace));
                 $seriesValues
                     ->setFormatCode($seriesData['formatCode'])
@@ -881,6 +883,7 @@ class Chart
             $seriesValues = new DataSeriesValues(DataSeriesValues::DATASERIES_TYPE_STRING, $seriesSource, null, 0, null, $marker, $fillColor, "$pointSize");
 
             if (isset($seriesDetail->multiLvlStrRef->multiLvlStrCache)) {
+                /** @var array{formatCode: string, dataValues: mixed[]} */
                 $seriesData = $this->chartDataSeriesValuesMultiLevel($seriesDetail->multiLvlStrRef->multiLvlStrCache->children($this->cNamespace), 's');
                 $seriesValues
                     ->setFormatCode($seriesData['formatCode'])
@@ -893,6 +896,7 @@ class Chart
             $seriesValues = new DataSeriesValues(DataSeriesValues::DATASERIES_TYPE_STRING, $seriesSource, null, 0, null, $marker, $fillColor, "$pointSize");
 
             if (isset($seriesDetail->multiLvlNumRef->multiLvlNumCache)) {
+                /** @var array{formatCode: string, dataValues: mixed[]} */
                 $seriesData = $this->chartDataSeriesValuesMultiLevel($seriesDetail->multiLvlNumRef->multiLvlNumCache->children($this->cNamespace), 's');
                 $seriesValues
                     ->setFormatCode($seriesData['formatCode'])
@@ -915,6 +919,7 @@ class Chart
         return null;
     }
 
+    /** @return mixed[] */
     private function chartDataSeriesValues(SimpleXMLElement $seriesValueSet, string $dataType = 'n'): array
     {
         $seriesVal = [];
@@ -953,6 +958,7 @@ class Chart
         ];
     }
 
+    /** @return mixed[] */
     private function chartDataSeriesValuesMultiLevel(SimpleXMLElement $seriesValueSet, string $dataType = 'n'): array
     {
         $seriesVal = [];
@@ -1220,6 +1226,7 @@ class Chart
         return $font;
     }
 
+    /** @return mixed[] */
     private function readChartAttributes(?SimpleXMLElement $chartDetail): array
     {
         $plotAttributes = [];
@@ -1277,9 +1284,11 @@ class Chart
         return $plotAttributes;
     }
 
+    /** @param array<mixed> $plotAttributes */
     private function setChartAttributes(Layout $plotArea, array $plotAttributes): void
     {
         foreach ($plotAttributes as $plotAttributeKey => $plotAttributeValue) {
+            /** @var ?bool $plotAttributeValue */
             switch ($plotAttributeKey) {
                 case 'showLegendKey':
                     $plotArea->setShowLegendKey($plotAttributeValue);
@@ -1310,6 +1319,7 @@ class Chart
 
                     break;
                 case 'labelFont':
+                    /** @var ?Font $plotAttributeValue */
                     $plotArea->setLabelFont($plotAttributeValue);
 
                     break;
@@ -1397,6 +1407,7 @@ class Chart
         'innerShdw',
     ];
 
+    /** @return array{type: ?string, value: ?string, alpha: ?int, brightness: ?int} */
     private function readColor(SimpleXMLElement $colorXml): array
     {
         $result = [
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/ColumnAndRowAttributes.php b/src/PhpSpreadsheet/Reader/Xlsx/ColumnAndRowAttributes.php
index 63dd4ade5..b82b5558f 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/ColumnAndRowAttributes.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/ColumnAndRowAttributes.php
@@ -24,8 +24,7 @@ class ColumnAndRowAttributes extends BaseParserClass
      * Set Worksheet column attributes by attributes array passed.
      *
      * @param string $columnAddress A, B, ... DX, ...
-     * @param array $columnAttributes array of attributes (indexes are attribute name, values are value)
-     *                               'xfIndex', 'visible', 'collapsed', 'outlineLevel', 'width', ... ?
+     * @param array{xfIndex?: int, visible?: bool, collapsed?: bool, collapsed?: bool, outlineLevel?: int, rowHeight?: float, width?: int} $columnAttributes array of attributes (indexes are attribute name, values are value)
      */
     private function setColumnAttributes(string $columnAddress, array $columnAttributes): void
     {
@@ -50,7 +49,7 @@ class ColumnAndRowAttributes extends BaseParserClass
      * Set Worksheet row attributes by attributes array passed.
      *
      * @param int $rowNumber 1, 2, 3, ... 99, ...
-     * @param array $rowAttributes array of attributes (indexes are attribute name, values are value)
+     * @param array{xfIndex?: int, visible?: bool, collapsed?: bool, collapsed?: bool, outlineLevel?: int, rowHeight?: float} $rowAttributes array of attributes (indexes are attribute name, values are value)
      *                               'xfIndex', 'visible', 'collapsed', 'outlineLevel', 'rowHeight', ... ?
      */
     private function setRowAttributes(int $rowNumber, array $rowAttributes): void
@@ -99,6 +98,7 @@ class ColumnAndRowAttributes extends BaseParserClass
                 || !$this->isFilteredColumn($readFilter, $columnCoordinate, $rowsAttributes)
             ) {
                 if (!isset($columnsAttributesAreSet[$columnCoordinate])) {
+                    /** @var array{xfIndex?: int, visible?: bool, collapsed?: bool, collapsed?: bool, outlineLevel?: int, rowHeight?: float, width?: int} $columnAttributes */
                     $this->setColumnAttributes($columnCoordinate, $columnAttributes);
                     $columnsAttributesAreSet[$columnCoordinate] = true;
                 }
@@ -112,6 +112,7 @@ class ColumnAndRowAttributes extends BaseParserClass
                 || !$this->isFilteredRow($readFilter, $rowCoordinate, $columnsAttributes)
             ) {
                 if (!isset($rowsAttributesAreSet[$rowCoordinate])) {
+                    /** @var array{xfIndex?: int, visible?: bool, collapsed?: bool, collapsed?: bool, outlineLevel?: int, rowHeight?: float} $rowAttributes */
                     $this->setRowAttributes($rowCoordinate, $rowAttributes);
                     $rowsAttributesAreSet[$rowCoordinate] = true;
                 }
@@ -119,6 +120,7 @@ class ColumnAndRowAttributes extends BaseParserClass
         }
     }
 
+    /** @param mixed[] $rowsAttributes */
     private function isFilteredColumn(IReadFilter $readFilter, string $columnCoordinate, array $rowsAttributes): bool
     {
         foreach ($rowsAttributes as $rowCoordinate => $rowAttributes) {
@@ -130,6 +132,7 @@ class ColumnAndRowAttributes extends BaseParserClass
         return true;
     }
 
+    /** @return mixed[] */
     private function readColumnAttributes(SimpleXMLElement $worksheetCols, bool $readDataOnly): array
     {
         $columnAttributes = [];
@@ -153,6 +156,7 @@ class ColumnAndRowAttributes extends BaseParserClass
         return $columnAttributes;
     }
 
+    /** @return mixed[] */
     private function readColumnRangeAttributes(?SimpleXMLElement $column, bool $readDataOnly): array
     {
         $columnAttributes = [];
@@ -177,6 +181,7 @@ class ColumnAndRowAttributes extends BaseParserClass
         return $columnAttributes;
     }
 
+    /** @param mixed[] $columnsAttributes */
     private function isFilteredRow(IReadFilter $readFilter, int $rowCoordinate, array $columnsAttributes): bool
     {
         foreach ($columnsAttributes as $columnCoordinate => $columnAttributes) {
@@ -188,6 +193,7 @@ class ColumnAndRowAttributes extends BaseParserClass
         return false;
     }
 
+    /** @return mixed[] */
     private function readRowAttributes(SimpleXMLElement $worksheetRow, bool $readDataOnly, bool $ignoreRowsWithNoCells, bool $readFilterIsNotNull): array
     {
         $rowAttributes = [];
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/ConditionalStyles.php b/src/PhpSpreadsheet/Reader/Xlsx/ConditionalStyles.php
index 436d9ffb8..b09de2ad6 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/ConditionalStyles.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/ConditionalStyles.php
@@ -20,12 +20,15 @@ class ConditionalStyles
 
     private SimpleXMLElement $worksheetXml;
 
+    /** @var string[] */
     private array $ns;
 
+    /** @var Style[] */
     private array $dxfs;
 
     private StyleReader $styleReader;
 
+    /** @param Style[] $dxfs */
     public function __construct(Worksheet $workSheet, SimpleXMLElement $worksheetXml, array $dxfs, StyleReader $styleReader)
     {
         $this->worksheet = $workSheet;
@@ -59,6 +62,7 @@ class ConditionalStyles
         $this->worksheet->setSelectedCells($selectedCells);
     }
 
+    /** @param Conditional[][] $conditionals */
     private function setConditionalsFromExt(array $conditionals): void
     {
         foreach ($conditionals as $conditionalRange => $cfRules) {
@@ -70,6 +74,7 @@ class ConditionalStyles
         }
     }
 
+    /** @return array<string, array<int, Conditional>> */
     private function readConditionalsFromExt(SimpleXMLElement $extLst): array
     {
         $conditionals = [];
@@ -167,6 +172,7 @@ class ConditionalStyles
         return $cfStyle;
     }
 
+    /** @return mixed[] */
     private function readConditionalStyles(SimpleXMLElement $xmlSheet): array
     {
         $conditionals = [];
@@ -183,9 +189,11 @@ class ConditionalStyles
         return $conditionals;
     }
 
