Add support for 1904 dates

This commit adds support for dates using the 1904 calendar (starting 1904-01-01 00:00:00).
It also fixes some issues with the dates in 1900 calendar (which now correctly start at 1899-12-30 00:00:00).
Finally, it is now possible to have negative timestamps, representing dates before the base date (and up to 0000-01-01 00:00:00), as per the SpreadsheetML specs. Note that some versions of Excel don't support negative dates...

tests/Spout/Reader/XLSX/Helper/CellValueFormatterTest.php

@@ -15,29 +15,51 @@ class CellValueFormatterTest extends \PHPUnit_Framework_TestCase
     public function dataProviderForTestExcelDate()
     {
         return [
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 42429, '2016-02-29 00:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, '146098', '2299-12-31 00:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, -700, null],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 0, '1900-01-01 00:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 0.25, '1900-01-01 06:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 0.5, '1900-01-01 12:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 0.75, '1900-01-01 18:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 0.99999, '1900-01-01 23:59:59'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 1, '1900-01-01 00:00:00'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 59.999988425926, '1900-02-28 23:59:59'],
-            [CellValueFormatter::CELL_TYPE_NUMERIC, 60.458333333333, '1900-02-28 11:00:00'],
+            // use 1904 dates, node value, expected date as string
+
+            // 1900 calendar
+            [false, 3687.4207639, '1910-02-03 10:05:54'],
+            [false, 2.5000000, '1900-01-01 12:00:00'],
+            [false, 2958465.9999884, '9999-12-31 23:59:59'],
+            [false, 2958465.9999885, null],
+            [false, -2337.999989, '1893-08-05 00:00:01'],
+            [false, -693593, '0001-01-01 00:00:00'],
+            [false, -693593.0000001, null],
+            [false, 0, '1899-12-30 00:00:00'],
+            [false, 0.25, '1899-12-30 06:00:00'],
+            [false, 0.5, '1899-12-30 12:00:00'],
+            [false, 0.75, '1899-12-30 18:00:00'],
+            [false, 0.99999, '1899-12-30 23:59:59'],
+            [false, 1, '1899-12-31 00:00:00'],
+            [false, '3687.4207639', '1910-02-03 10:05:54'],
+
+            // 1904 calendar
+            [true, 2225.4207639, '1910-02-03 10:05:54'],
+            [true, 2.5000000, '1904-01-03 12:00:00'],
+            [true, 2957003.9999884, '9999-12-31 23:59:59'],
+            [true, 2957003.9999885, null],
+            [true, -3799.999989, '1893-08-05 00:00:01'],
+            [true, -695055, '0001-01-01 00:00:00'],
+            [true, -695055.0000001, null],
+            [true, 0, '1904-01-01 00:00:00'],
+            [true, 0.25, '1904-01-01 06:00:00'],
+            [true, 0.5, '1904-01-01 12:00:00'],
+            [true, 0.75, '1904-01-01 18:00:00'],
+            [true, 0.99999, '1904-01-01 23:59:59'],
+            [true, 1, '1904-01-02 00:00:00'],
+            [true, '2225.4207639', '1910-02-03 10:05:54'],
         ];
     }
 
     /**
      * @dataProvider dataProviderForTestExcelDate
      *
-     * @param string $cellType
+     * @param bool $shouldUse1904Dates
      * @param int|float|string $nodeValue
      * @param string|null $expectedDateAsString
      * @return void
      */
-    public function testExcelDate($cellType, $nodeValue, $expectedDateAsString)
+    public function testExcelDate($shouldUse1904Dates, $nodeValue, $expectedDateAsString)
     {
         $nodeListMock = $this->getMockBuilder('DOMNodeList')->disableOriginalConstructor()->getMock();
 
@@ -53,7 +75,7 @@ class CellValueFormatterTest extends \PHPUnit_Framework_TestCase
             ->expects($this->atLeastOnce())
             ->method('getAttribute')
             ->will($this->returnValueMap([
-                [CellValueFormatter::XML_ATTRIBUTE_TYPE, $cellType],
+                [CellValueFormatter::XML_ATTRIBUTE_TYPE, CellValueFormatter::CELL_TYPE_NUMERIC],
                 [CellValueFormatter::XML_ATTRIBUTE_STYLE_ID, 123],
             ]));
 
@@ -72,7 +94,7 @@ class CellValueFormatterTest extends \PHPUnit_Framework_TestCase
             ->with(123)
             ->will($this->returnValue(true));
 
-        $formatter = new CellValueFormatter(null, $styleManagerMock, false, new Escaper\XLSX());
+        $formatter = new CellValueFormatter(null, $styleManagerMock, false, $shouldUse1904Dates, new Escaper\XLSX());
         $result = $formatter->extractAndFormatNodeValue($nodeMock);
 
         if ($expectedDateAsString === null) {
@@ -126,7 +148,7 @@ class CellValueFormatterTest extends \PHPUnit_Framework_TestCase
             ->method('shouldFormatNumericValueAsDate')
             ->will($this->returnValue(false));
 
-        $formatter = new CellValueFormatter(null, $styleManagerMock, false, new Escaper\XLSX());
+        $formatter = new CellValueFormatter(null, $styleManagerMock, false, false, new Escaper\XLSX());
         $formattedValue = \ReflectionHelper::callMethodOnObject($formatter, 'formatNumericCellValue', $value, 0);
 
         $this->assertEquals($expectedFormattedValue, $formattedValue);
@@ -169,7 +191,7 @@ class CellValueFormatterTest extends \PHPUnit_Framework_TestCase
             ->with(CellValueFormatter::XML_NODE_INLINE_STRING_VALUE)
             ->will($this->returnValue($nodeListMock));
 
-        $formatter = new CellValueFormatter(null, null, false, new Escaper\XLSX());
+        $formatter = new CellValueFormatter(null, null, false, false, new Escaper\XLSX());
         $formattedValue = \ReflectionHelper::callMethodOnObject($formatter, 'formatInlineStringCellValue', $nodeMock);
 
         $this->assertEquals($expectedFormattedValue, $formattedValue);