Upgrade PHP and dev dependencies

/!\ Removed PHP 7.2 support /!\

- PHPUnit 8 => 9 (+ fix the tests)
- PHP-CS-Fixer 2 => 3 (+ fix the code)
- Introduced PHP stan

tests/Spout/Common/Helper/CellTypeHelperTest.php

@@ -10,7 +10,7 @@ use PHPUnit\Framework\TestCase;
 class CellTypeHelperTest extends TestCase
 {
     /**
-     * @return array
+     * @return void
      */
     public function testIsEmpty()
     {
@@ -27,7 +27,7 @@ class CellTypeHelperTest extends TestCase
     }
 
     /**
-     * @return array
+     * @return void
      */
     public function testIsNonEmptyString()
     {
@@ -44,7 +44,7 @@ class CellTypeHelperTest extends TestCase
     }
 
     /**
-     * @return array
+     * @return void
      */
     public function testIsNumeric()
     {
@@ -66,7 +66,7 @@ class CellTypeHelperTest extends TestCase
     }
 
     /**
-     * @return array
+     * @return void
      */
     public function testIsBoolean()
     {

tests/Spout/Reader/CSV/SpoutTestStream.php

@@ -9,10 +9,10 @@ namespace Box\Spout\Reader\CSV;
  */
 class SpoutTestStream
 {
-    const CLASS_NAME = __CLASS__;
+    public const CLASS_NAME = __CLASS__;
 
-    const PATH_TO_CSV_RESOURCES = 'tests/resources/csv/';
-    const CSV_EXTENSION = '.csv';
+    public const PATH_TO_CSV_RESOURCES = 'tests/resources/csv/';
+    public const CSV_EXTENSION = '.csv';
 
     /** @var int */
     private $position;

tests/Spout/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyFactoryTest.php

@@ -46,7 +46,7 @@ class CachingStrategyFactoryTest extends TestCase
         $factoryStub->method('getMemoryLimitInKB')->willReturn($memoryLimitInKB);
 
         $tempFolder = sys_get_temp_dir();
-        $helperFactory = new HelperFactory($factoryStub);
+        $helperFactory = new HelperFactory();
         $strategy = $factoryStub->createBestCachingStrategy($sharedStringsUniqueCount, $tempFolder, $helperFactory);
 
         $fullExpectedStrategyClassName = 'Box\Spout\Reader\XLSX\Manager\SharedStringsCaching\\' . $expectedStrategyClassName;

tests/Spout/ReflectionHelper.php

@@ -62,7 +62,7 @@ class ReflectionHelper
 
         // to prevent side-effects in later tests, we need to remember the original value and reset it on tear down
         // @NOTE: we need to check isset in case the original value was null or array()
-        if ($saveOriginalValue && (!isset(self::$privateVarsToReset[$class]) || !isset(self::$privateVarsToReset[$class][$name]))) {
+        if ($saveOriginalValue && (!isset(self::$privateVarsToReset[$class]) || !isset(self::$privateVarsToReset[$class][$valueName]))) {
             self::$privateVarsToReset[$class][$valueName] = $reflectionProperty->getValue();
         }
         $reflectionProperty->setValue($value);

tests/Spout/Writer/ODS/SheetTest.php

@@ -95,7 +95,7 @@ class SheetTest extends TestCase
     /**
      * @param string $fileName
      * @param string $sheetName
-     * @return Sheet
+     * @return void
      */
     private function writeDataAndReturnSheetWithCustomName($fileName, $sheetName)
     {

tests/Spout/Writer/ODS/WriterTest.php

@@ -132,7 +132,7 @@ class WriterTest extends TestCase
             $writer->addRows($dataRows);
             $this->fail('Exception should have been thrown');
         } catch (SpoutException $e) {
-            $this->assertFileNotExists($fileName, 'Output file should have been deleted');
+            $this->assertFileDoesNotExist($fileName, 'Output file should have been deleted');
 
             $numFiles = iterator_count(new \FilesystemIterator($tempFolderPath, \FilesystemIterator::SKIP_DOTS));
             $this->assertEquals(0, $numFiles, 'All temp files should have been deleted');

tests/Spout/Writer/XLSX/WriterTest.php

@@ -163,7 +163,7 @@ class WriterTest extends TestCase
             $writer->addRows($dataRows);
             $this->fail('Exception should have been thrown');
         } catch (SpoutException $e) {
-            $this->assertFileNotExists($fileName, 'Output file should have been deleted');
+            $this->assertFileDoesNotExist($fileName, 'Output file should have been deleted');
 
             $numFiles = iterator_count(new \FilesystemIterator($tempFolderPath, \FilesystemIterator::SKIP_DOTS));
             $this->assertEquals(0, $numFiles, 'All temp files should have been deleted');