+    /** @param mixed[] $conditionals */
     private function setConditionalStyles(Worksheet $worksheet, array $conditionals, SimpleXMLElement $xmlExtLst): void
     {
         foreach ($conditionals as $cellRangeReference => $cfRules) {
+            /** @var mixed[] $cfRules */
             ksort($cfRules); // no longer needed for Xlsx, but helps Xls
             $conditionalStyles = $this->readStyleRules($cfRules, $xmlExtLst);
 
@@ -204,8 +212,14 @@ class ConditionalStyles
         }
     }
 
+    /**
+     * @param mixed[] $cfRules
+     *
+     * @return Conditional[]
+     */
     private function readStyleRules(array $cfRules, SimpleXMLElement $extLst): array
     {
+        /** @var ConditionalFormattingRuleExtension[] */
         $conditionalFormattingRuleExtensions = ConditionalFormattingRuleExtension::parseExtLstXml($extLst);
         $conditionalStyles = [];
 
@@ -261,6 +275,7 @@ class ConditionalStyles
         return $conditionalStyles;
     }
 
+    /** @param ConditionalFormattingRuleExtension[] $conditionalFormattingRuleExtensions */
     private function readDataBarOfConditionalRule(SimpleXMLElement $cfRule, array $conditionalFormattingRuleExtensions): ConditionalDataBar
     {
         $dataBar = new ConditionalDataBar();
@@ -274,6 +289,7 @@ class ConditionalStyles
         $cfvoXml = $cfRule->dataBar->cfvo;
         $cfvoIndex = 0;
         foreach ((count($cfvoXml) > 1 ? $cfvoXml : [$cfvoXml]) as $cfvo) { //* @phpstan-ignore-line
+            /** @var SimpleXMLElement $cfvo */
             if ($cfvoIndex === 0) {
                 $dataBar->setMinimumConditionalFormatValueObject(new ConditionalFormatValueObject((string) $cfvo['type'], (string) $cfvo['val']));
             }
@@ -296,6 +312,7 @@ class ConditionalStyles
     private function readColorScale(SimpleXMLElement|stdClass $cfRule): ConditionalColorScale
     {
         $colorScale = new ConditionalColorScale();
+        /** @var SimpleXMLElement $cfRule */
         $count = count($cfRule->colorScale->cfvo);
         $idx = 0;
         foreach ($cfRule->colorScale->cfvo as $cfvoXml) {
@@ -332,11 +349,13 @@ class ConditionalStyles
         return $colorScale;
     }
 
+    /** @param ConditionalFormattingRuleExtension[] $conditionalFormattingRuleExtensions */
     private function readDataBarExtLstOfConditionalRule(ConditionalDataBar $dataBar, SimpleXMLElement $cfRule, array $conditionalFormattingRuleExtensions): void
     {
         if (isset($cfRule->extLst)) {
             $ns = $cfRule->extLst->getNamespaces(true);
             foreach ((count($cfRule->extLst) > 0 ? $cfRule->extLst->ext : [$cfRule->extLst->ext]) as $ext) { //* @phpstan-ignore-line
+                /** @var SimpleXMLElement $ext */
                 $extId = (string) $ext->children($ns['x14'])->id;
                 if (isset($conditionalFormattingRuleExtensions[$extId]) && (string) $ext['uri'] === '{B025F937-C7B1-47D3-B67F-A62EFF666E3E}') {
                     $dataBar->setConditionalFormattingRuleExt($conditionalFormattingRuleExtensions[$extId]);
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
index 3eae5bb39..2c2d4af4b 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
@@ -11,6 +11,7 @@ class Hyperlinks
 {
     private Worksheet $worksheet;
 
+    /** @var string[] */
     private array $hyperlinks = [];
 
     public function __construct(Worksheet $workSheet)
@@ -44,7 +45,7 @@ class Hyperlinks
         foreach (Coordinate::extractAllCellReferencesInRange($attributes->ref) as $cellReference) {
             $cell = $worksheet->getCell($cellReference);
             if (isset($linkRel['id'])) {
-                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']] ?? null;
+                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']] ?? '';
                 if (isset($attributes['location'])) {
                     $hyperlinkUrl .= '#' . (string) $attributes['location'];
                 }
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/PageSetup.php b/src/PhpSpreadsheet/Reader/Xlsx/PageSetup.php
index ca6ae0b09..766154e5b 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/PageSetup.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/PageSetup.php
@@ -18,6 +18,11 @@ class PageSetup extends BaseParserClass
         $this->worksheetXml = $worksheetXml;
     }
 
+    /**
+     * @param mixed[] $unparsedLoadedData
+     *
+     * @return mixed[]
+     */
     public function load(array $unparsedLoadedData): array
     {
         $worksheetXml = $this->worksheetXml;
@@ -46,6 +51,11 @@ class PageSetup extends BaseParserClass
         }
     }
 
+    /**
+     * @param mixed[] $unparsedLoadedData
+     *
+     * @return mixed[]
+     */
     private function pageSetup(SimpleXMLElement $xmlSheet, Worksheet $worksheet, array $unparsedLoadedData): array
     {
         if ($xmlSheet->pageSetup) {
@@ -82,6 +92,7 @@ class PageSetup extends BaseParserClass
                 if (!str_ends_with($relid, 'ps')) {
                     $relid .= 'ps';
                 }
+                /** @var mixed[][][] $unparsedLoadedData */
                 $unparsedLoadedData['sheets'][$worksheet->getCodeName()]['pageSetupRelId'] = $relid;
             }
         }
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Properties.php b/src/PhpSpreadsheet/Reader/Xlsx/Properties.php
index 1a0517b19..a792235af 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Properties.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Properties.php
@@ -79,7 +79,9 @@ class Properties
                     $cellDataOfficeChildren = $xmlProperty->children('http://schemas.openxmlformats.org/officeDocument/2006/docPropsVTypes');
 
                     $attributeType = $cellDataOfficeChildren->getName();
-                    $attributeValue = (string) $cellDataOfficeChildren->{$attributeType};
+                    /** @var SimpleXMLElement */
+                    $attributeValue = $cellDataOfficeChildren->{$attributeType};
+                    $attributeValue = (string) $attributeValue;
                     $attributeValue = DocumentProperties::convertProperty($attributeValue, $attributeType);
                     $attributeType = DocumentProperties::convertPropertyType($attributeType);
                     $this->docProps->setCustomProperty($propertyName, $attributeValue, $attributeType);
@@ -88,6 +90,7 @@ class Properties
         }
     }
 
+    /** @param null|false|scalar[] $array */
     private function getArrayItem(null|array|false $array): string
     {
         return is_array($array) ? (string) ($array[0] ?? '') : '';
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Styles.php b/src/PhpSpreadsheet/Reader/Xlsx/Styles.php
index c1e27e9e3..5729add76 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Styles.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Styles.php
@@ -23,10 +23,13 @@ class Styles extends BaseParserClass
      */
     private ?Theme $theme = null;
 
+    /** @var mixed[] */
     private array $workbookPalette = [];
 
+    /** @var mixed[] */
     private array $styles = [];
 
+    /** @var array<SimpleXMLElement|stdClass> */
     private array $cellStyles = [];
 
     private SimpleXMLElement $styleXml;
@@ -38,6 +41,7 @@ class Styles extends BaseParserClass
         $this->namespace = $namespace;
     }
 
+    /** @param mixed[] $palette */
     public function setWorkbookPalette(array $palette): void
     {
         $this->workbookPalette = $palette;
@@ -63,6 +67,10 @@ class Styles extends BaseParserClass
         $this->theme = $theme;
     }
 
+    /**
+     * @param mixed[] $styles
+     * @param array<SimpleXMLElement|stdClass> $cellStyles
+     */
     public function setStyleBaseData(?Theme $theme = null, array $styles = [], array $cellStyles = []): void
     {
         $this->theme = $theme;
@@ -310,9 +318,12 @@ class Styles extends BaseParserClass
         if ($style instanceof SimpleXMLElement) {
             $this->readNumberFormat($docStyle->getNumberFormat(), $style->numFmt);
         } else {
-            $docStyle->getNumberFormat()->setFormatCode(self::formatGeneral((string) $style->numFmt));
+            /** @var SimpleXMLElement */
+            $temp = $style->numFmt;
+            $docStyle->getNumberFormat()->setFormatCode(self::formatGeneral((string) $temp));
         }
 
+        /** @var SimpleXMLElement $style */
         if (isset($style->font)) {
             $this->readFontStyle($docStyle->getFont(), $style->font);
         }
@@ -416,6 +427,7 @@ class Styles extends BaseParserClass
         return ($background) ? 'FFFFFFFF' : 'FF000000';
     }
 
+    /** @return mixed[] */
     public function dxfs(bool $readDataOnly = false): array
     {
         $dxfs = [];
@@ -448,7 +460,7 @@ class Styles extends BaseParserClass
         return $dxfs;
     }
 
-    // get TableStyles
+    /** @return TableDxfsStyle[] */
     public function tableStyles(bool $readDataOnly = false): array
     {
         $tableStyles = [];
@@ -488,6 +500,7 @@ class Styles extends BaseParserClass
         return $tableStyles;
     }
 
