Fix for #1612 - SLK Long File Name (#1706)

Issue has been marked stale, but ...
Sylk read sets worksheet title to filename (minus .slk).
If that is >31 characters, PhpSpreadsheet throws Exception.
This change truncates sheet title, as Excel does, to 31 characters.

Author: oleibman

src/PhpSpreadsheet/Reader/Slk.php

@@ -9,6 +9,7 @@
 use PhpOffice\PhpSpreadsheet\Shared\StringHelper;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
 use PhpOffice\PhpSpreadsheet\Style\Border;
+use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 
 class Slk extends BaseReader
 {
@@ -516,7 +517,7 @@ public function loadIntoExisting($pFilename, Spreadsheet $spreadsheet)
             $spreadsheet->createSheet();
         }
         $spreadsheet->setActiveSheetIndex($this->sheetIndex);
-        $spreadsheet->getActiveSheet()->setTitle(basename($pFilename, '.slk'));
+        $spreadsheet->getActiveSheet()->setTitle(substr(basename($pFilename, '.slk'), 0, Worksheet::SHEET_TITLE_MAXIMUM_LENGTH));
 
         // Loop through file
         $column = $row = '';

tests/PhpSpreadsheetTests/Reader/SlkTest.php

@@ -4,6 +4,7 @@
 
 use PhpOffice\PhpSpreadsheet\Reader\Exception as ReaderException;
 use PhpOffice\PhpSpreadsheet\Reader\Slk;
+use PhpOffice\PhpSpreadsheet\Shared\File;
 use PhpOffice\PhpSpreadsheet\Style\Border;
 use PhpOffice\PhpSpreadsheet\Style\Fill;
 use PhpOffice\PhpSpreadsheet\Style\Font;
@@ -12,6 +13,16 @@ class SlkTest extends \PHPUnit\Framework\TestCase
 {
     private static $testbook = __DIR__ . '/../../../samples/templates/SylkTest.slk';
 
+    private $filename = '';
+
+    protected function teardown(): void
+    {
+        if ($this->filename) {
+            unlink($this->filename);
+            $this->filename = '';
+        }
+    }
+
     public function testInfo(): void
     {
         $reader = new Slk();
@@ -131,4 +142,17 @@ public function testSheetIndex(): void
 
         self::assertEquals('FFFF0000', $sheet->getCell('A1')->getStyle()->getFont()->getColor()->getARGB());
     }
+
+    public function testLongName(): void
+    {
+        $contents = file_get_contents(self::$testbook);
+        $this->filename = File::sysGetTempDir()
+            . '/123456789a123456789b123456789c12345.slk';
+        file_put_contents($this->filename, $contents);
+        $reader = new Slk();
+        $spreadsheet = $reader->load($this->filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertEquals('123456789a123456789b123456789c1', $sheet->getTitle());
+        self::assertEquals('FFFF0000', $sheet->getCell('A1')->getStyle()->getFont()->getColor()->getARGB());
+    }
 }