[Serializer] CsvEncoder to escape values starting with line feed when escape formulas is enabled

Author: Peter Mead

Encoder/CsvEncoder.php

@@ -39,7 +39,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
 
     private const UTF8_BOM = "\xEF\xBB\xBF";
 
-    private const FORMULAS_START_CHARACTERS = ['=', '-', '+', '@', "\t", "\r"];
+    private const FORMULAS_START_CHARACTERS = ['=', '-', '+', '@', "\t", "\r", "\n"];
 
     private array $defaultContext = [
         self::DELIMITER_KEY => ',',

Tests/Encoder/CsvEncoderTest.php

@@ -310,6 +310,15 @@ public function testEncodeFormulas()
             $this->encoder->encode(["\ttab"], 'csv')
         );
 
+        $this->assertSame(<<<'CSV'
+            0
+            "'
+            line feed"
+
+            CSV,
+            $this->encoder->encode(["\nline feed"], 'csv')
+        );
+
         $this->assertSame(<<<'CSV'
             0
             "'=1+2"";=1+2"
@@ -438,6 +447,17 @@ public function testEncodeFormulasWithSettingsPassedInContext()
             ])
         );
 
+        $this->assertSame(<<<'CSV'
+            0
+            "'
+            line feed"
+
+            CSV,
+            $this->encoder->encode(["\nline feed"], 'csv', [
+                CsvEncoder::ESCAPE_FORMULAS_KEY => true,
+            ])
+        );
+
         $this->assertSame(<<<'CSV'
             0
             "'=1+2"";=1+2"