+    /** @return mixed[] */
     public function styles(): array
     {
         return $this->styles;
@@ -496,7 +509,7 @@ class Styles extends BaseParserClass
     /**
      * Get array item.
      *
-     * @param mixed $array (usually array, in theory can be false)
+     * @param false|mixed[] $array (usually array, in theory can be false)
      */
     private static function getArrayItem(mixed $array): ?SimpleXMLElement
     {
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/TableReader.php b/src/PhpSpreadsheet/Reader/Xlsx/TableReader.php
index c84b8198f..c82195866 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/TableReader.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/TableReader.php
@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheet\Reader\Xlsx;
 
 use PhpOffice\PhpSpreadsheet\Worksheet\Table;
+use PhpOffice\PhpSpreadsheet\Worksheet\Table\TableDxfsStyle;
 use PhpOffice\PhpSpreadsheet\Worksheet\Table\TableStyle;
 use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 use SimpleXMLElement;
@@ -13,7 +14,7 @@ class TableReader
 
     private SimpleXMLElement $tableXml;
 
-    /** @var array|SimpleXMLElement */
+    /** @var mixed[]|SimpleXMLElement */
     private $tableAttributes;
 
     public function __construct(Worksheet $workSheet, SimpleXMLElement $tableXml)
@@ -24,6 +25,9 @@ class TableReader
 
     /**
      * Loads Table into the Worksheet.
+     *
+     * @param TableDxfsStyle[] $tableStyles
+     * @param mixed[] $dxfs
      */
     public function load(array $tableStyles, array $dxfs): void
     {
@@ -37,13 +41,18 @@ class TableReader
 
     /**
      * Read Table from xml.
+     *
+     * @param TableDxfsStyle[] $tableStyles
+     * @param mixed[] $dxfs
      */
     private function readTable(string $tableRange, array $tableStyles, array $dxfs): void
     {
         $table = new Table($tableRange);
-        $table->setName((string) ($this->tableAttributes['displayName'] ?? ''));
-        $table->setShowHeaderRow(((string) ($this->tableAttributes['headerRowCount'] ?? '')) !== '0');
-        $table->setShowTotalsRow(((string) ($this->tableAttributes['totalsRowCount'] ?? '')) === '1');
+        /** @var string[] */
+        $attributes = $this->tableAttributes;
+        $table->setName((string) ($attributes['displayName'] ?? ''));
+        $table->setShowHeaderRow(((string) ($attributes['headerRowCount'] ?? '')) !== '0');
+        $table->setShowTotalsRow(((string) ($attributes['totalsRowCount'] ?? '')) === '1');
 
         $this->readTableAutoFilter($table, $this->tableXml->autoFilter);
         $this->readTableColumns($table, $this->tableXml->tableColumns);
@@ -65,6 +74,7 @@ class TableReader
         }
 
         foreach ($autoFilterXml->filterColumn as $filterColumn) {
+            /** @var SimpleXMLElement */
             $attributes = $filterColumn->attributes() ?? ['colId' => 0, 'hiddenButton' => 0];
             $column = $table->getColumnByOffset((int) $attributes['colId']);
             $column->setShowFilterButton(((string) $attributes['hiddenButton']) !== '1');
@@ -78,6 +88,7 @@ class TableReader
     {
         $offset = 0;
         foreach ($tableColumnsXml->tableColumn as $tableColumn) {
+            /** @var SimpleXMLElement */
             $attributes = $tableColumn->attributes() ?? ['totalsRowLabel' => 0, 'totalsRowFunction' => 0];
             $column = $table->getColumnByOffset($offset++);
 
@@ -99,6 +110,9 @@ class TableReader
 
     /**
      * Reads TableStyle from xml.
+     *
+     * @param TableDxfsStyle[] $tableStyles
+     * @param mixed[] $dxfs
      */
     private function readTableStyle(Table $table, SimpleXMLElement $tableStyleInfoXml, array $tableStyles, array $dxfs): void
     {
diff --git a/src/PhpSpreadsheet/Reader/Xlsx/WorkbookView.php b/src/PhpSpreadsheet/Reader/Xlsx/WorkbookView.php
index f02de9a84..429efb089 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/WorkbookView.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/WorkbookView.php
@@ -14,6 +14,7 @@ class WorkbookView
         $this->spreadsheet = $spreadsheet;
     }
 
+    /** @param array<int, ?int> $mapSheetId */
     public function viewSettings(SimpleXMLElement $xmlWorkbook, string $mainNS, array $mapSheetId, bool $readDataOnly): void
     {
         // Default active sheet index to the first loaded worksheet from the file
diff --git a/src/PhpSpreadsheet/Shared/Escher/DgContainer/SpgrContainer.php b/src/PhpSpreadsheet/Shared/Escher/DgContainer/SpgrContainer.php
index 84363ab20..04fb2234d 100644
--- a/src/PhpSpreadsheet/Shared/Escher/DgContainer/SpgrContainer.php
+++ b/src/PhpSpreadsheet/Shared/Escher/DgContainer/SpgrContainer.php
@@ -65,6 +65,7 @@ class SpgrContainer
                 $allSpContainers[] = $child;
             }
         }
+        /** @var SpgrContainer\SpContainer[] $allSpContainers */
 
         return $allSpContainers;
     }
diff --git a/src/PhpSpreadsheet/Style/Font.php b/src/PhpSpreadsheet/Style/Font.php
index 7d70dc4f7..89a099ee1 100644
--- a/src/PhpSpreadsheet/Style/Font.php
+++ b/src/PhpSpreadsheet/Style/Font.php
@@ -560,6 +560,7 @@ class Font extends Supervisor
         return $this->underlineColor;
     }
 
+    /** @param array{value: ?string, alpha: null|int|string, brightness?: null|int|string, type: ?string}  $colorArray */
     public function setUnderlineColor(array $colorArray): self
     {
         if (!$this->isSupervisor) {
@@ -584,6 +585,7 @@ class Font extends Supervisor
         return $this->chartColor;
     }
 
+    /** @param array{value: ?string, alpha: null|int|string, brightness?: null|int|string, type: ?string}  $colorArray */
     public function setChartColor(array $colorArray): self
     {
         if (!$this->isSupervisor) {
diff --git a/src/PhpSpreadsheet/Worksheet/Worksheet.php b/src/PhpSpreadsheet/Worksheet/Worksheet.php
index 9863f7223..33792a4da 100644
--- a/src/PhpSpreadsheet/Worksheet/Worksheet.php
+++ b/src/PhpSpreadsheet/Worksheet/Worksheet.php
@@ -355,7 +355,7 @@ class Worksheet
      */
     public function disconnectCells(): void
     {
-        if (isset($this->cellCollection)) {
+        if (isset($this->cellCollection)) { //* @phpstan-ignore-line
             $this->cellCollection->unsetWorksheetCells();
             unset($this->cellCollection);
         }
@@ -456,7 +456,7 @@ class Worksheet
      */
     public function getCoordinates(bool $sorted = true): array
     {
-        if (!isset($this->cellCollection)) {
+        if (!isset($this->cellCollection)) { //* @phpstan-ignore-line
             return [];
         }
 
@@ -2897,6 +2897,8 @@ class Worksheet
      *                             True - Return rows and columns indexed by their actual row and column IDs
      * @param bool $ignoreHidden False - Return values for rows/columns even if they are defined as hidden.
      *                            True - Don't return values for rows/columns that are defined as hidden.
+     *
+     * @return mixed[][]
      */
     public function rangeToArray(
         string $range,
@@ -3116,6 +3118,8 @@ class Worksheet
      *                             True - Return rows and columns indexed by their actual row and column IDs
      * @param bool $ignoreHidden False - Return values for rows/columns even if they are defined as hidden.
      *                            True - Don't return values for rows/columns that are defined as hidden.
+     *
+     * @return mixed[][]
      */
     public function namedRangeToArray(
         string $definedName,
@@ -3150,6 +3154,8 @@ class Worksheet
      *                             True - Return rows and columns indexed by their actual row and column IDs
      * @param bool $ignoreHidden False - Return values for rows/columns even if they are defined as hidden.
      *                            True - Don't return values for rows/columns that are defined as hidden.
+     *
+     * @return mixed[][]
      */
     public function toArray(
         mixed $nullValue = null,
diff --git a/src/PhpSpreadsheet/Writer/Html.php b/src/PhpSpreadsheet/Writer/Html.php
index 4a85955c1..01a35f4d1 100644
--- a/src/PhpSpreadsheet/Writer/Html.php
+++ b/src/PhpSpreadsheet/Writer/Html.php
@@ -1330,7 +1330,7 @@ class Html extends BaseWriter
         return $html;
     }
 
