Reduce PHPStan error in tests

composer.json

@@ -81,6 +81,7 @@
         "mpdf/mpdf": "^8.0",
         "phpcompatibility/php-compatibility": "^9.3",
         "phpstan/phpstan": "^0.12.82",
+        "phpstan/phpstan-phpunit": "^0.12.18",
         "phpunit/phpunit": "^8.5",
         "squizlabs/php_codesniffer": "^3.5",
         "tecnickcom/tcpdf": "^6.3"

composer.lock

@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "89b62d75519340c289a3a763245f1ca0",
+    "content-hash": "3be2673a6367d296c616bf9c34b77953",
     "packages": [
         {
             "name": "ezyang/htmlpurifier",
@@ -2023,6 +2023,61 @@
             ],
             "time": "2021-03-19T06:08:17+00:00"
         },
+        {
+            "name": "phpstan/phpstan-phpunit",
+            "version": "0.12.18",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/phpstan/phpstan-phpunit.git",
+                "reference": "ab44aec7cfb5cb267b8bc30a8caea86dd50d1f72"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/phpstan/phpstan-phpunit/zipball/ab44aec7cfb5cb267b8bc30a8caea86dd50d1f72",
+                "reference": "ab44aec7cfb5cb267b8bc30a8caea86dd50d1f72",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1 || ^8.0",
+                "phpstan/phpstan": "^0.12.60"
+            },
+            "conflict": {
+                "phpunit/phpunit": "<7.0"
+            },
+            "require-dev": {
+                "phing/phing": "^2.16.3",
+                "php-parallel-lint/php-parallel-lint": "^1.2",
+                "phpstan/phpstan-strict-rules": "^0.12.6",
+                "phpunit/phpunit": "^7.5.20"
+            },
+            "type": "phpstan-extension",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.12-dev"
+                },
+                "phpstan": {
+                    "includes": [
+                        "extension.neon",
+                        "rules.neon"
+                    ]
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "PHPStan\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PHPUnit extensions and rules for PHPStan",
+            "support": {
+                "issues": "https://github.com/phpstan/phpstan-phpunit/issues",
+                "source": "https://github.com/phpstan/phpstan-phpunit/tree/0.12.18"
+            },
+            "time": "2021-03-06T11:51:27+00:00"
+        },
         {
             "name": "phpunit/php-code-coverage",
             "version": "7.0.14",

phpstan.neon.dist

@@ -1,5 +1,7 @@
 includes:
-	- phpstan-baseline.neon
+    - phpstan-baseline.neon
+    - vendor/phpstan/phpstan-phpunit/extension.neon
+    - vendor/phpstan/phpstan-phpunit/rules.neon
 
 parameters:
     level: max
@@ -8,11 +10,15 @@ parameters:
         - tests/
     parallel:
         processTimeout: 300.0
+    checkMissingIterableValueType: false
     ignoreErrors:
         - '~^Class GdImage not found\.$~'
         - '~^Return typehint of method .* has invalid type GdImage\.$~'
         - '~^Property .* has unknown class GdImage as its type\.$~'
         - '~^Parameter .* of method .* has invalid typehint type GdImage\.$~'
+        # Accept a bit anything for assert methods
+        - '~^Parameter \#2 .* of static method PHPUnit\\Framework\\Assert\:\:assert\w+\(\) expects .*, .* given\.$~'
+        - '~^Method PhpOffice\\PhpSpreadsheetTests\\.*\:\:test.*\(\) has parameter \$args with no typehint specified\.$~'
 
         # Ignore all JpGraph issues
         - '~^Constant (MARK_CIRCLE|MARK_CROSS|MARK_DIAMOND|MARK_DTRIANGLE|MARK_FILLEDCIRCLE|MARK_SQUARE|MARK_STAR|MARK_UTRIANGLE|MARK_X|SIDE_RIGHT) not found\.$~'

samples/Reader/20_Reader_worksheet_hyperlink_image.php

@@ -1,5 +1,6 @@
 <?php
 
+use PhpOffice\PhpSpreadsheet\Shared\File;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
 
 require __DIR__ . '/../Header.php';
@@ -35,7 +36,7 @@ $helper->log('Write link: ' . $baseUrl);
 
 $drawing->setWorksheet($aSheet);
 
-$filename = tempnam(\PhpOffice\PhpSpreadsheet\Shared\File::sysGetTempDir(), 'phpspreadsheet-test');
+$filename = File::temporaryFilename();
 
 $writer = \PhpOffice\PhpSpreadsheet\IOFactory::createWriter($spreadsheet, $inputFileType);
 $writer->save($filename);

src/PhpSpreadsheet/Calculation/DateTimeExcel/WeekDay.php

@@ -17,7 +17,7 @@ class WeekDay
      * Excel Function:
      *        WEEKDAY(dateValue[,style])
      *
-     * @param float|int|string $dateValue Excel date serial value (float), PHP date timestamp (integer),
+     * @param null|float|int|string $dateValue Excel date serial value (float), PHP date timestamp (integer),
      *                                    PHP DateTime object, or a standard date string
      * @param int $style A number that determines the type of return value
      *                                        1 or omitted    Numbers 1 (Sunday) through 7 (Saturday).

