Add Ability to Suppress Mac Line Ending Check for CSV Reader (#2623)

With the deprecation of `auto_detect_line_endings` in Php8.1, there have been some tickets (issue #2609 and PR #2438). Although the deprecation message is suppressed, users with a homegrown error handler may still see it. I am not very concerned about that symptom, but I imagine that there will be more similar tickets in future. This PR adds a new property/method to Reader/CSV to allow the user to avoid the deprecated code, at the negligible cost of being unable to read a CSV with Mac line endings even on a Php version that could support it.

docs/topics/reading-and-writing-to-file.md

@@ -544,6 +544,25 @@ $reader->setSheetIndex(5);
 $reader->loadIntoExisting("05featuredemo.csv", $spreadsheet);
 ```
 
+#### Line endings
+
+Line endings for Unix (`\n`) and Windows (`\r\n`) are supported.
+
+Mac line endings (`\r`) are supported as long as PHP itself
+supports them, which it does through release 8.0.
+Support for Mac line endings is deprecated for 8.1,
+and is scheduled to remain deprecated for all later PHP8 releases;
+PhpSpreadsheet will continue to support them for 8.*.
+Support is scheduled to be dropped with release 9;
+PhpSpreadsheet will then no longer handle CSV files
+with Mac line endings correctly.
+
+You can suppress testing for Mac line endings as follows:
+```php
+$reader = new \PhpOffice\PhpSpreadsheet\Reader\Csv();
+$reader->setTestAutoDetect(false);
+```
+
 ### \PhpOffice\PhpSpreadsheet\Writer\Csv
 
 #### Writing a CSV file

src/PhpSpreadsheet/Reader/Csv.php

@@ -84,6 +84,13 @@ class Csv extends BaseReader
      */
     private static $constructorCallback;
 
+    /**
+     * Attempt autodetect line endings (deprecated after PHP8.1)?
+     *
+     * @var bool
+     */
+    private $testAutodetect = true;
+
     /**
      * Create a new CSV Reader instance.
      */
@@ -269,10 +276,15 @@ class Csv extends BaseReader
         }
     }
 
-    private static function setAutoDetect(?string $value): ?string
+    public function setTestAutoDetect(bool $value): void
+    {
+        $this->testAutodetect = $value;
+    }
+
+    private function setAutoDetect(?string $value): ?string
     {
         $retVal = null;
-        if ($value !== null) {
+        if ($value !== null && $this->testAutodetect) {
             $retVal2 = @ini_set('auto_detect_line_endings', $value);
             if (is_string($retVal2)) {
                 $retVal = $retVal2;
@@ -288,7 +300,7 @@ class Csv extends BaseReader
     public function loadIntoExisting(string $filename, Spreadsheet $spreadsheet): Spreadsheet
     {
         // Deprecated in Php8.1
-        $iniset = self::setAutoDetect('1');
+        $iniset = $this->setAutoDetect('1');
 
         // Open file
         $this->openFileOrMemory($filename);
@@ -339,7 +351,7 @@ class Csv extends BaseReader
         // Close file
         fclose($fileHandle);
 
-        self::setAutoDetect($iniset);
+        $this->setAutoDetect($iniset);
 
         // Return
         return $spreadsheet;

tests/PhpSpreadsheetTests/Reader/Csv/CsvLineEndingTest.php

@@ -36,6 +36,31 @@ class CsvLineEndingTest extends TestCase
         $spreadsheet->disconnectWorksheets();
     }
 
+    /**
+     * @dataProvider providerEndings
+     */
+    public function testEndingsNoDetect(string $ending): void
+    {
+        $this->tempFile = $filename = File::temporaryFilename();
+        $data = ['123', '456', '789'];
+        file_put_contents($filename, implode($ending, $data));
+        $reader = new Csv();
+        $reader->setTestAutoDetect(false);
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        if ($ending === "\r") {
+            // Can't handle Mac line endings without autoDetect
+            self::assertEquals(implode("\n", $data), $sheet->getCell('A1')->getValue());
+            self::assertNull($sheet->getCell('A2')->getValue());
+            self::assertNull($sheet->getCell('A3')->getValue());
+        } else {
+            self::assertEquals($data[0], $sheet->getCell('A1')->getValue());
+            self::assertEquals($data[1], $sheet->getCell('A2')->getValue());
+            self::assertEquals($data[2], $sheet->getCell('A3')->getValue());
+        }
+        $spreadsheet->disconnectWorksheets();
+    }
+
     public function providerEndings(): array
     {
         return [