-    /** @return array{null|''|Cell, array{}|non-falsy-string, non-empty-string} */
+    /** @return array{null|''|Cell, array{}|string, non-empty-string} */
     private function generateRowCellCss(Worksheet $worksheet, string $cellAddress, int $row, int $columnNumber): array
     {
         $cell = ($cellAddress > '') ? $worksheet->getCellCollection()->get($cellAddress) : '';
diff --git a/tests/PhpSpreadsheetTests/Calculation/Functions/LookupRef/IndirectTest.php b/tests/PhpSpreadsheetTests/Calculation/Functions/LookupRef/IndirectTest.php
index 176d96a50..b19339c9c 100644
--- a/tests/PhpSpreadsheetTests/Calculation/Functions/LookupRef/IndirectTest.php
+++ b/tests/PhpSpreadsheetTests/Calculation/Functions/LookupRef/IndirectTest.php
@@ -107,13 +107,13 @@ class IndirectTest extends AllSetupTeardown
     {
         $reader = new ReaderXlsx();
         $file = 'tests/data/Calculation/LookupRef/IndirectFormulaSelection.xlsx';
-        $this->spreadsheet = $reader->load($file);
-        $sheet = $this->spreadsheet->getActiveSheet();
+        $spreadsheet = $this->spreadsheet = $reader->load($file);
+        $sheet = $spreadsheet->getActiveSheet();
         $result = $sheet->getCell('A5')->getCalculatedValue();
         self::assertSame(100, $result);
         $value = $sheet->getCell('A5')->getValue();
         self::assertSame('=CURRENCY_SELECTOR', $value);
-        $formula = $this->spreadsheet->getNamedFormula('CURRENCY_SELECTOR');
+        $formula = $spreadsheet->getNamedFormula('CURRENCY_SELECTOR');
         if ($formula === null) {
             self::fail('Expected named formula was not defined');
         } else {
diff --git a/tests/PhpSpreadsheetTests/Custom/ComplexAssert.php b/tests/PhpSpreadsheetTests/Custom/ComplexAssert.php
index 45b734958..ddaf16d89 100644
--- a/tests/PhpSpreadsheetTests/Custom/ComplexAssert.php
+++ b/tests/PhpSpreadsheetTests/Custom/ComplexAssert.php
@@ -15,7 +15,8 @@ class ComplexAssert extends TestCase
 
     public function __construct()
     {
-        parent::__construct('complexAssert');
+        // Phpstan doesn't want you to use "internal" method outside PHPunit namespace
+        parent::__construct('complexAssert'); //* @phpstan-ignore-line
     }
 
     private function testExpectedExceptions(string|float $expected, string|float $actual): bool
diff --git a/tests/PhpSpreadsheetTests/Helper/SampleTest.php b/tests/PhpSpreadsheetTests/Helper/SampleTest.php
index 3759ff17a..6020f1d91 100644
--- a/tests/PhpSpreadsheetTests/Helper/SampleTest.php
+++ b/tests/PhpSpreadsheetTests/Helper/SampleTest.php
@@ -31,6 +31,7 @@ class SampleTest extends TestCase
 
         // Unfortunately some tests are too long to run with code-coverage
         // analysis on GitHub Actions, so we need to exclude them
+        /** @var string[] */
         global $argv;
         if (in_array('--coverage-clover', $argv)) {
             $tooLongToBeCovered = [
diff --git a/tests/PhpSpreadsheetTests/Helper/TextGridTest.php b/tests/PhpSpreadsheetTests/Helper/TextGridTest.php
index 505e9198d..236326029 100644
--- a/tests/PhpSpreadsheetTests/Helper/TextGridTest.php
+++ b/tests/PhpSpreadsheetTests/Helper/TextGridTest.php
@@ -11,6 +11,7 @@ use PHPUnit\Framework\TestCase;
 
 class TextGridTest extends TestCase
 {
+    /** @param mixed[] $expected */
     #[DataProvider('providerTextGrid')]
     public function testTextGrid(
         bool $cli,
@@ -26,8 +27,10 @@ class TextGridTest extends TestCase
             ['="6"', '=TEXT(A2,"yyyy-mm-dd hh:mm")', null, '1<>2'],
             ['xyz', '=TEXT(A3,"yyyy-mm-dd hh:mm")'],
         ], strictNullComparison: true);
+        /** @var mixed[][] */
+        $temp = $sheet->toArray(null, true, true, true);
         $textGrid = new TextGrid(
-            $sheet->toArray(null, true, true, true),
+            $temp,
             $cli,
             rowDividers: $rowDividers,
             rowHeaders: $rowHeaders,
@@ -136,8 +139,10 @@ class TextGridTest extends TestCase
             [true, false],
             [true, true],
         ], strictNullComparison: true);
+        /** @var mixed[][] */
+        $temp = $sheet->toArray(null, true, false, true);
         $textGrid = new TextGrid(
-            $sheet->toArray(null, true, false, true),
+            $temp,
             true,
             rowDividers: false,
             rowHeaders: false,
diff --git a/tests/PhpSpreadsheetTests/Reader/Html/HtmlBorderTest.php b/tests/PhpSpreadsheetTests/Reader/Html/HtmlBorderTest.php
index b516de04c..d3e86fe8c 100644
--- a/tests/PhpSpreadsheetTests/Reader/Html/HtmlBorderTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Html/HtmlBorderTest.php
@@ -94,6 +94,7 @@ class HtmlBorderTest extends TestCase
         }
         $tests = $this->providerBorderStyle();
         foreach ($tests as $test) {
+            /** @var array<int, int|string> $test */
             $covered[$test[0]] = 1;
         }
         foreach ($covered as $key => $val) {
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingBasicTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingBasicTest.php
index ee39c7ce2..ead2d4a26 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingBasicTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingBasicTest.php
@@ -7,11 +7,13 @@ namespace PhpOffice\PhpSpreadsheetTests\Reader\Xls;
 use PhpOffice\PhpSpreadsheet\Reader\Xls;
 use PhpOffice\PhpSpreadsheet\Style\Border;
 use PhpOffice\PhpSpreadsheet\Style\Conditional;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 class ConditionalFormattingBasicTest extends TestCase
 {
-    #[\PHPUnit\Framework\Attributes\DataProvider('conditionalFormattingProvider')]
+    /** @param mixed[][] $expectedRules */
+    #[DataProvider('conditionalFormattingProvider')]
     public function testReadConditionalFormatting(string $expectedRange, array $expectedRules): void
     {
         $filename = 'tests/data/Reader/XLS/CF_Basic_Comparisons.xls';
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingExpressionTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingExpressionTest.php
index eb7a67916..62e319356 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingExpressionTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/ConditionalFormattingExpressionTest.php
@@ -6,11 +6,13 @@ namespace PhpOffice\PhpSpreadsheetTests\Reader\Xls;
 
 use PhpOffice\PhpSpreadsheet\Reader\Xls;
 use PhpOffice\PhpSpreadsheet\Style\Conditional;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 class ConditionalFormattingExpressionTest extends TestCase
 {
-    #[\PHPUnit\Framework\Attributes\DataProvider('conditionalFormattingProvider')]
+    /** @param mixed[][] $expectedRule */
+    #[DataProvider('conditionalFormattingProvider')]
     public function testReadConditionalFormatting(string $expectedRange, array $expectedRule): void
     {
         $filename = 'tests/data/Reader/XLS/CF_Expression_Comparisons.xls';
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/DataValidationTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/DataValidationTest.php
index 3d30e8ab6..621d0890a 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/DataValidationTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/DataValidationTest.php
@@ -6,11 +6,13 @@ namespace PhpOffice\PhpSpreadsheetTests\Reader\Xls;
 
 use PhpOffice\PhpSpreadsheet\Cell\DataValidation;
 use PhpOffice\PhpSpreadsheet\Reader\Xls;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 class DataValidationTest extends TestCase
 {
-    #[\PHPUnit\Framework\Attributes\DataProvider('dataValidationProvider')]
+    /** @param mixed[] $expectedRule */
+    #[DataProvider('dataValidationProvider')]
     public function testDataValidation(string $expectedRange, array $expectedRule): void
     {
         $filename = 'tests/data/Reader/XLS/DataValidation.xls';
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/HiddenWorksheetTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/HiddenWorksheetTest.php
index 3a2949a51..b9aac4c7f 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/HiddenWorksheetTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/HiddenWorksheetTest.php
@@ -38,6 +38,7 @@ class HiddenWorksheetTest extends TestCase
         $spreadsheet->disconnectWorksheets();
     }
 
+    /** @return string[][] */
     private function worksheetAssertions(): array
     {
         return [
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/LoadSheetsOnlyTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/LoadSheetsOnlyTest.php
index c8c543afd..2c8f50ecc 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/LoadSheetsOnlyTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/LoadSheetsOnlyTest.php
@@ -30,9 +30,9 @@ class LoadSheetsOnlyTest extends TestCase
         //$reader->setLoadSheetsOnly(['Sheet1']);
         $names = $reader->listWorksheetNames($filename);
         $reader->setLoadSheetsOnly([$names[0]]);
-        $this->spreadsheet = $reader->load($filename);
-        self::assertSame(1, $this->spreadsheet->getSheetCount());
-        self::assertSame('Sheet1', $this->spreadsheet->getActiveSheet()->getTitle());
+        $spreadsheet = $this->spreadsheet = $reader->load($filename);
+        self::assertSame(1, $spreadsheet->getSheetCount());
+        self::assertSame('Sheet1', $spreadsheet->getActiveSheet()->getTitle());
     }
 
     public function testLoadSheet2Only(): void
@@ -40,9 +40,9 @@ class LoadSheetsOnlyTest extends TestCase
         $filename = self::$testbook;
         $reader = new Xls();
         $reader->setLoadSheetsOnly(['Sheet2']);
-        $this->spreadsheet = $reader->load($filename);
-        self::assertSame(1, $this->spreadsheet->getSheetCount());
-        self::assertSame('Sheet2', $this->spreadsheet->getActiveSheet()->getTitle());
+        $spreadsheet = $this->spreadsheet = $reader->load($filename);
+        self::assertSame(1, $spreadsheet->getSheetCount());
+        self::assertSame('Sheet2', $spreadsheet->getActiveSheet()->getTitle());
     }
 
     public function testLoadNoSheet(): void
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/PageSetupTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/PageSetupTest.php
index 2eb2bc633..30f5b45ff 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xls/PageSetupTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/PageSetupTest.php
@@ -73,6 +73,7 @@ class PageSetupTest extends TestCase
         $spreadsheet->disconnectWorksheets();
     }
 
+    /** @return array<array{orientation: string, scale: int, horizontalCentered: bool, verticalCentered: bool, pageOrder: string}> */
     private function pageSetupAssertions(): array
     {
         return [
@@ -108,6 +109,7 @@ class PageSetupTest extends TestCase
         ];
     }
 
