Lock our deps with our minimum PHP 7.2, instead of PHP 7.3

phpstan-baseline.neon

@@ -35,11 +35,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/Calculation.php
 
-		-
-			message: "#^Binary operation \"\\-\" between 0 and string\\|false results in an error\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/Calculation.php
-
 		-
 			message: "#^Property PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\Calculation\\:\\:\\$spreadsheet \\(PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\) does not accept PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|null\\.$#"
 			count: 1
@@ -425,11 +420,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/Engineering/Erf.php
 
-		-
-			message: "#^Binary operation \"\\-\" between 1 and float\\|string results in an error\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/Engineering/Erf.php
-
 		-
 			message: "#^Property PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\Engineering\\\\ErfC\\:\\:\\$oneSqrtPi has no typehint specified\\.$#"
 			count: 1
@@ -445,11 +435,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/Engineering/ErfC.php
 
-		-
-			message: "#^Binary operation \"\\-\" between 2 and float\\|string results in an error\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/Engineering/ErfC.php
-
 		-
 			message: "#^Parameter \\#1 \\$callback of function set_error_handler expects \\(callable\\(int, string, string, int, array\\)\\: bool\\)\\|null, array\\('PhpOffice\\\\\\\\PhpSpreadsheet\\\\\\\\Calculation\\\\\\\\Exception', 'errorHandlerCallback'\\) given\\.$#"
 			count: 1
@@ -675,11 +660,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/LookupRef/Address.php
 
-		-
-			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\LookupRef\\\\ExcelMatch\\:\\:MATCH\\(\\) should return int\\|string but returns float\\|int\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/LookupRef/ExcelMatch.php
-
 		-
 			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\LookupRef\\\\ExcelMatch\\:\\:matchFirstValue\\(\\) has no return typehint specified\\.$#"
 			count: 1
@@ -1005,11 +985,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/Statistical/Distributions/Beta.php
 
-		-
-			message: "#^Binary operation \"\\-\" between 1 and float\\|string results in an error\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/Statistical/Distributions/ChiSquared.php
-
 		-
 			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Calculation\\\\Statistical\\\\Distributions\\\\ChiSquared\\:\\:pchisq\\(\\) has no return typehint specified\\.$#"
 			count: 1
@@ -1130,11 +1105,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Calculation/Statistical/Distributions/NewtonRaphson.php
 
-		-
-			message: "#^Binary operation \"\\-\" between 1 and float\\|string results in an error\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Calculation/Statistical/Distributions/StandardNormal.php
-
 		-
 			message: "#^Binary operation \"\\-\" between float\\|string and float\\|int\\|\\(string&numeric\\) results in an error\\.$#"
 			count: 1
@@ -2355,16 +2325,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Reader/Xls.php
 
-		-
-			message: "#^Parameter \\#1 \\$pValue of method PhpOffice\\\\PhpSpreadsheet\\\\Worksheet\\\\BaseDrawing\\:\\:setOffsetX\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Reader/Xls.php
-
-		-
-			message: "#^Parameter \\#1 \\$pValue of method PhpOffice\\\\PhpSpreadsheet\\\\Worksheet\\\\BaseDrawing\\:\\:setOffsetY\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Reader/Xls.php
-
 		-
 			message: "#^Parameter \\#2 \\$row of method PhpOffice\\\\PhpSpreadsheet\\\\Reader\\\\IReadFilter\\:\\:readCell\\(\\) expects int, string given\\.$#"
 			count: 1
@@ -2400,21 +2360,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Reader/Xls.php
 
-		-
-			message: "#^Parameter \\#2 \\$pos of static method PhpOffice\\\\PhpSpreadsheet\\\\Reader\\\\Xls\\:\\:getUInt2d\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Reader/Xls.php
-
-		-
-			message: "#^Parameter \\#2 \\$pos of static method PhpOffice\\\\PhpSpreadsheet\\\\Reader\\\\Xls\\:\\:getInt4d\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Reader/Xls.php
-
-		-
-			message: "#^Parameter \\#2 \\$start of function substr expects int, float\\|int given\\.$#"
-			count: 5
-			path: src/PhpSpreadsheet/Reader/Xls.php
-
 		-
 			message: "#^Parameter \\#1 \\$pValue of method PhpOffice\\\\PhpSpreadsheet\\\\Worksheet\\\\Worksheet\\:\\:setShowSummaryBelow\\(\\) expects bool, int given\\.$#"
 			count: 1
@@ -2610,11 +2555,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Reader/Xlsx.php
 
-		-
-			message: "#^Parameter \\#1 \\$is of method PhpOffice\\\\PhpSpreadsheet\\\\Reader\\\\Xlsx\\:\\:parseRichText\\(\\) expects SimpleXMLElement\\|null, object given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Reader/Xlsx.php
-
 		-
 			message: "#^Negated boolean expression is always true\\.$#"
 			count: 1
@@ -3336,12 +3276,12 @@ parameters:
 			path: src/PhpSpreadsheet/Reader/Xml.php
 