src/PhpSpreadsheet/Chart/Legend.php

@@ -131,18 +131,10 @@ class Legend
      * Set allow overlay of other elements?
      *
      * @param bool $overlay
-     *
-     * @return bool
      */
-    public function setOverlay($overlay)
+    public function setOverlay($overlay): void
     {
-        if (!is_bool($overlay)) {
-            return false;
-        }
-
         $this->overlay = $overlay;
-
-        return true;
     }
 
     /**

src/PhpSpreadsheet/Collection/Cells.php

@@ -12,7 +12,7 @@ use Psr\SimpleCache\CacheInterface;
 class Cells
 {
     /**
-     * @var \Psr\SimpleCache\CacheInterface
+     * @var CacheInterface
      */
     private $cache;
 
@@ -405,7 +405,7 @@ class Cells
      * @param string $pCoord Coordinate of the cell to update
      * @param Cell $cell Cell to update
      *
-     * @return \PhpOffice\PhpSpreadsheet\Cell\Cell
+     * @return Cell
      */
     public function add($pCoord, Cell $cell)
     {
@@ -426,7 +426,7 @@ class Cells
      *
      * @param string $pCoord Coordinate of the cell
      *
-     * @return null|\PhpOffice\PhpSpreadsheet\Cell\Cell Cell that was found, or null if not found
+     * @return null|Cell Cell that was found, or null if not found
      */
     public function get($pCoord)
     {

src/PhpSpreadsheet/Shared/File.php

@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheet\Shared;
 
 use InvalidArgumentException;
+use PhpOffice\PhpSpreadsheet\Exception;
 use ZipArchive;
 
 class File
@@ -124,6 +125,16 @@ class File
         return realpath(sys_get_temp_dir());
     }
 
+    public static function temporaryFilename(): string
+    {
+        $filename = tempnam(self::sysGetTempDir(), 'phpspreadsheet');
+        if ($filename === false) {
+            throw new Exception('Could not create temporary file');
+        }
+
+        return $filename;
+    }
+
     /**
      * Assert that given path is an existing file and is readable, otherwise throw exception.
      *

tests/PhpSpreadsheetTests/Calculation/CalculationTest.php

@@ -10,8 +10,14 @@ use PHPUnit\Framework\TestCase;
 
 class CalculationTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
+    /**
+     * @var string
+     */
     private $locale;
 
     protected function setUp(): void
@@ -47,7 +53,7 @@ class CalculationTest extends TestCase
         self::assertEquals($expectedResultOpenOffice, $resultOpenOffice, 'should be OpenOffice compatible');
     }
 
-    public function providerBinaryComparisonOperation()
+    public function providerBinaryComparisonOperation(): array
     {
         return require 'tests/data/CalculationBinaryComparisonOperation.php';
     }
@@ -64,7 +70,7 @@ class CalculationTest extends TestCase
         self::assertIsCallable($functionCall);
     }
 
-    public function providerGetFunctions()
+    public function providerGetFunctions(): array
     {
         return Calculation::getInstance()->getFunctions();
     }
@@ -89,7 +95,7 @@ class CalculationTest extends TestCase
         self::assertTrue($calculation->setLocale($locale));
     }
 
-    public function providerCanLoadAllSupportedLocales()
+    public function providerCanLoadAllSupportedLocales(): array
     {
         return [
             ['bg'],
@@ -118,11 +124,13 @@ class CalculationTest extends TestCase
         $calculation = Calculation::getInstance();
 
         $tree = $calculation->parseFormula('=_xlfn.ISFORMULA(A1)');
+        self::assertIsArray($tree);
         self::assertCount(3, $tree);
         $function = $tree[2];
         self::assertEquals('Function', $function['type']);
 
         $tree = $calculation->parseFormula('=_xlfn.STDEV.S(A1:B2)');
+        self::assertIsArray($tree);
         self::assertCount(5, $tree);
         $function = $tree[4];
         self::assertEquals('Function', $function['type']);
@@ -205,6 +213,7 @@ class CalculationTest extends TestCase
         // Very simple formula
         $formula = '=IF(A1="please +",B1)';
         $tokens = $calculation->parseFormula($formula);
+        self::assertIsArray($tokens);
 
         $foundEqualAssociatedToStoreKey = false;
         $foundConditionalOnB1 = false;
@@ -234,6 +243,7 @@ class CalculationTest extends TestCase
         // Internal operation
         $formula = '=IF(A1="please +",SUM(B1:B3))+IF(A2="please *",PRODUCT(C1:C3), C1)';
         $tokens = $calculation->parseFormula($formula);
+        self::assertIsArray($tokens);
 
         $plusGotTagged = false;
         $productFunctionCorrectlyTagged = false;
@@ -263,6 +273,7 @@ class CalculationTest extends TestCase
 
         $formula = '=IF(A1="please +",SUM(B1:B3),1+IF(NOT(A2="please *"),C2-C1,PRODUCT(C1:C3)))';
         $tokens = $calculation->parseFormula($formula);
+        self::assertIsArray($tokens);
 