+    /** @return array<array{top: float, header: float, left: float, right: float, bottom: float, footer: float}> */
     private function pageMarginAssertions(): array
     {
         return [
diff --git a/tests/PhpSpreadsheetTests/Reader/Xls/PasswordTest.php b/tests/PhpSpreadsheetTests/Reader/Xls/PasswordTest.php
new file mode 100644
index 000000000..bf5a62882
--- /dev/null
+++ b/tests/PhpSpreadsheetTests/Reader/Xls/PasswordTest.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Reader\Xls;
+
+use PhpOffice\PhpSpreadsheet\Reader\Exception as ReaderException;
+use PhpOffice\PhpSpreadsheet\Reader\Xls as XlsReader;
+use PHPUnit\Framework\TestCase;
+
+class PasswordTest extends TestCase
+{
+    public function testDefaultPassword(): void
+    {
+        $filename = 'tests/data/Reader/XLS/pwtest.xls';
+        $reader = new XlsReader();
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame('x', $sheet->getCell('A1')->getValue());
+        $spreadsheet->disconnectWorksheets();
+    }
+
+    public function testWrongPassword(): void
+    {
+        $this->expectException(ReaderException::class);
+        $this->expectExceptionMessage('Decryption password incorrect');
+        $filename = 'tests/data/Reader/XLS/pwtest2.xls';
+        $reader = new XlsReader();
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame('test2', $sheet->getCell('A1')->getValue());
+        $spreadsheet->disconnectWorksheets();
+    }
+
+    public function testCorrectPassword(): void
+    {
+        $filename = 'tests/data/Reader/XLS/pwtest2.xls';
+        $reader = new XlsReader();
+        $reader->setEncryptionPassword('pwtest2');
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame('test2', $sheet->getCell('A1')->getValue());
+        $spreadsheet->disconnectWorksheets();
+    }
+
+    public function testUnsupportedEncryption(): void
+    {
+        $this->expectException(ReaderException::class);
+        $this->expectExceptionMessage('Unsupported encryption algorithm');
+        $filename = 'tests/data/Reader/XLS/pwtest3.xls';
+        $reader = new XlsReader();
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame('test2', $sheet->getCell('A1')->getValue());
+        $spreadsheet->disconnectWorksheets();
+    }
+}
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilter2Test.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilter2Test.php
index e14c6a24a..1aa9fb7d0 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilter2Test.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilter2Test.php
@@ -13,6 +13,7 @@ class AutoFilter2Test extends TestCase
 {
     private const TESTBOOK = 'tests/data/Reader/XLSX/autofilter2.xlsx';
 
+    /** @return int[] */
     public function getVisibleSheet(?Worksheet $sheet, int $maxRow): array
     {
         $actualVisible = [];
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilterEvaluateTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilterEvaluateTest.php
index 70f332a16..25045bd8c 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilterEvaluateTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/AutoFilterEvaluateTest.php
@@ -12,6 +12,7 @@ use PhpOffice\PhpSpreadsheetTests\Functional\AbstractFunctional;
 
 class AutoFilterEvaluateTest extends AbstractFunctional
 {
+    /** @return int[] */
     private function getVisibleSheet(Worksheet $sheet): array
     {
         $actualVisible = [];
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/CommentTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/CommentTest.php
index 1eb9eca01..13e1996f2 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/CommentTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/CommentTest.php
@@ -66,9 +66,12 @@ class CommentTest extends TestCase
 
         // Spreadsheet generated by Flexcel. Make sure we managed
         // to locate printerSettings since it used an unexpected link.
-        $pageSetupRel = $spreadsheet->getUnparsedLoadedData()['sheets']['Worksheet']['pageSetupRelId'] ?? '';
+        /** @var mixed[][][][][] */
+        $unparsedLoadedData = $spreadsheet->getUnparsedLoadedData();
+        /** @var string */
+        $pageSetupRel = $unparsedLoadedData['sheets']['Worksheet']['pageSetupRelId'] ?? '';
         self::assertSame('flId1ps', $pageSetupRel);
-        $pageSetupPath = $spreadsheet->getUnparsedLoadedData()['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
+        $pageSetupPath = $unparsedLoadedData['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
         self::assertSame('xl/printerSettings/printerSettings1.bin', $pageSetupPath);
         $spreadsheet->disconnectWorksheets();
     }
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/HiddenWorksheetTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/HiddenWorksheetTest.php
index f6017a120..c7a3b8175 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/HiddenWorksheetTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/HiddenWorksheetTest.php
@@ -35,6 +35,7 @@ class HiddenWorksheetTest extends TestCase
         $spreadsheet->disconnectWorksheets();
     }
 
+    /** @return array<array{sheetState: string}> */
     private function worksheetAssertions(): array
     {
         return [
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3126Test.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3126Test.php
index 8a1d3d7d1..31a98d5a9 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3126Test.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3126Test.php
@@ -22,9 +22,12 @@ class Issue3126Test extends TestCase
         self::assertCount(1, $gen1Images);
         $gen1hfName = array_key_exists('LF', $gen1Images) ? $gen1Images['LF']->getName() : '';
         self::assertSame('fleche-verte-up-right', $gen1hfName);
-        $pageSetupRel = $generation1->getUnparsedLoadedData()['sheets']['Worksheet']['pageSetupRelId'] ?? '';
+        /** @var mixed[][][][][] */
+        $unparsedLoadedData = $generation1->getUnparsedLoadedData();
+        /** @var string */
+        $pageSetupRel = $unparsedLoadedData['sheets']['Worksheet']['pageSetupRelId'] ?? '';
         self::assertSame('rId1ps', $pageSetupRel);
-        $pageSetupPath = $generation1->getUnparsedLoadedData()['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
+        $pageSetupPath = $unparsedLoadedData['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
         self::assertSame('xl/printerSettings/printerSettings1.bin', $pageSetupPath);
 
         $generation2Name = File::temporaryFilename();
@@ -39,9 +42,12 @@ class Issue3126Test extends TestCase
         self::assertCount(1, $gen2Images);
         $gen2hfName = array_key_exists('LF', $gen2Images) ? $gen2Images['LF']->getName() : '';
         self::assertSame('fleche-verte-up-right', $gen2hfName);
-        $pageSetupRel = $generation2->getUnparsedLoadedData()['sheets']['Worksheet']['pageSetupRelId'] ?? '';
+        /** @var mixed[][][][][] */
+        $unparsedLoadedData = $generation2->getUnparsedLoadedData();
+        /** @var string */
+        $pageSetupRel = $unparsedLoadedData['sheets']['Worksheet']['pageSetupRelId'] ?? '';
         self::assertSame('rId1ps', $pageSetupRel);
-        $pageSetupPath = $generation2->getUnparsedLoadedData()['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
+        $pageSetupPath = $unparsedLoadedData['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
         self::assertSame('xl/printerSettings/printerSettings1.bin', $pageSetupPath);
 
         $generation3Name = File::temporaryFilename();
@@ -56,9 +62,12 @@ class Issue3126Test extends TestCase
         self::assertCount(1, $gen3Images);
         $gen3hfName = array_key_exists('LF', $gen3Images) ? $gen3Images['LF']->getName() : '';
         self::assertSame('fleche-verte-up-right', $gen3hfName);
-        $pageSetupRel = $generation3->getUnparsedLoadedData()['sheets']['Worksheet']['pageSetupRelId'] ?? '';
+        /** @var mixed[][][][][] */
+        $unparsedLoadedData = $generation3->getUnparsedLoadedData();
+        /** @var string */
+        $pageSetupRel = $unparsedLoadedData['sheets']['Worksheet']['pageSetupRelId'] ?? '';
         self::assertSame('rId1ps', $pageSetupRel);
-        $pageSetupPath = $generation3->getUnparsedLoadedData()['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
+        $pageSetupPath = $unparsedLoadedData['sheets']['Worksheet']['printerSettings'][substr($pageSetupRel, 3)]['filePath'] ?? '';
         self::assertSame('xl/printerSettings/printerSettings1.bin', $pageSetupPath);
 
         unlink($generation2Name);
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3679ImgTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3679ImgTest.php
index 5c9b38074..ad4937923 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3679ImgTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3679ImgTest.php
@@ -6,6 +6,7 @@ namespace PhpOffice\PhpSpreadsheetTests\Reader\Xlsx;
 
 use PhpOffice\PhpSpreadsheet\Reader\Xlsx;
 use PhpOffice\PhpSpreadsheetTests\Functional\AbstractFunctional;
+use SimpleXMLElement;
 
 class Issue3679ImgTest extends AbstractFunctional
 {
@@ -23,6 +24,7 @@ class Issue3679ImgTest extends AbstractFunctional
         if ($drawings[0] === null) {
             self::fail('Unexpected null drawing');
         } else {
+            /** @var SimpleXMLElement */
             $srcRect = $drawings[0]->getSrcRect();
             self::assertSame('448', (string) ($srcRect['r'] ?? ''));
             self::assertSame('65769', (string) ($srcRect['b'] ?? ''));
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/LoadSheetsOnlyTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/LoadSheetsOnlyTest.php
index 5c70a7521..92f0cd53c 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/LoadSheetsOnlyTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/LoadSheetsOnlyTest.php
@@ -30,9 +30,9 @@ class LoadSheetsOnlyTest extends TestCase
         //$reader->setLoadSheetsOnly(['Sheet1']);
         $names = $reader->listWorksheetNames($filename);
         $reader->setLoadSheetsOnly([$names[0]]);
-        $this->spreadsheet = $reader->load($filename);
-        self::assertSame(1, $this->spreadsheet->getSheetCount());
-        self::assertSame('Sheet1', $this->spreadsheet->getActiveSheet()->getTitle());
+        $spreadsheet = $this->spreadsheet = $reader->load($filename);
+        self::assertSame(1, $spreadsheet->getSheetCount());
+        self::assertSame('Sheet1', $spreadsheet->getActiveSheet()->getTitle());
     }
 