 		-
-			message: "#^Parameter \\#2 \\$cmp_function of function uksort expects callable\\(mixed, mixed\\)\\: int, array\\('self', 'cellReverseSort'\\) given\\.$#"
+			message: "#^Parameter \\#2 \\$cmp_function of function uksort expects callable\\(\\(int\\|string\\), \\(int\\|string\\)\\)\\: int, array\\('self', 'cellReverseSort'\\) given\\.$#"
 			count: 4
 			path: src/PhpSpreadsheet/ReferenceHelper.php
 
 		-
-			message: "#^Parameter \\#2 \\$cmp_function of function uksort expects callable\\(mixed, mixed\\)\\: int, array\\('self', 'cellSort'\\) given\\.$#"
+			message: "#^Parameter \\#2 \\$cmp_function of function uksort expects callable\\(\\(int\\|string\\), \\(int\\|string\\)\\)\\: int, array\\('self', 'cellSort'\\) given\\.$#"
 			count: 4
 			path: src/PhpSpreadsheet/ReferenceHelper.php
 
@@ -3350,11 +3290,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/ReferenceHelper.php
 
-		-
-			message: "#^Parameter \\#1 \\$columnIndex of static method PhpOffice\\\\PhpSpreadsheet\\\\Cell\\\\Coordinate\\:\\:stringFromColumnIndex\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/ReferenceHelper.php
-
 		-
 			message: "#^Parameter \\#3 \\$subject of function str_replace expects array\\|string, string\\|null given\\.$#"
 			count: 1
@@ -5330,11 +5265,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Writer/Xls.php
 
-		-
-			message: "#^Parameter \\#2 \\$pad_length of function str_pad expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Writer/Xls.php
-
 		-
 			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Writer\\\\Xls\\\\BIFFwriter\\:\\:writeEof\\(\\) has no return typehint specified\\.$#"
 			count: 1
@@ -5870,16 +5800,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Writer/Xlsx/Rels.php
 
-		-
-			message: "#^Parameter \\#2 \\$pId of method PhpOffice\\\\PhpSpreadsheet\\\\Writer\\\\Xlsx\\\\Rels\\:\\:writeRelationship\\(\\) expects int, float\\|int given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Writer/Xlsx/Rels.php
-
-		-
-			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Writer\\\\Xlsx\\\\Rels\\:\\:writeDrawingHyperLink\\(\\) should return int but returns float\\|int\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Writer/Xlsx/Rels.php
-
 		-
 			message: "#^Parameter \\#2 \\$value of method XMLWriter\\:\\:writeAttribute\\(\\) expects string, int\\<0, max\\> given\\.$#"
 			count: 1
@@ -6380,16 +6300,6 @@ parameters:
 			count: 2
 			path: tests/PhpSpreadsheetTests/Writer/Xlsx/UnparsedDataTest.php
 
-		-
-			message: "#^Cannot access property \\$workbookProtection on SimpleXMLElement\\|false\\.$#"
-			count: 3
-			path: tests/PhpSpreadsheetTests/Writer/Xlsx/UnparsedDataTest.php
-
-		-
-			message: "#^Cannot access property \\$sheets on SimpleXMLElement\\|false\\.$#"
-			count: 2
-			path: tests/PhpSpreadsheetTests/Writer/Xlsx/UnparsedDataTest.php
-
 		-
 			message: "#^Cannot access property \\$pageSetup on SimpleXMLElement\\|false\\.$#"
 			count: 1
@@ -6400,3 +6310,53 @@ parameters:
 			count: 5
 			path: tests/PhpSpreadsheetTests/Writer/Xlsx/UnparsedDataTest.php
 
+		-
+			message: "#^Argument of an invalid type SimpleXMLElement\\|null supplied for foreach, only iterables are supported\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Reader/Xml/Properties.php
+
+		-
+			message: "#^Argument of an invalid type SimpleXMLElement\\|null supplied for foreach, only iterables are supported\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Reader/Xml/Style.php
+
+		-
+			message: "#^Binary operation \"/\" between int\\|string and 360 results in an error\\.$#"
+			count: 3
+			path: src/PhpSpreadsheet/Calculation/DateTimeExcel/YearFrac.php
+
+		-
+			message: "#^Binary operation \"/\" between int\\|string and 365 results in an error\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Calculation/DateTimeExcel/YearFrac.php
+
+		-
+			message: "#^Binary operation \"/\" between int\\|string and \\(float\\|int\\) results in an error\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Calculation/DateTimeExcel/YearFrac.php
+
+		-
+			message: "#^Binary operation \"/\" between float\\|string and float\\|string results in an error\\.$#"
+			count: 2
+			path: src/PhpSpreadsheet/Calculation/Financial/Securities/Price.php
+
+		-
+			message: "#^Binary operation \"/\" between float\\|int\\|string and float\\|int\\|string results in an error\\.$#"
+			count: 2
+			path: src/PhpSpreadsheet/Calculation/MathTrig/Combinations.php
+
+		-
+			message: "#^Binary operation \"/\" between float\\|int\\|string and float\\|int results in an error\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Calculation/MathTrig/Factorial.php
+
+		-
+			message: "#^Binary operation \"/\" between float\\|int\\|string and float\\|int\\|string results in an error\\.$#"
+			count: 1
+			path: src/PhpSpreadsheet/Calculation/Statistical/Permutations.php
+
+		-
+			message: "#^Offset '(percentage|value)' does not exist on SimpleXMLElement|null\\.$#"
+			count: 3
+			path: src/PhpSpreadsheet/Reader/Gnumeric/PageSetup.php
+

src/PhpSpreadsheet/Calculation/Calculation.php

@@ -3161,9 +3161,9 @@ class Calculation
         return $formula;
     }
 
-    private static $functionReplaceFromExcel = null;
+    private static $functionReplaceFromExcel;
 