         $plusCorrectlyTagged = false;
         $productFunctionCorrectlyTagged = false;
@@ -307,6 +318,8 @@ class CalculationTest extends TestCase
 
         $formula = '=IF(A1="flag",IF(A2<10, 0) + IF(A3<10000, 0))';
         $tokens = $calculation->parseFormula($formula);
+        self::assertIsArray($tokens);
+
         $properlyTaggedPlus = false;
         foreach ($tokens as $token) {
             $isPlus = $token['value'] === '+';
@@ -367,7 +380,7 @@ class CalculationTest extends TestCase
         self::assertEquals($expectedResult, $calculated);
     }
 
-    public function dataProviderBranchPruningFullExecution()
+    public function dataProviderBranchPruningFullExecution(): array
     {
         return require 'tests/data/Calculation/Calculation.php';
     }

tests/PhpSpreadsheetTests/Calculation/DefinedNameConfusedForCellTest.php

@@ -2,20 +2,23 @@
 
 namespace PhpOffice\PhpSpreadsheetTests\Calculation;
 
+use PhpOffice\PhpSpreadsheet\IOFactory;
+use PhpOffice\PhpSpreadsheet\NamedRange;
 use PhpOffice\PhpSpreadsheet\Shared\File;
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
 use PHPUnit\Framework\TestCase;
 
 class DefinedNameConfusedForCellTest extends TestCase
 {
     public function testDefinedName(): void
     {
-        $obj = new \PhpOffice\PhpSpreadsheet\Spreadsheet();
+        $obj = new Spreadsheet();
         $sheet0 = $obj->setActiveSheetIndex(0);
         $sheet0->setCellValue('A1', 2);
-        $obj->addNamedRange(new \PhpOffice\PhpSpreadsheet\NamedRange('A1A', $sheet0, 'A1'));
+        $obj->addNamedRange(new NamedRange('A1A', $sheet0, 'A1'));
         $sheet0->setCellValue('B1', '=2*A1A');
-        $writer = \PhpOffice\PhpSpreadsheet\IOFactory::createWriter($obj, 'Xlsx');
+        $writer = IOFactory::createWriter($obj, 'Xlsx');
-        $filename = tempnam(File::sysGetTempDir(), 'phpspreadsheet-test');
+        $filename = File::temporaryFilename();
         $writer->save($filename);
         self::assertTrue(true);
         unlink($filename);

tests/PhpSpreadsheetTests/Calculation/Engine/RangeTest.php

@@ -9,7 +9,10 @@ use PHPUnit\Framework\TestCase;
 
 class RangeTest extends TestCase
 {
-    protected $spreadSheet;
+    /**
+     * @var Spreadsheet
+     */
+    private $spreadSheet;
 
     protected function setUp(): void
     {
@@ -40,7 +43,7 @@ class RangeTest extends TestCase
         self::assertSame($expectedResult, $actualRresult);
     }
 
-    public function providerRangeEvaluation()
+    public function providerRangeEvaluation(): array
     {
         return[
             ['=SUM(A1:B3,A1:C2)', 48],
@@ -88,7 +91,7 @@ class RangeTest extends TestCase
         self::assertSame($expectedResult, $sumRresult);
     }
 
-    public function providerNamedRangeEvaluation()
+    public function providerNamedRangeEvaluation(): array
     {
         return[
             ['$A$1:$B$3', '$A$1:$C$2', '=SUM(GROUP1,GROUP2)', 48],
@@ -123,7 +126,7 @@ class RangeTest extends TestCase
         self::assertSame($expectedResult, $sumRresult);
     }
 
-    public function providerUTF8NamedRangeEvaluation()
+    public function providerUTF8NamedRangeEvaluation(): array
     {
         return[
             [['Γειά', 'σου', 'Κόσμε'], ['$A$1', '$B$1:$B$2', '$C$1:$C$3'], '=SUM(Γειά,σου,Κόσμε)', 26],
@@ -151,7 +154,7 @@ class RangeTest extends TestCase
         self::assertSame($expectedCount, $actualCount);
     }
 
-    public function providerCompositeNamedRangeEvaluation()
+    public function providerCompositeNamedRangeEvaluation(): array
     {
         return[
             //  Calculation engine doesn't yet handle union ranges with overlap

tests/PhpSpreadsheetTests/Calculation/FormulaAsStringTest.php

@@ -39,7 +39,7 @@ class FormulaAsStringTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerFunctionsAsString()
+    public function providerFunctionsAsString(): array
     {
         return require 'tests/data/Calculation/FunctionsAsString.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DAverageTest.php

@@ -27,7 +27,7 @@ class DAverageTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DAverageTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Quarter', 'Area', 'Sales Rep.', 'Sales'],
@@ -63,7 +63,7 @@ class DAverageTest extends TestCase
         ];
     }
 
-    public function providerDAverage()
+    public function providerDAverage(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DCountATest.php