     public function testLoadSheet2Only(): void
@@ -40,9 +40,9 @@ class LoadSheetsOnlyTest extends TestCase
         $filename = self::$testbook;
         $reader = new Xlsx();
         $reader->setLoadSheetsOnly(['Sheet2']);
-        $this->spreadsheet = $reader->load($filename);
-        self::assertSame(1, $this->spreadsheet->getSheetCount());
-        self::assertSame('Sheet2', $this->spreadsheet->getActiveSheet()->getTitle());
+        $spreadsheet = $this->spreadsheet = $reader->load($filename);
+        self::assertSame(1, $spreadsheet->getSheetCount());
+        self::assertSame('Sheet2', $spreadsheet->getActiveSheet()->getTitle());
     }
 
     public function testLoadNoSheet(): void
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/PageSetupTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/PageSetupTest.php
index 763dcfb07..bac85dbce 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/PageSetupTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/PageSetupTest.php
@@ -67,6 +67,7 @@ class PageSetupTest extends TestCase
         $spreadsheet->disconnectWorksheets();
     }
 
+    /** @return array<array{orientation: string, scale: int, horizontalCentered: bool, verticalCentered: bool, pageOrder: string}> */
     private function pageSetupAssertions(): array
     {
         return [
@@ -102,6 +103,7 @@ class PageSetupTest extends TestCase
         ];
     }
 
+    /** @return array<array{top: float, header: float, left: float, right: float, bottom: float, footer: float}> */
     private function pageMarginAssertions(): array
     {
         return [
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/SheetProtectionTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/SheetProtectionTest.php
index 123b39eb3..870f5bc8d 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/SheetProtectionTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/SheetProtectionTest.php
@@ -43,6 +43,7 @@ class SheetProtectionTest extends AbstractFunctional
         $spreadsheet->disconnectWorksheets();
     }
 
+    /** @return array<array{sheet: ?bool, autoFilter: ?bool, formatCells: ?bool, formatColumns: ?bool, formatRows: ?bool, insertColumns: ?bool, insertHyperlinks: ?bool, insertRows: ?bool, deleteColumns: ?bool, deleteRows: ?bool, objects: ?bool, pivotTables: ?bool, scenarios: ?bool, selectLockedCells: ?bool, selectUnlockedCells: ?bool, sort: ?bool, algorithm: string, spinCount: int}> */
     private function pageSetupAssertions(): array
     {
         return [
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/XlsxTest.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/XlsxTest.php
index 7ce2ca7c1..bf8644f72 100644
--- a/tests/PhpSpreadsheetTests/Reader/Xlsx/XlsxTest.php
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/XlsxTest.php
@@ -166,7 +166,9 @@ class XlsxTest extends TestCase
         self::assertEquals(Conditional::CONDITION_CELLIS, $conditionalRule->getConditionType());
         self::assertEquals(Conditional::OPERATOR_BETWEEN, $conditionalRule->getOperatorType());
         self::assertEquals(['200', '400'], $conditionalRule->getConditions());
-        self::assertSame('#,##0.00_-"€"', $conditionalRule->getStyle()->exportArray()['numberFormat']['formatCode']);
+        /** @var mixed[][] */
+        $temp = $conditionalRule->getStyle()->exportArray();
+        self::assertSame('#,##0.00_-"€"', $temp['numberFormat']['formatCode']);
         $spreadsheet->disconnectWorksheets();
     }
 
diff --git a/tests/PhpSpreadsheetTests/Shared/Date2Test.php b/tests/PhpSpreadsheetTests/Shared/Date2Test.php
index c109e0279..97eea7933 100644
--- a/tests/PhpSpreadsheetTests/Shared/Date2Test.php
+++ b/tests/PhpSpreadsheetTests/Shared/Date2Test.php
@@ -8,6 +8,7 @@ use PhpOffice\PhpSpreadsheet\Calculation\Exception as CalculationException;
 use PhpOffice\PhpSpreadsheet\Cell\Cell;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
 use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 class Date2Test extends TestCase
@@ -37,24 +38,26 @@ class Date2Test extends TestCase
         Cell::setCalculateDateTimeType(-1);
     }
 
-    #[\PHPUnit\Framework\Attributes\DataProvider('providerTimeOnly')]
+    #[DataProvider('providerTimeOnly')]
     public function testTimeOnly(int|float $expectedResult, int|float|string $value, ?string $format = null): void
     {
         Cell::setCalculateDateTimeType(Cell::CALCULATE_TIME_FLOAT);
-        $this->spreadsheet = new Spreadsheet();
-        self::assertSame(0, $this->spreadsheet->getActiveSheetIndex());
-        $sheet = $this->spreadsheet->getActiveSheet();
-        $newSheet = $this->spreadsheet->createSheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        self::assertSame(0, $spreadsheet->getActiveSheetIndex());
+        $sheet = $spreadsheet->getActiveSheet();
+        $newSheet = $spreadsheet->createSheet();
         $newSheet->getCell('B7')->setValue('Here');
         $sheet->getCell('A1')->setValue($value);
         if ($format !== null) {
-            $sheet->getStyle('A1')->getNumberFormat()->setFormatCode($format);
+            $sheet->getStyle('A1')
+                ->getNumberFormat()
+                ->setFormatCode($format);
         }
         $sheet->setSelectedCells('B7');
-        $this->spreadsheet->setActiveSheetIndex(1);
+        $spreadsheet->setActiveSheetIndex(1);
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
         self::assertSame('B7', $sheet->getSelectedCells());
-        self::assertSame(1, $this->spreadsheet->getActiveSheetIndex());
+        self::assertSame(1, $spreadsheet->getActiveSheetIndex());
     }
 
     public static function providerTimeOnly(): array
@@ -80,24 +83,28 @@ class Date2Test extends TestCase
         ];
     }
 
-    #[\PHPUnit\Framework\Attributes\DataProvider('providerDateAndTime')]
+    #[DataProvider('providerDateAndTime')]
     public function testDateAndTime(int|float $expectedResult, int|float|string $value, ?string $format = null): void
     {
-        Cell::setCalculateDateTimeType(Cell::CALCULATE_DATE_TIME_FLOAT);
-        $this->spreadsheet = new Spreadsheet();
-        self::assertSame(0, $this->spreadsheet->getActiveSheetIndex());
-        $sheet = $this->spreadsheet->getActiveSheet();
-        $newSheet = $this->spreadsheet->createSheet();
+        Cell::setCalculateDateTimeType(
+            Cell::CALCULATE_DATE_TIME_FLOAT
+        );
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        self::assertSame(0, $spreadsheet->getActiveSheetIndex());
+        $sheet = $spreadsheet->getActiveSheet();
+        $newSheet = $spreadsheet->createSheet();
         $newSheet->getCell('B7')->setValue('Here');
         $sheet->getCell('A1')->setValue($value);
         if ($format !== null) {
-            $sheet->getStyle('A1')->getNumberFormat()->setFormatCode($format);
+            $sheet->getStyle('A1')
+                ->getNumberFormat()
+                ->setFormatCode($format);
         }
         $sheet->setSelectedCells('B7');
-        $this->spreadsheet->setActiveSheetIndex(1);
+        $spreadsheet->setActiveSheetIndex(1);
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
         self::assertSame('B7', $sheet->getSelectedCells());
-        self::assertSame(1, $this->spreadsheet->getActiveSheetIndex());
+        self::assertSame(1, $spreadsheet->getActiveSheetIndex());
     }
 
     public static function providerDateAndTime(): array
@@ -123,44 +130,49 @@ class Date2Test extends TestCase
         ];
     }
 
-    #[\PHPUnit\Framework\Attributes\DataProvider('providerAsis')]
+    #[DataProvider('providerAsis')]
     public function testDefault(int|float $expectedResult, int|float|string $value, ?string $format = null): void
     {
-        //Cell::setCalculateDateTimeType(Cell::CALCULATE_DATE_TIME_ASIS);
-        $this->spreadsheet = new Spreadsheet();
-        self::assertSame(0, $this->spreadsheet->getActiveSheetIndex());
-        $sheet = $this->spreadsheet->getActiveSheet();
-        $newSheet = $this->spreadsheet->createSheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        self::assertSame(0, $spreadsheet->getActiveSheetIndex());
+        $sheet = $spreadsheet->getActiveSheet();
+        $newSheet = $spreadsheet->createSheet();
         $newSheet->getCell('B7')->setValue('Here');
         $sheet->getCell('A1')->setValue($value);
         if ($format !== null) {
-            $sheet->getStyle('A1')->getNumberFormat()->setFormatCode($format);
+            $sheet->getStyle('A1')
+                ->getNumberFormat()
+                ->setFormatCode($format);
         }
         $sheet->setSelectedCells('B7');
-        $this->spreadsheet->setActiveSheetIndex(1);
+        $spreadsheet->setActiveSheetIndex(1);
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
         self::assertSame('B7', $sheet->getSelectedCells());
-        self::assertSame(1, $this->spreadsheet->getActiveSheetIndex());
+        self::assertSame(1, $spreadsheet->getActiveSheetIndex());
     }
 