-    private static $functionReplaceToLocale = null;
+    private static $functionReplaceToLocale;
 
     public function _translateFormulaToLocale($formula)
     {
@@ -3190,9 +3190,9 @@ class Calculation
         return self::translateFormula(self::$functionReplaceFromExcel, self::$functionReplaceToLocale, $formula, ',', self::$localeArgumentSeparator);
     }
 
-    private static $functionReplaceFromLocale = null;
+    private static $functionReplaceFromLocale;
 
-    private static $functionReplaceToExcel = null;
+    private static $functionReplaceToExcel;
 
     public function _translateFormulaToEnglish($formula)
     {
@@ -5405,7 +5405,7 @@ class Calculation
             // Apply any defaults for empty argument values
             foreach ($emptyArguments as $argumentId => $isArgumentEmpty) {
                 if ($isArgumentEmpty === true) {
-                    $reflectedArgumentId = count($args) - $argumentId - 1;
+                    $reflectedArgumentId = count($args) - (int) $argumentId - 1;
                     if (
                         !array_key_exists($reflectedArgumentId, $methodArguments) ||
                         $methodArguments[$reflectedArgumentId]->isVariadic()

src/PhpSpreadsheet/Calculation/Statistical/Deviations.php

@@ -103,7 +103,7 @@ class Deviations
      *
      * @param array ...$args Data Series
      *
-     * @return float|string The result, or a string containing an error
+     * @return float|int|string The result, or a string containing an error
      */
     public static function skew(...$args)
     {

src/PhpSpreadsheet/Reader/Gnumeric.php

@@ -209,7 +209,7 @@ class Gnumeric extends BaseReader
             foreach ($sheet->Objects->children(self::NAMESPACE_GNM) as $key => $comment) {
                 $commentAttributes = $comment->attributes();
                 //    Only comment objects are handled at the moment
-                if ($commentAttributes->Text) {
+                if ($commentAttributes && $commentAttributes->Text) {
                     $this->spreadsheet->getActiveSheet()->getComment((string) $commentAttributes->ObjectBound)
                         ->setAuthor((string) $commentAttributes->Author)
                         ->setText($this->parseRichText((string) $commentAttributes->Text));

src/PhpSpreadsheet/Reader/Gnumeric/PageSetup.php

@@ -24,6 +24,10 @@ class PageSetup
     {
         if (isset($sheet->PrintInformation)) {
             $printInformation = $sheet->PrintInformation[0];
+            if (!$printInformation) {
+                return $this;
+            }
+
             $scale = (string) $printInformation->Scale->attributes()['percentage'];
             $pageOrder = (string) $printInformation->order;
             $orientation = (string) $printInformation->orientation;

src/PhpSpreadsheet/Reader/Gnumeric/Properties.php

@@ -113,8 +113,10 @@ class Properties
 
                         break;
                     case 'user-defined':
-                        [, $attrName] = explode(':', $attributes['name']);
+                        if ($attributes) {
-                        $this->userDefinedProperties($attrName, $propertyValue);
+                            [, $attrName] = explode(':', (string) $attributes['name']);
+                            $this->userDefinedProperties($attrName, $propertyValue);
+                        }
 
                         break;
                 }

src/PhpSpreadsheet/Reader/Gnumeric/Styles.php

@@ -101,10 +101,6 @@ class Styles
     private function readStyles(SimpleXMLElement $styleRegion, int $maxRow, int $maxCol): void
     {
         foreach ($styleRegion as $style) {
-            if ($style === null) {
-                continue;
-            }
-
             $styleAttributes = $style->attributes();
             if ($styleAttributes !== null && ($styleAttributes['startRow'] <= $maxRow) && ($styleAttributes['startCol'] <= $maxCol)) {
                 $cellRange = $this->readStyleRange($styleAttributes, $maxCol, $maxRow);
@@ -114,8 +110,8 @@ class Styles
                 $styleArray = [];
                 // We still set the number format mask for date/time values, even if readDataOnly is true
                 //    so that we can identify whether a float is a float or a date value
-                $formatCode = (string) $styleAttributes['Format'];
+                $formatCode = $styleAttributes ? (string) $styleAttributes['Format'] : null;
-                if (Date::isDateTimeFormatCode($formatCode)) {
+                if ($formatCode && Date::isDateTimeFormatCode($formatCode)) {
                     $styleArray['numberFormat']['formatCode'] = $formatCode;
                 }
                 if ($this->readDataOnly === false && $styleAttributes !== null) {
@@ -183,7 +179,7 @@ class Styles
                 $styleArray['color']['rgb'] = self::parseGnumericColour($borderAttributes['Color']);
             }
 