@@ -27,7 +27,7 @@ class DCountATest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DCountATest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DCountATest extends TestCase
         ];
     }
 
-    public function providerDCountA()
+    public function providerDCountA(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DCountTest.php

@@ -27,7 +27,7 @@ class DCountTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DCountTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DCountTest extends TestCase
         ];
     }
 
-    protected function database3()
+    private function database3(): array
     {
         return [
             ['Status', 'Value'],
@@ -74,7 +74,7 @@ class DCountTest extends TestCase
         ];
     }
 
-    public function providerDCount()
+    public function providerDCount(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DGetTest.php

@@ -27,7 +27,7 @@ class DGetTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DGetTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Quarter', 'Area', 'Sales Rep.', 'Sales'],
@@ -63,7 +63,7 @@ class DGetTest extends TestCase
         ];
     }
 
-    public function providerDGet()
+    public function providerDGet(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DMaxTest.php

@@ -27,7 +27,7 @@ class DMaxTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DMaxTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Quarter', 'Area', 'Sales Rep.', 'Sales'],
@@ -63,7 +63,7 @@ class DMaxTest extends TestCase
         ];
     }
 
-    public function providerDMax()
+    public function providerDMax(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DMinTest.php

@@ -27,7 +27,7 @@ class DMinTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DMinTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DMinTest extends TestCase
         ];
     }
 
-    public function providerDMin()
+    public function providerDMin(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DProductTest.php

@@ -28,7 +28,7 @@ class DProductTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -41,7 +41,7 @@ class DProductTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Date', 'Test', 'Score'],
@@ -60,7 +60,7 @@ class DProductTest extends TestCase
         ];
     }
 
-    public function providerDProduct()
+    public function providerDProduct(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DStDevPTest.php

@@ -27,7 +27,7 @@ class DStDevPTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DStDevPTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DStDevPTest extends TestCase
         ];
     }
 
-    public function providerDStDevP()
+    public function providerDStDevP(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DStDevTest.php

@@ -27,7 +27,7 @@ class DStDevTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DStDevTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DStDevTest extends TestCase
         ];
     }
 
-    public function providerDStDev()
+    public function providerDStDev(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DSumTest.php

@@ -27,7 +27,7 @@ class DSumTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DSumTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Quarter', 'Area', 'Sales Rep.', 'Sales'],
@@ -63,7 +63,7 @@ class DSumTest extends TestCase
         ];
     }
 
-    public function providerDSum()
+    public function providerDSum(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DVarPTest.php

@@ -27,7 +27,7 @@ class DVarPTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DVarPTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DVarPTest extends TestCase
         ];
     }
 
-    public function providerDVarP()
+    public function providerDVarP(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/Database/DVarTest.php

@@ -27,7 +27,7 @@ class DVarTest extends TestCase
         self::assertSame($expectedResult, $result);
     }
 
-    protected function database1()
+    private function database1(): array
     {
         return [
             ['Tree', 'Height', 'Age', 'Yield', 'Profit'],
@@ -40,7 +40,7 @@ class DVarTest extends TestCase
         ];
     }
 
-    protected function database2()
+    private function database2(): array
     {
         return [
             ['Name', 'Gender', 'Age', 'Subject', 'Score'],
@@ -59,7 +59,7 @@ class DVarTest extends TestCase
         ];
     }
 
-    public function providerDVar()
+    public function providerDVar(): array
     {
         return [
             [

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/AllSetupTeardown.php

@@ -6,18 +6,34 @@ use PhpOffice\PhpSpreadsheet\Calculation\Exception as CalcException;
 use PhpOffice\PhpSpreadsheet\Calculation\Functions;
 use PhpOffice\PhpSpreadsheet\Shared\Date;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
+use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 use PHPUnit\Framework\TestCase;
 
 class AllSetupTeardown extends TestCase
 {
-    protected $compatibilityMode;
+    /**
+     * @var string
+     */
+    private $compatibilityMode;
 
-    protected $excelCalendar;
+    /**
+     * @var int
+     */
+    private $excelCalendar;
 
-    protected $returnDateType;
+    /**
+     * @var string
+     */
+    private $returnDateType;
 
+    /**
+     * @var Spreadsheet
+     */
     protected $spreadsheet;
 
+    /**
+     * @var Worksheet
+     */
     protected $sheet;
 
     protected function setUp(): void
@@ -35,8 +51,6 @@ class AllSetupTeardown extends TestCase
         Functions::setCompatibilityMode($this->compatibilityMode);
         Functions::setReturnDateType($this->returnDateType);
         $this->spreadsheet->disconnectWorksheets();
-        $this->spreadsheet = null;
-        $this->sheet = null;
     }
 
     protected static function setMac1904(): void

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/DateDifTest.php

@@ -18,7 +18,7 @@ class DateDifTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerDATEDIF()
+    public function providerDATEDIF(): array
     {
         return require 'tests/data/Calculation/DateTime/DATEDIF.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/DateTest.php

@@ -20,7 +20,7 @@ class DateTest extends AllSetupTeardown
         self::assertEquals($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerDATE()
+    public function providerDATE(): array
     {
         return require 'tests/data/Calculation/DateTime/DATE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/DateValueTest.php