-    #[\PHPUnit\Framework\Attributes\DataProvider('providerAsis')]
+    #[DataProvider('providerAsis')]
     public function testAsis(int|float $expectedResult, int|float|string $value, ?string $format = null): void
     {
-        Cell::setCalculateDateTimeType(Cell::CALCULATE_DATE_TIME_ASIS);
-        $this->spreadsheet = new Spreadsheet();
-        self::assertSame(0, $this->spreadsheet->getActiveSheetIndex());
-        $sheet = $this->spreadsheet->getActiveSheet();
-        $newSheet = $this->spreadsheet->createSheet();
+        Cell::setCalculateDateTimeType(
+            Cell::CALCULATE_DATE_TIME_ASIS
+        );
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        self::assertSame(0, $spreadsheet->getActiveSheetIndex());
+        $sheet = $spreadsheet->getActiveSheet();
+        $newSheet = $spreadsheet->createSheet();
         $newSheet->getCell('B7')->setValue('Here');
         $sheet->getCell('A1')->setValue($value);
         if ($format !== null) {
-            $sheet->getStyle('A1')->getNumberFormat()->setFormatCode($format);
+            $sheet->getStyle('A1')
+                ->getNumberFormat()
+                ->setFormatCode($format);
         }
         $sheet->setSelectedCells('B7');
-        $this->spreadsheet->setActiveSheetIndex(1);
+        $spreadsheet->setActiveSheetIndex(1);
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
         self::assertSame('B7', $sheet->getSelectedCells());
-        self::assertSame(1, $this->spreadsheet->getActiveSheetIndex());
+        self::assertSame(1, $spreadsheet->getActiveSheetIndex());
     }
 
     public static function providerAsis(): array
diff --git a/tests/PhpSpreadsheetTests/Shared/StringHelperLocaleTest.php b/tests/PhpSpreadsheetTests/Shared/StringHelperLocaleTest.php
index c4178f53a..d3c0b43df 100644
--- a/tests/PhpSpreadsheetTests/Shared/StringHelperLocaleTest.php
+++ b/tests/PhpSpreadsheetTests/Shared/StringHelperLocaleTest.php
@@ -32,12 +32,13 @@ class StringHelperLocaleTest extends TestCase
 
     public function testCurrency(): void
     {
+        $currentLocale = ($this->currentLocale === false) ? null : $this->currentLocale;
         if ($this->currentLocale === false || !setlocale(LC_ALL, 'de_DE.UTF-8', 'deu_deu.utf8')) {
             self::markTestSkipped('Unable to set German UTF8 locale for testing.');
         }
         $result = StringHelper::getCurrencyCode();
         self::assertSame('€', $result);
-        if (!setlocale(LC_ALL, $this->currentLocale)) {
+        if (!setlocale(LC_ALL, $currentLocale)) {
             self::markTestSkipped('Unable to restore default locale.');
         }
         $result = StringHelper::getCurrencyCode();
diff --git a/tests/PhpSpreadsheetTests/SpreadsheetCopyCloneTest.php b/tests/PhpSpreadsheetTests/SpreadsheetCopyCloneTest.php
index f45ed9385..1752230aa 100644
--- a/tests/PhpSpreadsheetTests/SpreadsheetCopyCloneTest.php
+++ b/tests/PhpSpreadsheetTests/SpreadsheetCopyCloneTest.php
@@ -29,8 +29,8 @@ class SpreadsheetCopyCloneTest extends TestCase
     #[DataProvider('providerCopyClone')]
     public function testCopyClone(string $type): void
     {
-        $this->spreadsheet = new Spreadsheet();
-        $sheet = $this->spreadsheet->getActiveSheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $sheet = $spreadsheet->getActiveSheet();
         $sheet->setTitle('original');
         $sheet->getStyle('A1')->getFont()->setName('font1');
         $sheet->getStyle('A2')->getFont()->setName('font2');
@@ -45,14 +45,14 @@ class SpreadsheetCopyCloneTest extends TestCase
         self::assertSame('font1', $sheet->getStyle('A1')->getFont()->getName());
         $sheet->setSelectedCells('A3');
         if ($type === 'copy') {
-            $this->spreadsheet2 = $this->spreadsheet->copy();
+            $spreadsheet2 = $this->spreadsheet2 = $spreadsheet->copy();
         } else {
-            $this->spreadsheet2 = clone $this->spreadsheet;
+            $spreadsheet2 = $this->spreadsheet2 = clone $spreadsheet;
         }
-        self::assertSame($this->spreadsheet, $this->spreadsheet->getCalculationEngine()?->getSpreadsheet());
-        self::assertSame($this->spreadsheet2, $this->spreadsheet2->getCalculationEngine()?->getSpreadsheet());
+        self::assertSame($spreadsheet, $spreadsheet->getCalculationEngine()?->getSpreadsheet());
+        self::assertSame($spreadsheet2, $spreadsheet2->getCalculationEngine()?->getSpreadsheet());
         self::assertSame('A3', $sheet->getSelectedCells());
-        $copysheet = $this->spreadsheet2->getActiveSheet();
+        $copysheet = $spreadsheet2->getActiveSheet();
         self::assertSame('A3', $copysheet->getSelectedCells());
         self::assertSame('original', $copysheet->getTitle());
         $copysheet->setTitle('unoriginal');
@@ -130,19 +130,19 @@ class SpreadsheetCopyCloneTest extends TestCase
     #[DataProvider('providerCopyClone2')]
     public function testCopyClone2(string $type, bool $suppress, bool $cache, bool $pruning, string $return): void
     {
-        $this->spreadsheet = new Spreadsheet();
-        $calc = $this->spreadsheet->getCalculationEngine();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $calc = $spreadsheet->getCalculationEngine();
         self::assertNotNull($calc);
         $calc->setSuppressFormulaErrors($suppress);
         $calc->setCalculationCacheEnabled($cache);
         $calc->setBranchPruningEnabled($pruning);
         $calc->setInstanceArrayReturnType($return);
         if ($type === 'copy') {
-            $this->spreadsheet2 = $this->spreadsheet->copy();
+            $spreadsheet2 = $this->spreadsheet2 = $spreadsheet->copy();
         } else {
-            $this->spreadsheet2 = clone $this->spreadsheet;
+            $spreadsheet2 = $this->spreadsheet2 = clone $spreadsheet;
         }
-        $calc2 = $this->spreadsheet2->getCalculationEngine();
+        $calc2 = $spreadsheet2->getCalculationEngine();
         self::assertNotNull($calc2);
         self::assertSame($suppress, $calc2->getSuppressFormulaErrors());
         self::assertSame($cache, $calc2->getCalculationCacheEnabled());
diff --git a/tests/PhpSpreadsheetTests/SpreadsheetCoverageTest.php b/tests/PhpSpreadsheetTests/SpreadsheetCoverageTest.php
index 3071e1297..338ddd60a 100644
--- a/tests/PhpSpreadsheetTests/SpreadsheetCoverageTest.php
+++ b/tests/PhpSpreadsheetTests/SpreadsheetCoverageTest.php
@@ -32,50 +32,50 @@ class SpreadsheetCoverageTest extends TestCase
         $properties = $this->spreadsheet->getProperties();
         $properties->setCreator('Anyone');
         $properties->setTitle('Description');
-        $this->spreadsheet2 = new Spreadsheet();
+        $spreadsheet2 = $this->spreadsheet2 = new Spreadsheet();
         self::assertNotEquals($properties, $this->spreadsheet2->getProperties());
         $properties2 = clone $properties;
-        $this->spreadsheet2->setProperties($properties2);
-        self::assertEquals($properties, $this->spreadsheet2->getProperties());
+        $spreadsheet2->setProperties($properties2);
+        self::assertEquals($properties, $spreadsheet2->getProperties());
     }
 
     public function testDocumentSecurity(): void
     {
-        $this->spreadsheet = new Spreadsheet();
-        $security = $this->spreadsheet->getSecurity();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $security = $spreadsheet->getSecurity();
         $security->setLockRevision(true);
         $revisionsPassword = 'revpasswd';
         $security->setRevisionsPassword($revisionsPassword);
-        $this->spreadsheet2 = new Spreadsheet();
-        self::assertNotEquals($security, $this->spreadsheet2->getSecurity());
+        $spreadsheet2 = $this->spreadsheet2 = new Spreadsheet();
+        self::assertNotEquals($security, $spreadsheet2->getSecurity());
         $security2 = clone $security;
-        $this->spreadsheet2->setSecurity($security2);
-        self::assertEquals($security, $this->spreadsheet2->getSecurity());
+        $spreadsheet2->setSecurity($security2);
+        self::assertEquals($security, $spreadsheet2->getSecurity());
     }
 
     public function testCellXfCollection(): void
     {
-        $this->spreadsheet = new Spreadsheet();
-        $sheet = $this->spreadsheet->getActiveSheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $sheet = $spreadsheet->getActiveSheet();
         $sheet->getStyle('A1')->getFont()->setName('font1');
         $sheet->getStyle('A2')->getFont()->setName('font2');
         $sheet->getStyle('A3')->getFont()->setName('font3');
         $sheet->getStyle('B1')->getFont()->setName('font1');
         $sheet->getStyle('B2')->getFont()->setName('font2');
-        $collection = $this->spreadsheet->getCellXfCollection();
+        $collection = $spreadsheet->getCellXfCollection();
         self::assertCount(4, $collection);
         $font1Style = $collection[1];
-        self::assertTrue($this->spreadsheet->cellXfExists($font1Style));
-        self::assertSame('font1', $this->spreadsheet->getCellXfCollection()[1]->getFont()->getName());
+        self::assertTrue($spreadsheet->cellXfExists($font1Style));
+        self::assertSame('font1', $spreadsheet->getCellXfCollection()[1]->getFont()->getName());
         self::assertSame('font1', $sheet->getStyle('A1')->getFont()->getName());
         self::assertSame('font2', $sheet->getStyle('A2')->getFont()->getName());
         self::assertSame('font3', $sheet->getStyle('A3')->getFont()->getName());
         self::assertSame('font1', $sheet->getStyle('B1')->getFont()->getName());
         self::assertSame('font2', $sheet->getStyle('B2')->getFont()->getName());
 