-            self::addStyle($styleArray, 'borderStyle', $borderAttributes['Style']);
+            self::addStyle($styleArray, 'borderStyle', (string) $borderAttributes['Style']);
         }
 
         return $styleArray;
@@ -201,12 +197,12 @@ class Styles
 
     private function addColors(array &$styleArray, SimpleXMLElement $styleAttributes): void
     {
-        $RGB = self::parseGnumericColour($styleAttributes['Fore']);
+        $RGB = self::parseGnumericColour((string) $styleAttributes['Fore']);
         $styleArray['font']['color']['rgb'] = $RGB;
-        $RGB = self::parseGnumericColour($styleAttributes['Back']);
+        $RGB = self::parseGnumericColour((string) $styleAttributes['Back']);
         $shade = (string) $styleAttributes['Shade'];
         if (($RGB !== '000000') || ($shade !== '0')) {
-            $RGB2 = self::parseGnumericColour($styleAttributes['PatternColor']);
+            $RGB2 = self::parseGnumericColour((string) $styleAttributes['PatternColor']);
             if ($shade === '1') {
                 $styleArray['fill']['startColor']['rgb'] = $RGB;
                 $styleArray['fill']['endColor']['rgb'] = $RGB2;
@@ -234,8 +230,8 @@ class Styles
 
     private function readStyle(array $styleArray, SimpleXMLElement $styleAttributes, SimpleXMLElement $style): array
     {
-        self::addStyle2($styleArray, 'alignment', 'horizontal', $styleAttributes['HAlign']);
+        self::addStyle2($styleArray, 'alignment', 'horizontal', (string) $styleAttributes['HAlign']);
-        self::addStyle2($styleArray, 'alignment', 'vertical', $styleAttributes['VAlign']);
+        self::addStyle2($styleArray, 'alignment', 'vertical', (string) $styleAttributes['VAlign']);
         $styleArray['alignment']['wrapText'] = $styleAttributes['WrapText'] == '1';
         $styleArray['alignment']['textRotation'] = $this->calcRotation($styleAttributes);
         $styleArray['alignment']['shrinkToFit'] = $styleAttributes['ShrinkToFit'] == '1';
@@ -250,7 +246,7 @@ class Styles
             $styleArray['font']['bold'] = $fontAttributes['Bold'] == '1';
             $styleArray['font']['italic'] = $fontAttributes['Italic'] == '1';
             $styleArray['font']['strikethrough'] = $fontAttributes['StrikeThrough'] == '1';
-            self::addStyle2($styleArray, 'font', 'underline', $fontAttributes['Underline']);
+            self::addStyle2($styleArray, 'font', 'underline', (string) $fontAttributes['Underline']);
 
             switch ($fontAttributes['Script']) {
                 case '1':

src/PhpSpreadsheet/Reader/Ods.php

@@ -65,7 +65,7 @@ class Ods extends BaseReader
                         $manifest = $xml->children($namespacesContent['manifest']);
                         foreach ($manifest as $manifestDataSet) {
                             $manifestAttributes = $manifestDataSet->attributes($namespacesContent['manifest']);
-                            if ($manifestAttributes->{'full-path'} == '/') {
+                            if ($manifestAttributes && $manifestAttributes->{'full-path'} == '/') {
                                 $mimeType = (string) $manifestAttributes->{'media-type'};
 
                                 break;
@@ -357,7 +357,7 @@ class Ods extends BaseReader
                             break;
                         case 'table-row':
                             if ($childNode->hasAttributeNS($tableNs, 'number-rows-repeated')) {
-                                $rowRepeats = $childNode->getAttributeNS($tableNs, 'number-rows-repeated');
+                                $rowRepeats = (int) $childNode->getAttributeNS($tableNs, 'number-rows-repeated');
                             } else {
                                 $rowRepeats = 1;
                             }
@@ -514,7 +514,7 @@ class Ods extends BaseReader
 
                                             $dataValue = Date::PHPToExcel(
                                                 strtotime(
-                                                    '01-01-1970 ' . implode(':', sscanf($timeValue, 'PT%dH%dM%dS'))
+                                                    '01-01-1970 ' . implode(':', sscanf($timeValue, 'PT%dH%dM%dS') ?? [])
                                                 )
                                             );
                                             $formatting = NumberFormat::FORMAT_DATE_TIME4;
@@ -632,6 +632,7 @@ class Ods extends BaseReader
         if ($zip->locateName('settings.xml') !== false) {
             $this->processSettings($zip, $spreadsheet);
         }
+
         // Return
         return $spreadsheet;
     }

src/PhpSpreadsheet/Reader/Ods/Properties.php

@@ -26,7 +26,7 @@ class Properties
                 $this->setCoreProperties($docProps, $officePropertiesDC);
             }
 