@@ -37,7 +37,7 @@ class DateValueTest extends AllSetupTeardown
         self::assertEqualsWithDelta($expectedResult, $result, 1E-8);
     }
 
-    public function providerDATEVALUE()
+    public function providerDATEVALUE(): array
     {
         return require 'tests/data/Calculation/DateTime/DATEVALUE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/DayTest.php

@@ -18,7 +18,7 @@ class DayTest extends AllSetupTeardown
         self::assertSame($expectedResultExcel, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerDAY()
+    public function providerDAY(): array
     {
         return require 'tests/data/Calculation/DateTime/DAY.php';
     }
@@ -37,7 +37,7 @@ class DayTest extends AllSetupTeardown
         self::assertSame($expectedResultOpenOffice, $sheet->getCell('A2')->getCalculatedValue());
     }
 
-    public function providerDAYOpenOffice()
+    public function providerDAYOpenOffice(): array
     {
         return require 'tests/data/Calculation/DateTime/DAYOpenOffice.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/Days360Test.php

@@ -19,7 +19,7 @@ class Days360Test extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerDAYS360()
+    public function providerDAYS360(): array
     {
         return require 'tests/data/Calculation/DateTime/DAYS360.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/DaysTest.php

@@ -24,7 +24,7 @@ class DaysTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerDAYS()
+    public function providerDAYS(): array
     {
         return require 'tests/data/Calculation/DateTime/DAYS.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/EDateTest.php

@@ -20,7 +20,7 @@ class EDateTest extends AllSetupTeardown
         self::assertEquals($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerEDATE()
+    public function providerEDATE(): array
     {
         return require 'tests/data/Calculation/DateTime/EDATE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/EoMonthTest.php

@@ -20,7 +20,7 @@ class EoMonthTest extends AllSetupTeardown
         self::assertEquals($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerEOMONTH()
+    public function providerEOMONTH(): array
     {
         return require 'tests/data/Calculation/DateTime/EOMONTH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/HourTest.php

@@ -18,7 +18,7 @@ class HourTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerHOUR()
+    public function providerHOUR(): array
     {
         return require 'tests/data/Calculation/DateTime/HOUR.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/IsoWeekNumTest.php

@@ -19,7 +19,7 @@ class IsoWeekNumTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerISOWEEKNUM()
+    public function providerISOWEEKNUM(): array
     {
         return require 'tests/data/Calculation/DateTime/ISOWEEKNUM.php';
     }
@@ -40,7 +40,7 @@ class IsoWeekNumTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerISOWEEKNUM1904()
+    public function providerISOWEEKNUM1904(): array
     {
         return require 'tests/data/Calculation/DateTime/ISOWEEKNUM1904.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/MinuteTest.php

@@ -18,7 +18,7 @@ class MinuteTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerMINUTE()
+    public function providerMINUTE(): array
     {
         return require 'tests/data/Calculation/DateTime/MINUTE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/MonthTest.php

@@ -18,7 +18,7 @@ class MonthTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerMONTH()
+    public function providerMONTH(): array
     {
         return require 'tests/data/Calculation/DateTime/MONTH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/NetworkDaysTest.php

@@ -45,7 +45,7 @@ class NetworkDaysTest extends AllSetupTeardown
         self::assertEquals($expectedResult, $sheet->getCell('B1')->getCalculatedValue());
     }
 
-    public function providerNETWORKDAYS()
+    public function providerNETWORKDAYS(): array
     {
         return require 'tests/data/Calculation/DateTime/NETWORKDAYS.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/SecondTest.php

@@ -18,7 +18,7 @@ class SecondTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerSECOND()
+    public function providerSECOND(): array
     {
         return require 'tests/data/Calculation/DateTime/SECOND.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/TimeTest.php

@@ -22,7 +22,7 @@ class TimeTest extends AllSetupTeardown
         self::assertEqualsWithDelta($expectedResult, $sheet->getCell('A1')->getCalculatedValue(), 1E-8);
     }
 
-    public function providerTIME()
+    public function providerTIME(): array
     {
         return require 'tests/data/Calculation/DateTime/TIME.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/TimeValueTest.php

@@ -22,7 +22,7 @@ class TimeValueTest extends AllSetupTeardown
         self::assertEqualsWithDelta($expectedResult, $result, 1E-8);
     }
 
-    public function providerTIMEVALUE()
+    public function providerTIMEVALUE(): array
     {
         return require 'tests/data/Calculation/DateTime/TIMEVALUE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/WeekDayTest.php

@@ -20,7 +20,7 @@ class WeekDayTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerWEEKDAY()
+    public function providerWEEKDAY(): array
     {
         return require 'tests/data/Calculation/DateTime/WEEKDAY.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/WeekNumTest.php

