Refactor ISO data type validation from cell to shared date; add extra checks for invalid dates; and appropriate unit tests

src/PhpSpreadsheet/Cell/Cell.php

@@ -2,7 +2,6 @@
 
 namespace PhpOffice\PhpSpreadsheet\Cell;
 
-use DateTime;
 use PhpOffice\PhpSpreadsheet\Calculation\Calculation;
 use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
 use PhpOffice\PhpSpreadsheet\Collection\Cells;
@@ -240,18 +239,7 @@ class Cell
 
                 break;
             case DataType::TYPE_ISO_DATE:
-                if (!is_string($value)) {
-                    throw new Exception('Non-string supplied for datatype Date');
-                }
-                $date = new DateTime($value);
-                $newValue = SharedDate::PHPToExcel($date);
-                if ($newValue === false) {
-                    throw new Exception("Invalid string $value supplied for datatype Date");
-                }
-                if (preg_match('/^\\d\\d:\\d\\d:\\d\\d/', $value) == 1) {
-                    $newValue = fmod($newValue, 1.0);
-                }
-                $this->value = $newValue;
+                $this->value = SharedDate::convertIsoDate($value);
                 $dataType = DataType::TYPE_NUMERIC;
 
                 break;

src/PhpSpreadsheet/Shared/Date.php

@@ -9,7 +9,9 @@ use PhpOffice\PhpSpreadsheet\Calculation\DateTimeExcel;
 use PhpOffice\PhpSpreadsheet\Calculation\Functions;
 use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
 use PhpOffice\PhpSpreadsheet\Cell\Cell;
+use PhpOffice\PhpSpreadsheet\Exception;
 use PhpOffice\PhpSpreadsheet\Exception as PhpSpreadsheetException;
+use PhpOffice\PhpSpreadsheet\Shared\Date as SharedDate;
 use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
 
 class Date
@@ -158,6 +160,36 @@ class Date
         throw new PhpSpreadsheetException('Invalid timezone');
     }
 
+    /**
+     * @param mixed $value
+     *
+     * @return float|int
+     */
+    public static function convertIsoDate($value)
+    {
+        if (!is_string($value)) {
+            throw new Exception('Non-string value supplied for Iso Date conversion');
+        }
+
+        $date = new DateTime($value);
+        $dateErrors = DateTime::getLastErrors();
+
+        if (is_array($dateErrors) && ($dateErrors['warning_count'] > 0 || $dateErrors['error_count'] > 0)) {
+            throw new Exception("Invalid string $value supplied for datatype Date");
+        }
+
+        $newValue = SharedDate::PHPToExcel($date);
+        if ($newValue === false) {
+            throw new Exception("Invalid string $value supplied for datatype Date");
+        }
+
+        if (preg_match('/^\\d\\d:\\d\\d:\\d\\d/', $value) == 1) {
+            $newValue = fmod($newValue, 1.0);
+        }
+
+        return $newValue;
+    }
+
     /**
      * Convert a MS serialized datetime value from Excel to a PHP Date/Time object.
      *

tests/PhpSpreadsheetTests/Cell/CellTest.php

@@ -2,6 +2,7 @@
 
 namespace PhpOffice\PhpSpreadsheetTests\Cell;
 
+use PhpOffice\PhpSpreadsheet\Cell\DataType;
 use PhpOffice\PhpSpreadsheet\Exception;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
 use PhpOffice\PhpSpreadsheet\Style\Color;
@@ -33,6 +34,19 @@ class CellTest extends TestCase
         return require 'tests/data/Cell/SetValueExplicit.php';
     }
 
+    public function testInvalidIsoDateSetValueExplicit(): void
+    {
+        $spreadsheet = new Spreadsheet();
+        $cell = $spreadsheet->getActiveSheet()->getCell('A1');
+
+        $dateValue = '2022-02-29'; // Invalid leap year
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage("Invalid string {$dateValue} supplied for datatype Date");
+        $cell->setValueExplicit($dateValue, DataType::TYPE_ISO_DATE);
+
+        $spreadsheet->disconnectWorksheets();
+    }
+
     /**
      * @dataProvider providerSetValueExplicitException
      *

tests/PhpSpreadsheetTests/Shared/DateTest.php

@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheetTests\Shared;
 
 use DateTimeZone;
+use PhpOffice\PhpSpreadsheet\Exception;
 use PhpOffice\PhpSpreadsheet\Shared\Date;
 use PhpOffice\PhpSpreadsheet\Style\NumberFormat;
 use PHPUnit\Framework\TestCase;
@@ -209,6 +210,15 @@ class DateTest extends TestCase
         return require 'tests/data/Shared/Date/ExcelToTimestamp1900Timezone.php';
     }
 
+    public function testConvertIsoDateError(): void
+    {
+        Date::setExcelCalendar(Date::CALENDAR_WINDOWS_1900);
+
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('Non-string value supplied for Iso Date conversion');
+        Date::convertIsoDate(false);
+    }
+
     public function testVarious(): void
     {
         Date::setDefaultTimeZone('UTC');

tests/data/Cell/SetValueExplicit.php

@@ -1,5 +1,6 @@
 <?php
 
+use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
 use PhpOffice\PhpSpreadsheet\Cell\DataType;
 
 return [
@@ -39,12 +40,27 @@ return [
         DataType::TYPE_NUMERIC,
     ],
     [
-        '#DIV/0!',
+        44613.43090277778,
+        '2022-02-21 10:20:30',
+        DataType::TYPE_ISO_DATE,
+    ],
+    [
+        44613.0,
+        '2022-02-21',
+        DataType::TYPE_ISO_DATE,
+    ],
+    [
+        -30879.0,
+        '1815-06-15',               // Dates outside the Excel Range should fail really
+        DataType::TYPE_ISO_DATE,
+    ],
+    [
+        ExcelError::DIV0(),
         '#DIV/0!',
         DataType::TYPE_ERROR,
     ],
     [
-        '#NULL!',
+        ExcelError::null(),
         'NOT A VALID ERROR TYPE VALUE',
         DataType::TYPE_ERROR,
     ],