-            $officePropertyMeta = (object) [];
+            $officePropertyMeta = [];
             if (isset($namespacesMeta['dc'])) {
                 $officePropertyMeta = $officePropertyData->children($namespacesMeta['meta']);
             }

src/PhpSpreadsheet/Reader/Xlsx.php

@@ -55,7 +55,7 @@ class Xlsx extends BaseReader
      *
      * @var Xlsx\Theme
      */
-    private static $theme = null;
+    private static $theme;
 
     /**
      * @var ZipArchive
@@ -182,7 +182,7 @@ class Xlsx extends BaseReader
             $relType = (string) $rel['Type'];
             $mainNS = self::REL_TO_MAIN[$relType] ?? Namespaces::MAIN;
             if ($mainNS !== '') {
-                $xmlWorkbook = $this->loadZip($rel['Target'], $mainNS);
+                $xmlWorkbook = $this->loadZip((string) $rel['Target'], $mainNS);
 
                 if ($xmlWorkbook->sheets) {
                     foreach ($xmlWorkbook->sheets->sheet as $eleSheet) {
@@ -246,7 +246,7 @@ class Xlsx extends BaseReader
                             'totalColumns' => 0,
                         ];
 
-                        $fileWorksheet = $worksheets[(string) self::getArrayItem(self::getAttributes($eleSheet, $namespace), 'id')];
+                        $fileWorksheet = (string) $worksheets[(string) self::getArrayItem(self::getAttributes($eleSheet, $namespace), 'id')];
                         $fileWorksheetPath = strpos($fileWorksheet, '/') === 0 ? substr($fileWorksheet, 1) : "$dir/$fileWorksheet";
 
                         $xml = new XMLReader();
@@ -408,13 +408,14 @@ class Xlsx extends BaseReader
         $wbRels = $this->loadZip("xl/_rels/${workbookBasename}.rels", Namespaces::RELATIONSHIPS);
         foreach ($wbRels->Relationship as $relx) {
             $rel = self::getAttributes($relx);
+            $relTarget = (string) $rel['Target'];
             switch ($rel['Type']) {
                 case "$xmlNamespaceBase/theme":
                     $themeOrderArray = ['lt1', 'dk1', 'lt2', 'dk2'];
                     $themeOrderAdditional = count($themeOrderArray);
                     $drawingNS = self::REL_TO_DRAWING[$xmlNamespaceBase] ?? Namespaces::DRAWINGML;
 
-                    $xmlTheme = $this->loadZip("xl/{$rel['Target']}", $drawingNS);
+                    $xmlTheme = $this->loadZip("xl/{$relTarget}", $drawingNS);
                     $xmlThemeName = self::getAttributes($xmlTheme);
                     $xmlTheme = $xmlTheme->children($drawingNS);
                     $themeName = (string) $xmlThemeName['name'];
@@ -431,10 +432,10 @@ class Xlsx extends BaseReader
                         }
                         if (isset($xmlColour->sysClr)) {
                             $xmlColourData = self::getAttributes($xmlColour->sysClr);
-                            $themeColours[$themePos] = $xmlColourData['lastClr'];
+                            $themeColours[$themePos] = (string) $xmlColourData['lastClr'];
                         } elseif (isset($xmlColour->srgbClr)) {
                             $xmlColourData = self::getAttributes($xmlColour->srgbClr);
-                            $themeColours[$themePos] = $xmlColourData['val'];
+                            $themeColours[$themePos] = (string) $xmlColourData['val'];
                         }
                     }
                     self::$theme = new Xlsx\Theme($themeName, $colourSchemeName, $themeColours);
@@ -448,34 +449,35 @@ class Xlsx extends BaseReader
         $propertyReader = new PropertyReader($this->securityScanner, $excel->getProperties());
         foreach ($rels->Relationship as $relx) {
             $rel = self::getAttributes($relx);
+            $relTarget = (string) $rel['Target'];
             $relType = (string) $rel['Type'];
             $mainNS = self::REL_TO_MAIN[$relType] ?? Namespaces::MAIN;
             switch ($relType) {
                 case Namespaces::CORE_PROPERTIES:
-                    $propertyReader->readCoreProperties($this->getFromZipArchive($zip, $rel['Target']));
+                    $propertyReader->readCoreProperties($this->getFromZipArchive($zip, $relTarget));
 
                     break;
                 case "$xmlNamespaceBase/extended-properties":
-                    $propertyReader->readExtendedProperties($this->getFromZipArchive($zip, $rel['Target']));
+                    $propertyReader->readExtendedProperties($this->getFromZipArchive($zip, $relTarget));
 
                     break;
                 case "$xmlNamespaceBase/custom-properties":
-                    $propertyReader->readCustomProperties($this->getFromZipArchive($zip, $rel['Target']));
+                    $propertyReader->readCustomProperties($this->getFromZipArchive($zip, $relTarget));
 
                     break;
                 //Ribbon
                 case Namespaces::EXTENSIBILITY:
-                    $customUI = $rel['Target'];
+                    $customUI = $relTarget;
-                    if ($customUI !== null) {
+                    if ($customUI) {
                         $this->readRibbon($excel, $customUI, $zip);
                     }
 
                     break;
                 case "$xmlNamespaceBase/officeDocument":
-                    $dir = dirname($rel['Target']);
+                    $dir = dirname($relTarget);
 