@@ -18,7 +18,7 @@ class WeekNumTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerWEEKNUM()
+    public function providerWEEKNUM(): array
     {
         return require 'tests/data/Calculation/DateTime/WEEKNUM.php';
     }
@@ -38,7 +38,7 @@ class WeekNumTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerWEEKNUM1904()
+    public function providerWEEKNUM1904(): array
     {
         return require 'tests/data/Calculation/DateTime/WEEKNUM1904.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/WorkDayTest.php

@@ -45,7 +45,7 @@ class WorkDayTest extends AllSetupTeardown
         self::assertEquals($expectedResult, $sheet->getCell('B1')->getCalculatedValue());
     }
 
-    public function providerWORKDAY()
+    public function providerWORKDAY(): array
     {
         return require 'tests/data/Calculation/DateTime/WORKDAY.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/YearFracTest.php

@@ -37,7 +37,7 @@ class YearFracTest extends AllSetupTeardown
         self::assertEqualswithDelta($expectedResult, $sheet->getCell('B1')->getCalculatedValue(), 1E-6);
     }
 
-    public function providerYEARFRAC()
+    public function providerYEARFRAC(): array
     {
         return require 'tests/data/Calculation/DateTime/YEARFRAC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/DateTime/YearTest.php

@@ -18,7 +18,7 @@ class YearTest extends AllSetupTeardown
         self::assertSame($expectedResult, $sheet->getCell('A1')->getCalculatedValue());
     }
 
-    public function providerYEAR()
+    public function providerYEAR(): array
     {
         return require 'tests/data/Calculation/DateTime/YEAR.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BesselITest.php

@@ -26,7 +26,7 @@ class BesselITest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::BESSEL_PRECISION);
     }
 
-    public function providerBESSELI()
+    public function providerBESSELI(): array
     {
         return require 'tests/data/Calculation/Engineering/BESSELI.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BesselJTest.php

@@ -26,7 +26,7 @@ class BesselJTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::BESSEL_PRECISION);
     }
 
-    public function providerBESSEJ()
+    public function providerBESSEJ(): array
     {
         return require 'tests/data/Calculation/Engineering/BESSELJ.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BesselKTest.php

@@ -26,7 +26,7 @@ class BesselKTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::BESSEL_PRECISION);
     }
 
-    public function providerBESSELK()
+    public function providerBESSELK(): array
     {
         return require 'tests/data/Calculation/Engineering/BESSELK.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BesselYTest.php

@@ -26,7 +26,7 @@ class BesselYTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::BESSEL_PRECISION);
     }
 
-    public function providerBESSELY()
+    public function providerBESSELY(): array
     {
         return require 'tests/data/Calculation/Engineering/BESSELY.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Bin2DecTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Bin2DecTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Bin2DecTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBIN2DEC()
+    public function providerBIN2DEC(): array
     {
         return require 'tests/data/Calculation/Engineering/BIN2DEC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Bin2HexTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Bin2HexTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Bin2HexTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBIN2HEX()
+    public function providerBIN2HEX(): array
     {
         return require 'tests/data/Calculation/Engineering/BIN2HEX.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Bin2OctTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Bin2OctTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Bin2OctTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBIN2OCT()
+    public function providerBIN2OCT(): array
     {
         return require 'tests/data/Calculation/Engineering/BIN2OCT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BitAndTest.php

@@ -26,7 +26,7 @@ class BitAndTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBITAND()
+    public function providerBITAND(): array
     {
         return require 'tests/data/Calculation/Engineering/BITAND.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BitLShiftTest.php

@@ -26,7 +26,7 @@ class BitLShiftTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBITLSHIFT()
+    public function providerBITLSHIFT(): array
     {
         return require 'tests/data/Calculation/Engineering/BITLSHIFT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BitOrTest.php

@@ -26,7 +26,7 @@ class BitOrTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBITOR()
+    public function providerBITOR(): array
     {
         return require 'tests/data/Calculation/Engineering/BITOR.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BitRShiftTest.php

@@ -26,7 +26,7 @@ class BitRShiftTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBITRSHIFT()
+    public function providerBITRSHIFT(): array
     {
         return require 'tests/data/Calculation/Engineering/BITRSHIFT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/BitXorTest.php

@@ -26,7 +26,7 @@ class BitXorTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerBITXOR()
+    public function providerBITXOR(): array
     {
         return require 'tests/data/Calculation/Engineering/BITXOR.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ComplexTest.php

@@ -24,7 +24,7 @@ class ComplexTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerCOMPLEX()
+    public function providerCOMPLEX(): array
     {
         return require 'tests/data/Calculation/Engineering/COMPLEX.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ConvertUoMTest.php

@@ -54,7 +54,7 @@ class ConvertUoMTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerCONVERTUOM()
+    public function providerCONVERTUOM(): array
     {
         return require 'tests/data/Calculation/Engineering/CONVERTUOM.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Dec2BinTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Dec2BinTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Dec2BinTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerDEC2BIN()
+    public function providerDEC2BIN(): array
     {
         return require 'tests/data/Calculation/Engineering/DEC2BIN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Dec2HexTest.php