-        $this->spreadsheet->removeCellXfByIndex(1);
-        self::assertFalse($this->spreadsheet->cellXfExists($font1Style));
-        self::assertSame('font2', $this->spreadsheet->getCellXfCollection()[1]->getFont()->getName());
+        $spreadsheet->removeCellXfByIndex(1);
+        self::assertFalse($spreadsheet->cellXfExists($font1Style));
+        self::assertSame('font2', $spreadsheet->getCellXfCollection()[1]->getFont()->getName());
         self::assertSame('Calibri', $sheet->getStyle('A1')->getFont()->getName());
         self::assertSame('font2', $sheet->getStyle('A2')->getFont()->getName());
         self::assertSame('font3', $sheet->getStyle('A3')->getFont()->getName());
@@ -109,14 +109,14 @@ class SpreadsheetCoverageTest extends TestCase
 
     public function testCellStyleXF(): void
     {
-        $this->spreadsheet = new Spreadsheet();
-        $collection = $this->spreadsheet->getCellStyleXfCollection();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $collection = $spreadsheet->getCellStyleXfCollection();
         self::assertCount(1, $collection);
         $styleXf = $collection[0];
-        self::assertSame($styleXf, $this->spreadsheet->getCellStyleXfByIndex(0));
+        self::assertSame($styleXf, $spreadsheet->getCellStyleXfByIndex(0));
         $hash = $styleXf->getHashCode();
-        self::assertSame($styleXf, $this->spreadsheet->getCellStyleXfByHashCode($hash));
-        self::assertFalse($this->spreadsheet->getCellStyleXfByHashCode($hash . 'x'));
+        self::assertSame($styleXf, $spreadsheet->getCellStyleXfByHashCode($hash));
+        self::assertFalse($spreadsheet->getCellStyleXfByHashCode($hash . 'x'));
     }
 
     public function testInvalidRemoveCellStyleXfByIndex(): void
@@ -139,12 +139,13 @@ class SpreadsheetCoverageTest extends TestCase
     {
         $this->expectException(SSException::class);
         $this->expectExceptionMessage('Invalid visibility value.');
-        $this->spreadsheet = new Spreadsheet();
-        $this->spreadsheet->setVisibility(Spreadsheet::VISIBILITY_HIDDEN);
-        self::assertSame(Spreadsheet::VISIBILITY_HIDDEN, $this->spreadsheet->getVisibility());
-        $this->spreadsheet->setVisibility(null);
-        self::assertSame(Spreadsheet::VISIBILITY_VISIBLE, $this->spreadsheet->getVisibility());
-        $this->spreadsheet->setVisibility('badvalue');
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $spreadsheet
+            ->setVisibility(Spreadsheet::VISIBILITY_HIDDEN);
+        self::assertSame(Spreadsheet::VISIBILITY_HIDDEN, $spreadsheet->getVisibility());
+        $spreadsheet->setVisibility(null);
+        self::assertSame(Spreadsheet::VISIBILITY_VISIBLE, $spreadsheet->getVisibility());
+        $spreadsheet->setVisibility('badvalue');
     }
 
     public function testInvalidTabRatio(): void
diff --git a/tests/PhpSpreadsheetTests/SpreadsheetDuplicateSheetTest.php b/tests/PhpSpreadsheetTests/SpreadsheetDuplicateSheetTest.php
index b84026700..f7b033233 100644
--- a/tests/PhpSpreadsheetTests/SpreadsheetDuplicateSheetTest.php
+++ b/tests/PhpSpreadsheetTests/SpreadsheetDuplicateSheetTest.php
@@ -21,7 +21,7 @@ class SpreadsheetDuplicateSheetTest extends TestCase
 
     public function testDuplicate(): void
     {
-        $this->spreadsheet = new Spreadsheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
         $sheet = $this->spreadsheet->getActiveSheet();
         $sheet->setTitle('original');
         $sheet->getCell('A1')->setValue('text1');
@@ -50,7 +50,7 @@ class SpreadsheetDuplicateSheetTest extends TestCase
             $newSheet->getStyle('A2')->getFont()->getBold()
         );
         $sheetNames = [];
-        foreach ($this->spreadsheet->getWorksheetIterator() as $worksheet) {
+        foreach ($spreadsheet->getWorksheetIterator() as $worksheet) {
             $sheetNames[] = $worksheet->getTitle();
         }
         $expected = ['original', 'original 1', 'added', 'added 1'];
diff --git a/tests/PhpSpreadsheetTests/Style/FontTest.php b/tests/PhpSpreadsheetTests/Style/FontTest.php
index 20df75b1a..389454527 100644
--- a/tests/PhpSpreadsheetTests/Style/FontTest.php
+++ b/tests/PhpSpreadsheetTests/Style/FontTest.php
@@ -102,6 +102,7 @@ class FontTest extends TestCase
             [
                 'type' => 'srgbClr',
                 'value' => 'FF0000',
+                'alpha' => null,
             ]
         );
         $font2bHash = $font2->getHashCode();
diff --git a/tests/PhpSpreadsheetTests/Writer/Xlsx/CalculationErrorTest.php b/tests/PhpSpreadsheetTests/Writer/Xlsx/CalculationErrorTest.php
index 8a22768ff..1bb4fc0c9 100644
--- a/tests/PhpSpreadsheetTests/Writer/Xlsx/CalculationErrorTest.php
+++ b/tests/PhpSpreadsheetTests/Writer/Xlsx/CalculationErrorTest.php
@@ -29,18 +29,18 @@ class CalculationErrorTest extends AbstractFunctional
 
     public function testCalculationExceptionSuppressed(): void
     {
-        $this->spreadsheet = new Spreadsheet();
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
         $sheet = $this->spreadsheet->getActiveSheet();
-        $calculation = Calculation::getInstance($this->spreadsheet);
+        $calculation = Calculation::getInstance($spreadsheet);
         self::assertFalse($calculation->getSuppressFormulaErrors());
         $calculation->setSuppressFormulaErrors(true);
         $sheet->getCell('A1')->setValue('=SUM(');
         $sheet->getCell('A2')->setValue('=2+3');
-        $this->reloadedSpreadsheet = $this->writeAndReload($this->spreadsheet, 'Xlsx');
+        $spreadsheet2 = $this->reloadedSpreadsheet = $this->writeAndReload($spreadsheet, 'Xlsx');
         $rcalculation = Calculation::getInstance($this->reloadedSpreadsheet);
         self::assertFalse($rcalculation->getSuppressFormulaErrors());
         $rcalculation->setSuppressFormulaErrors(true);
-        $rsheet = $this->reloadedSpreadsheet->getActiveSheet();
+        $rsheet = $spreadsheet2->getActiveSheet();
         self::assertSame('=SUM(', $rsheet->getCell('A1')->getValue());
         self::assertFalse($rsheet->getCell('A1')->getCalculatedValue());
         self::assertSame('=2+3', $rsheet->getCell('A2')->getValue());
@@ -53,12 +53,12 @@ class CalculationErrorTest extends AbstractFunctional
     {
         $this->expectException(CalcException::class);
         $this->expectExceptionMessage("Formula Error: Expecting ')'");
-        $this->spreadsheet = new Spreadsheet();
-        $sheet = $this->spreadsheet->getActiveSheet();
-        $calculation = Calculation::getInstance($this->spreadsheet);
+        $spreadsheet = $this->spreadsheet = new Spreadsheet();
+        $sheet = $spreadsheet->getActiveSheet();
+        $calculation = Calculation::getInstance($spreadsheet);
         self::assertFalse($calculation->getSuppressFormulaErrors());
         $sheet->getCell('A1')->setValue('=SUM(');
         $sheet->getCell('A2')->setValue('=2+3');
-        $this->reloadedSpreadsheet = $this->writeAndReload($this->spreadsheet, 'Xlsx');
+        $this->reloadedSpreadsheet = $this->writeAndReload($spreadsheet, 'Xlsx');
     }
 }
diff --git a/tests/data/Reader/XLS/pwtest.xls b/tests/data/Reader/XLS/pwtest.xls
new file mode 100644
index 000000000..a82e0f6fe
Binary files /dev/null and b/tests/data/Reader/XLS/pwtest.xls differ
diff --git a/tests/data/Reader/XLS/pwtest2.xls b/tests/data/Reader/XLS/pwtest2.xls
new file mode 100644
index 000000000..76b4bd342
Binary files /dev/null and b/tests/data/Reader/XLS/pwtest2.xls differ
diff --git a/tests/data/Reader/XLS/pwtest3.xls b/tests/data/Reader/XLS/pwtest3.xls
new file mode 100644
index 000000000..1038052c2
Binary files /dev/null and b/tests/data/Reader/XLS/pwtest3.xls differ