                     // Do not specify namespace in next stmt - do it in Xpath
-                    $relsWorkbook = $this->loadZip("$dir/_rels/" . basename($rel['Target']) . '.rels', '');
+                    $relsWorkbook = $this->loadZip("$dir/_rels/" . basename($relTarget) . '.rels', '');
                     $relsWorkbook->registerXPathNamespace('rel', Namespaces::RELATIONSHIPS);
 
                     $sharedStrings = [];
@@ -645,8 +647,8 @@ class Xlsx extends BaseReader
                     $dxfs = $styleReader->dxfs($this->readDataOnly);
                     $styles = $styleReader->styles();
 
-                    $xmlWorkbook = $this->loadZipNoNamespace($rel['Target'], $mainNS);
+                    $xmlWorkbook = $this->loadZipNoNamespace($relTarget, $mainNS);
-                    $xmlWorkbookNS = $this->loadZip($rel['Target'], $mainNS);
+                    $xmlWorkbookNS = $this->loadZip($relTarget, $mainNS);
 
                     // Set base date
                     if ($xmlWorkbookNS->workbookPr) {
@@ -694,7 +696,7 @@ class Xlsx extends BaseReader
                             //        and we're simply bringing the worksheet name in line with the formula, not the
                             //        reverse
                             $docSheet->setTitle((string) $eleSheetAttr['name'], false, false);
-                            $fileWorksheet = $worksheets[(string) self::getArrayItem(self::getAttributes($eleSheet, $xmlNamespaceBase), 'id')];
+                            $fileWorksheet = (string) $worksheets[(string) self::getArrayItem(self::getAttributes($eleSheet, $xmlNamespaceBase), 'id')];
                             $xmlSheet = $this->loadZipNoNamespace("$dir/$fileWorksheet", $mainNS);
                             $xmlSheetNS = $this->loadZip("$dir/$fileWorksheet", $mainNS);
 
@@ -881,7 +883,7 @@ class Xlsx extends BaseReader
 
                                 foreach ($xmlSheet->extLst->ext->children('x14', true)->dataValidations->dataValidation as $item) {
                                     $node = $xmlSheet->dataValidations->addChild('dataValidation');
-                                    foreach ($item->attributes() as $attr) {
+                                    foreach ($item->attributes() ?? [] as $attr) {
                                         $node->addAttribute($attr->getName(), $attr);
                                     }
                                     $node->addAttribute('sqref', $item->children('xm', true)->sqref);
@@ -1580,7 +1582,7 @@ class Xlsx extends BaseReader
                 switch ($contentType['ContentType']) {
                     case 'application/vnd.openxmlformats-officedocument.drawingml.chart+xml':
                         if ($this->includeCharts) {
-                            $chartEntryRef = ltrim($contentType['PartName'], '/');
+                            $chartEntryRef = ltrim((string) $contentType['PartName'], '/');
                             $chartElements = $this->loadZip($chartEntryRef);
                             $objChart = Chart::readChart($chartElements, basename($chartEntryRef, '.xml'));
 
@@ -1656,8 +1658,6 @@ class Xlsx extends BaseReader
     }
 
     /**
-     * @param SimpleXMLElement | null $is
-     *
      * @return RichText
      */
     private function parseRichText(?SimpleXMLElement $is)
@@ -1742,11 +1742,7 @@ class Xlsx extends BaseReader
         return $value;
     }
 
-    /**
+    private function readRibbon(Spreadsheet $excel, string $customUITarget, ZipArchive $zip): void
-     * @param mixed $customUITarget
-     * @param mixed $zip
-     */
-    private function readRibbon(Spreadsheet $excel, $customUITarget, $zip): void
     {
         $baseDir = dirname($customUITarget);
         $nameCustomUI = basename($customUITarget);
@@ -1990,11 +1986,12 @@ class Xlsx extends BaseReader
         $rels = $this->loadZip(self::INITIAL_FILE);
         foreach ($rels->children(Namespaces::RELATIONSHIPS)->Relationship as $rel) {
             $rel = self::getAttributes($rel);
-            switch ($rel['Type']) {
+            $type = (string) $rel['Type'];
+            switch ($type) {
                 case Namespaces::OFFICE_DOCUMENT:
                 case Namespaces::PURL_OFFICE_DOCUMENT:
-                    $basename = basename($rel['Target']);
+                    $basename = basename((string) $rel['Target']);
-                    $xmlNamespaceBase = dirname($rel['Type']);
+                    $xmlNamespaceBase = dirname($type);
                     if (preg_match('/workbook.*\.xml/', $basename)) {
                         $workbookBasename = $basename;
                     }