@@ -10,6 +10,9 @@ use PHPUnit\Framework\TestCase;
 
 class Dec2HexTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -41,7 +44,7 @@ class Dec2HexTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerDEC2HEX()
+    public function providerDEC2HEX(): array
     {
         return require 'tests/data/Calculation/Engineering/DEC2HEX.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Dec2OctTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Dec2OctTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Dec2OctTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerDEC2OCT()
+    public function providerDEC2OCT(): array
     {
         return require 'tests/data/Calculation/Engineering/DEC2OCT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/DeltaTest.php

@@ -24,7 +24,7 @@ class DeltaTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerDELTA()
+    public function providerDELTA(): array
     {
         return require 'tests/data/Calculation/Engineering/DELTA.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ErfCTest.php

@@ -27,7 +27,7 @@ class ErfCTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::ERF_PRECISION);
     }
 
-    public function providerERFC()
+    public function providerERFC(): array
     {
         return require 'tests/data/Calculation/Engineering/ERFC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ErfPreciseTest.php

@@ -27,7 +27,7 @@ class ErfPreciseTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::ERF_PRECISION);
     }
 
-    public function providerERFPRECISE()
+    public function providerERFPRECISE(): array
     {
         return require 'tests/data/Calculation/Engineering/ERFPRECISE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ErfTest.php

@@ -27,7 +27,7 @@ class ErfTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::ERF_PRECISION);
     }
 
-    public function providerERF()
+    public function providerERF(): array
     {
         return require 'tests/data/Calculation/Engineering/ERF.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/GeStepTest.php

@@ -24,7 +24,7 @@ class GeStepTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerGESTEP()
+    public function providerGESTEP(): array
     {
         return require 'tests/data/Calculation/Engineering/GESTEP.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Hex2BinTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Hex2BinTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Hex2BinTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerHEX2BIN()
+    public function providerHEX2BIN(): array
     {
         return require 'tests/data/Calculation/Engineering/HEX2BIN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Hex2DecTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Hex2DecTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Hex2DecTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerHEX2DEC()
+    public function providerHEX2DEC(): array
     {
         return require 'tests/data/Calculation/Engineering/HEX2DEC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Hex2OctTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Hex2OctTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Hex2OctTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerHEX2OCT()
+    public function providerHEX2OCT(): array
     {
         return require 'tests/data/Calculation/Engineering/HEX2OCT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImAbsTest.php

@@ -27,7 +27,7 @@ class ImAbsTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::COMPLEX_PRECISION);
     }
 
-    public function providerIMABS()
+    public function providerIMABS(): array
     {
         return require 'tests/data/Calculation/Engineering/IMABS.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImArgumentTest.php

@@ -27,7 +27,7 @@ class ImArgumentTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::COMPLEX_PRECISION);
     }
 
-    public function providerIMARGUMENT()
+    public function providerIMARGUMENT(): array
     {
         return require 'tests/data/Calculation/Engineering/IMARGUMENT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImConjugateTest.php

@@ -14,7 +14,7 @@ class ImConjugateTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImConjugateTest extends TestCase
         );
     }
 
-    public function providerIMCONJUGATE()
+    public function providerIMCONJUGATE(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCONJUGATE.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImCosTest.php

@@ -14,7 +14,7 @@ class ImCosTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImCosTest extends TestCase
         );
     }
 
-    public function providerIMCOS()
+    public function providerIMCOS(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCOS.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImCoshTest.php

@@ -14,7 +14,7 @@ class ImCoshTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImCoshTest extends TestCase
         );
     }
 
-    public function providerIMCOSH()
+    public function providerIMCOSH(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCOSH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImCotTest.php

@@ -14,7 +14,7 @@ class ImCotTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImCotTest extends TestCase
         );
     }
 
-    public function providerIMCOT()
+    public function providerIMCOT(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCOT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImCscTest.php

@@ -14,7 +14,7 @@ class ImCscTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImCscTest extends TestCase
         );
     }
 
-    public function providerIMCSC()
+    public function providerIMCSC(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCSC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImCschTest.php

@@ -14,7 +14,7 @@ class ImCschTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImCschTest extends TestCase
         );
     }
 
-    public function providerIMCSCH()
+    public function providerIMCSCH(): array
     {
         return require 'tests/data/Calculation/Engineering/IMCSCH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImDivTest.php

@@ -14,7 +14,7 @@ class ImDivTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -36,7 +36,7 @@ class ImDivTest extends TestCase
         );
     }
 
-    public function providerIMDIV()
+    public function providerIMDIV(): array
     {
         return require 'tests/data/Calculation/Engineering/IMDIV.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImExpTest.php

@@ -14,7 +14,7 @@ class ImExpTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImExpTest extends TestCase
         );
     }
 
-    public function providerIMEXP()
+    public function providerIMEXP(): array
     {
         return require 'tests/data/Calculation/Engineering/IMEXP.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImLnTest.php

@@ -14,7 +14,7 @@ class ImLnTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImLnTest extends TestCase
         );
     }
 
-    public function providerIMLN()
+    public function providerIMLN(): array
     {
         return require 'tests/data/Calculation/Engineering/IMLN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImLog10Test.php

@@ -14,7 +14,7 @@ class ImLog10Test extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImLog10Test extends TestCase
         );
     }
 
-    public function providerIMLOG10()
+    public function providerIMLOG10(): array
     {
         return require 'tests/data/Calculation/Engineering/IMLOG10.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImLog2Test.php

@@ -14,7 +14,7 @@ class ImLog2Test extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImLog2Test extends TestCase
         );
     }
 
-    public function providerIMLOG2()
+    public function providerIMLOG2(): array
     {
         return require 'tests/data/Calculation/Engineering/IMLOG2.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImPowerTest.php

@@ -14,7 +14,7 @@ class ImPowerTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -36,7 +36,7 @@ class ImPowerTest extends TestCase
         );
     }
 
-    public function providerIMPOWER()
+    public function providerIMPOWER(): array
     {
         return require 'tests/data/Calculation/Engineering/IMPOWER.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImProductTest.php

@@ -14,7 +14,7 @@ class ImProductTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -36,7 +36,7 @@ class ImProductTest extends TestCase
         );
     }
 
-    public function providerIMPRODUCT()
+    public function providerIMPRODUCT(): array
     {
         return require 'tests/data/Calculation/Engineering/IMPRODUCT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImRealTest.php

@@ -27,7 +27,7 @@ class ImRealTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::COMPLEX_PRECISION);
     }
 
-    public function providerIMREAL()
+    public function providerIMREAL(): array
     {
         return require 'tests/data/Calculation/Engineering/IMREAL.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSecTest.php

@@ -14,7 +14,7 @@ class ImSecTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImSecTest extends TestCase
         );
     }
 
-    public function providerIMSEC()
+    public function providerIMSEC(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSEC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSechTest.php

@@ -14,7 +14,7 @@ class ImSechTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImSechTest extends TestCase
         );
     }
 
-    public function providerIMSECH()
+    public function providerIMSECH(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSECH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSinTest.php

@@ -14,7 +14,7 @@ class ImSinTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImSinTest extends TestCase
         );
     }
 
-    public function providerIMSIN()
+    public function providerIMSIN(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSIN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSinhTest.php

@@ -14,7 +14,7 @@ class ImSinhTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImSinhTest extends TestCase
         );
     }
 
-    public function providerIMSINH()
+    public function providerIMSINH(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSINH.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSqrtTest.php

@@ -14,7 +14,7 @@ class ImSqrtTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImSqrtTest extends TestCase
         );
     }
 
-    public function providerIMSQRT()
+    public function providerIMSQRT(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSQRT.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSubTest.php

@@ -14,7 +14,7 @@ class ImSubTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -36,7 +36,7 @@ class ImSubTest extends TestCase
         );
     }
 
-    public function providerIMSUB()
+    public function providerIMSUB(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSUB.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImSumTest.php

@@ -14,7 +14,7 @@ class ImSumTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -36,7 +36,7 @@ class ImSumTest extends TestCase
         );
     }
 
-    public function providerIMSUM()
+    public function providerIMSUM(): array
     {
         return require 'tests/data/Calculation/Engineering/IMSUM.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImTanTest.php

@@ -14,7 +14,7 @@ class ImTanTest extends TestCase
     /**
      * @var ComplexAssert
      */
-    protected $complexAssert;
+    private $complexAssert;
 
     protected function setUp(): void
     {
@@ -37,7 +37,7 @@ class ImTanTest extends TestCase
         );
     }
 
-    public function providerIMTAN()
+    public function providerIMTAN(): array
     {
         return require 'tests/data/Calculation/Engineering/IMTAN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/ImaginaryTest.php

@@ -27,7 +27,7 @@ class ImaginaryTest extends TestCase
         self::assertEqualsWithDelta($expectedResult, $result, self::COMPLEX_PRECISION);
     }
 
-    public function providerIMAGINARY()
+    public function providerIMAGINARY(): array
     {
         return require 'tests/data/Calculation/Engineering/IMAGINARY.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Oct2BinTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Oct2BinTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Oct2BinTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerOCT2BIN()
+    public function providerOCT2BIN(): array
     {
         return require 'tests/data/Calculation/Engineering/OCT2BIN.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Oct2DecTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Oct2DecTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Oct2DecTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerOCT2DEC()
+    public function providerOCT2DEC(): array
     {
         return require 'tests/data/Calculation/Engineering/OCT2DEC.php';
     }

tests/PhpSpreadsheetTests/Calculation/Functions/Engineering/Oct2HexTest.php

@@ -9,6 +9,9 @@ use PHPUnit\Framework\TestCase;
 
 class Oct2HexTest extends TestCase
 {
+    /**
+     * @var string
+     */
     private $compatibilityMode;
 
     protected function setUp(): void
@@ -40,7 +43,7 @@ class Oct2HexTest extends TestCase
         self::assertEquals($expectedResult, $result);
     }
 
-    public function providerOCT2HEX()
+    public function providerOCT2HEX(): array
     {
         return require 'tests/data/Calculation/Engineering/OCT2HEX.php';
     }