src/PhpSpreadsheet/Reader/Xlsx/AutoFilter.php

@@ -89,7 +89,7 @@ class AutoFilter
             $customFilters = $filterColumn->customFilters;
             //    Custom filters can an AND or an OR join;
             //        and there should only ever be one or two entries
-            if ((isset($customFilters['and'])) && ($customFilters['and'] == 1)) {
+            if ((isset($customFilters['and'])) && ((string) $customFilters['and'] === '1')) {
                 $column->setJoin(Column::AUTOFILTER_COLUMN_JOIN_AND);
             }
             foreach ($customFilters->customFilter as $filterRule) {
@@ -130,12 +130,12 @@ class AutoFilter
             //    We should only ever have one top10 filter
             foreach ($filterColumn->top10 as $filterRule) {
                 $column->createRule()->setRule(
-                    (((isset($filterRule['percent'])) && ($filterRule['percent'] == 1))
+                    (((isset($filterRule['percent'])) && ((string) $filterRule['percent'] === '1'))
                         ? Rule::AUTOFILTER_COLUMN_RULE_TOPTEN_PERCENT
                         : Rule::AUTOFILTER_COLUMN_RULE_TOPTEN_BY_VALUE
                     ),
                     (string) $filterRule['val'],
-                    (((isset($filterRule['top'])) && ($filterRule['top'] == 1))
+                    (((isset($filterRule['top'])) && ((string) $filterRule['top'] === '1'))
                         ? Rule::AUTOFILTER_COLUMN_RULE_TOPTEN_TOP
                         : Rule::AUTOFILTER_COLUMN_RULE_TOPTEN_BOTTOM
                     )

src/PhpSpreadsheet/Reader/Xlsx/Chart.php

@@ -31,7 +31,9 @@ class Chart
             } elseif ($format == 'integer') {
                 return (int) $attributes[$name];
             } elseif ($format == 'boolean') {
-                return (bool) ($attributes[$name] === '0' || $attributes[$name] !== 'true') ? false : true;
+                $value = (string) $attributes[$name];
+
+                return $value === 'true' || $value === '1';
             }
 
             return (float) $attributes[$name];
@@ -482,7 +484,7 @@ class Chart
                 }
 
                 $fontSize = (self::getAttribute($titleDetailElement->rPr, 'sz', 'integer'));
-                if ($fontSize !== null) {
+                if (is_int($fontSize)) {
                     $objText->getFont()->setSize(floor($fontSize / 100));
                 }
 

src/PhpSpreadsheet/Reader/Xlsx/Styles.php

@@ -21,7 +21,7 @@ class Styles extends BaseParserClass
      *
      * @var Theme
      */
-    private static $theme = null;
+    private static $theme;
 
     private $styles = [];
 

src/PhpSpreadsheet/Reader/Xml.php

@@ -361,7 +361,7 @@ class Xml extends BaseReader
                             $columnTo = $columnID;
                             if (isset($cell_ss['MergeAcross'])) {
                                 $additionalMergedCells += (int) $cell_ss['MergeAcross'];
-                                $columnTo = Coordinate::stringFromColumnIndex(Coordinate::columnIndexFromString($columnID) + $cell_ss['MergeAcross']);
+                                $columnTo = Coordinate::stringFromColumnIndex((int) (Coordinate::columnIndexFromString($columnID) + $cell_ss['MergeAcross']));
                             }
                             $rowTo = $rowID;
                             if (isset($cell_ss['MergeDown'])) {

src/PhpSpreadsheet/Reader/Xml/PageSettings.php

@@ -62,6 +62,10 @@ class PageSettings
             foreach ($xmlX->WorksheetOptions->PageSetup as $pageSetupData) {
                 foreach ($pageSetupData as $pageSetupKey => $pageSetupValue) {
                     $pageSetupAttributes = $pageSetupValue->attributes($namespaces['x']);
+                    if (!$pageSetupAttributes) {
+                        continue;
+                    }
+
                     switch ($pageSetupKey) {
                         case 'Layout':
                             $this->setLayout($printDefaults, $pageSetupAttributes);

src/PhpSpreadsheet/Reader/Xml/Style.php

@@ -35,9 +35,12 @@ class Style
             foreach ($style as $styleType => $styleDatax) {
                 $styleData = $styleDatax ?? new SimpleXMLElement('<xml></xml>');
                 $styleAttributes = $styleData->attributes($namespaces['ss']);
+
                 switch ($styleType) {
                     case 'Alignment':
-                        $alignment = $alignmentStyleParser->parseStyle($styleAttributes);
+                        if ($styleAttributes) {
+                            $alignment = $alignmentStyleParser->parseStyle($styleAttributes);
+                        }
 
                         break;
                     case 'Borders':
@@ -45,15 +48,21 @@ class Style
 
                         break;
                     case 'Font':
-                        $font = $fontStyleParser->parseStyle($styleAttributes);
+                        if ($styleAttributes) {
+                            $font = $fontStyleParser->parseStyle($styleAttributes);
+                        }
 
                         break;
                     case 'Interior':
-                        $fill = $fillStyleParser->parseStyle($styleAttributes);
+                        if ($styleAttributes) {
+                            $fill = $fillStyleParser->parseStyle($styleAttributes);
+                        }
 
                         break;
                     case 'NumberFormat':
-                        $numberFormat = $numberFormatStyleParser->parseStyle($styleAttributes);
+                        if ($styleAttributes) {
+                            $numberFormat = $numberFormatStyleParser->parseStyle($styleAttributes);
+                        }
 
                         break;
                 }

src/PhpSpreadsheet/Settings.php

@@ -24,7 +24,7 @@ class Settings
      *
      * @var int
      */
-    private static $libXmlLoaderOptions = null;
+    private static $libXmlLoaderOptions;
 
     /**
      * Allow/disallow libxml_disable_entity_loader() call when not thread safe.

src/PhpSpreadsheet/Shared/Font.php

@@ -112,7 +112,7 @@ class Font
      *
      * @var string
      */
-    private static $trueTypeFontPath = null;
+    private static $trueTypeFontPath;
 
     /**
      * How wide is a default column for a given default font and size?

src/PhpSpreadsheet/Style/Conditional.php

@@ -263,7 +263,7 @@ class Conditional implements IComparable
     /**
      * get DataBar.
      *
-     * @return ConditionalDataBar | null
+     * @return null|ConditionalDataBar
      */
     public function getDataBar()
     {

src/PhpSpreadsheet/Style/ConditionalFormatting/ConditionalFormattingRuleExtension.php

@@ -70,11 +70,12 @@ class ConditionalFormattingRuleExtension
 
                 foreach ($extFormattingsXml->children($ns['x14']) as $extFormattingXml) {
                     $extCfRuleXml = $extFormattingXml->cfRule;
-                    if (((string) $extCfRuleXml->attributes()->type) !== Conditional::CONDITION_DATABAR) {
+                    $attributes = $extCfRuleXml->attributes();
+                    if (!$attributes || ((string) $attributes->type) !== Conditional::CONDITION_DATABAR) {
                         continue;
                     }
 
-                    $extFormattingRuleObj = new self((string) $extCfRuleXml->attributes()->id);
+                    $extFormattingRuleObj = new self((string) $attributes->id);
                     $extFormattingRuleObj->setSqref((string) $extFormattingXml->children($ns['xm'])->sqref);
                     $conditionalFormattingRuleExtensions[$extFormattingRuleObj->getId()] = $extFormattingRuleObj;
 
@@ -136,11 +137,16 @@ class ConditionalFormattingRuleExtension
         $cfvoIndex = 0;
         foreach ($dataBarXml->cfvo as $cfvo) {
             $f = (string) $cfvo->children($ns['xm'])->f;
+            $attributes = $cfvo->attributes();
+            if (!($attributes)) {
+                continue;
+            }
+
             if ($cfvoIndex === 0) {
-                $extDataBarObj->setMinimumConditionalFormatValueObject(new ConditionalFormatValueObject((string) $cfvo->attributes()['type'], null, (empty($f) ? null : $f)));
+                $extDataBarObj->setMinimumConditionalFormatValueObject(new ConditionalFormatValueObject((string) $attributes['type'], null, (empty($f) ? null : $f)));
             }
             if ($cfvoIndex === 1) {
-                $extDataBarObj->setMaximumConditionalFormatValueObject(new ConditionalFormatValueObject((string) $cfvo->attributes()['type'], null, (empty($f) ? null : $f)));
+                $extDataBarObj->setMaximumConditionalFormatValueObject(new ConditionalFormatValueObject((string) $attributes['type'], null, (empty($f) ? null : $f)));
             }
             ++$cfvoIndex;
         }

tests/PhpSpreadsheetTests/Writer/Xlsx/UnparsedDataTest.php

@@ -65,13 +65,16 @@ class UnparsedDataTest extends TestCase
 
         // xl/workbook.xml
         $xmlWorkbook = simplexml_load_string($resultWorkbookRaw, 'SimpleXMLElement', Settings::getLibXmlLoaderOptions());
+        self::assertNotFalse($xmlWorkbook);
         if (!$xmlWorkbook->workbookProtection) {
             self::fail('workbook.xml/workbookProtection not found!');
         } else {
             self::assertEquals($xmlWorkbook->workbookProtection['workbookPassword'], 'CBEB', 'workbook.xml/workbookProtection[workbookPassword] is wrong!');
             self::assertEquals($xmlWorkbook->workbookProtection['lockStructure'], 'true', 'workbook.xml/workbookProtection[lockStructure] is wrong!');
 
+            self::assertNotNull($xmlWorkbook->sheets->sheet[0]);
             self::assertEquals($xmlWorkbook->sheets->sheet[0]['state'], '', 'workbook.xml/sheets/sheet[0][state] is wrong!');
+            self::assertNotNull($xmlWorkbook->sheets->sheet[1]);
             self::assertEquals($xmlWorkbook->sheets->sheet[1]['state'], 'hidden', 'workbook.xml/sheets/sheet[1][state] is wrong!');
         }
         unset($xmlWorkbook);