Better date support

Although Excel has a Date type, older Excel versions use numeric values to store dates.
The value represents the number of days since Jan 1st, 1900.
The only way to tell if the value is a number or a date is to look at the styles.xml and check if the cell has date formatting.

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

@@ -0,0 +1,134 @@
+<?php
+
+namespace Box\Spout\Reader\XLSX\Helper;
+
+/**
+ * Class StyleHelperTest
+ *
+ * @package Box\Spout\Reader\XLSX\Helper
+ */
+class StyleHelperTest extends \PHPUnit_Framework_TestCase
+{
+
+    /**
+     * @param array $styleAttributes
+     * @param array|void $customNumberFormats
+     * @return StyleHelper
+     */
+    private function getStyleHelperMock($styleAttributes, $customNumberFormats = [])
+    {
+        /** @var StyleHelper $styleHelper */
+        $styleHelper = $this->getMockBuilder('\Box\Spout\Reader\XLSX\Helper\StyleHelper')
+                            ->setMethods(['getCustomNumberFormats', 'getStylesAttributes'])
+                            ->disableOriginalConstructor()
+                            ->getMock();
+
+        $styleHelper->method('getStylesAttributes')->willReturn($styleAttributes);
+        $styleHelper->method('getCustomNumberFormats')->willReturn($customNumberFormats);
+
+        return $styleHelper;
+    }
+
+    /**
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWithDefaultStyle()
+    {
+        $styleHelper = $this->getStyleHelperMock([]);
+        $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(0);
+        $this->assertFalse($shouldFormatAsDate);
+    }
+
+    /**
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWhenStyleIdNotListed()
+    {
+        $styleHelper = $this->getStyleHelperMock([['applyNumberFormat' => true]]);
+        $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(1);
+        $this->assertFalse($shouldFormatAsDate);
+    }
+
+    /**
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWhenShouldNotApplyNumberFormat()
+    {
+        $styleHelper = $this->getStyleHelperMock([[], ['applyNumberFormat' => false]]);
+        $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(1);
+        $this->assertFalse($shouldFormatAsDate);
+    }
+
+    /**
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWithBuiltinDateFormats()
+    {
+        $builtinNumFmtIdsForDate = [14, 15, 16, 17, 18, 19, 20, 21, 22, 45, 46, 47];
+
+        foreach ($builtinNumFmtIdsForDate as $builtinNumFmtIdForDate) {
+            $styleHelper = $this->getStyleHelperMock([[], ['applyNumberFormat' => true, 'numFmtId' => $builtinNumFmtIdForDate]]);
+            $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(1);
+
+            $this->assertTrue($shouldFormatAsDate);
+        }
+    }
+
+    /**
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWhenCustomNumberFormatNotFound()
+    {
+        $styleHelper = $this->getStyleHelperMock([[], ['applyNumberFormat' => true, 'numFmtId' => 165]], [166 => []]);
+        $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(1);
+
+        $this->assertFalse($shouldFormatAsDate);
+    }
+
+    /**
+     * @return array
+     */
+    public function dataProviderForCustomDateFormats()
+    {
+        return [
+            // number format, expectedResult
+            ['[$-409]dddd\,\ mmmm\ d\,\ yy', true],
+            ['[$-409]d\-mmm\-yy;@', true],
+            ['[$-409]d\-mmm\-yyyy;@', true],
+            ['mm/dd/yy;@', true],
+            ['[$-F800]dddd\,\ mmmm\ dd\,\ yyyy', true],
+            ['m/d;@', true],
+            ['m/d/yy;@', true],
+            ['[$-409]d\-mmm;@', true],
+            ['[$-409]dd\-mmm\-yy;@', true],
+            ['[$-409]mmm\-yy;@', true],
+            ['[$-409]mmmm\-yy;@', true],
+            ['[$-409]mmmm\ d\,\ yyyy;@', true],
+            ['[$-409]m/d/yy\ h:mm\ AM/PM;@', true],
+            ['m/d/yy\ h:mm;@', true],
+            ['[$-409]mmmmm;@', true],
+            ['[$-409]mmmmm\-yy;@', true],
+            ['m/d/yyyy;@', true],
+            ['[$-409]m/d/yy\--h:mm;@', true],
+            ['GENERAL', false],
+            ['\ma\yb\e', false],
+            ['[Red]foo;', false],
+        ];
+    }
+
+    /**
+     * @dataProvider dataProviderForCustomDateFormats
+     *
+     * @param string $numberFormat
+     * @param bool $expectedResult
+     * @return void
+     */
+    public function testShouldFormatNumericValueAsDateWithCustomDateFormats($numberFormat, $expectedResult)
+    {
+        $numFmtId = 165;
+        $styleHelper = $this->getStyleHelperMock([[], ['applyNumberFormat' => true, 'numFmtId' => $numFmtId]], [$numFmtId => $numberFormat]);
+        $shouldFormatAsDate = $styleHelper->shouldFormatNumericValueAsDate(1);
+
+        $this->assertEquals($expectedResult, $shouldFormatAsDate);
+    }
+}

tests/Spout/Reader/XLSX/ReaderTest.php

@@ -113,6 +113,52 @@ class ReaderTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals($expectedRows, $allRows);
     }
 
+    /**
+     * @return void
+     */
+    public function testReadShouldSupportNumericTimestampFormattedDifferentlyAsDate()
+    {
+        // make sure dates are always created with the same timezone
+        date_default_timezone_set('UTC');
+
+        $allRows = $this->getAllRowsForFile('sheet_with_same_numeric_value_date_formatted_differently.xlsx');
+
+        $expectedDate = \DateTime::createFromFormat('Y-m-d H:i:s', '2015-01-01 00:00:00');
+        $expectedRows = [
+            array_fill(0, 10, $expectedDate),
+            array_fill(0, 10, $expectedDate),
+            array_fill(0, 10, $expectedDate),
+            array_merge(array_fill(0, 7, $expectedDate), ['', '', '']),
+        ];
+
+        $this->assertEquals($expectedRows, $allRows);
+    }
+
+    /**
+     * @return void
+     */
+    public function testReadShouldSupportDifferentDatesAsNumericTimestamp()
+    {
+        // make sure dates are always created with the same timezone
+        date_default_timezone_set('UTC');
+
+        $allRows = $this->getAllRowsForFile('sheet_with_different_numeric_value_dates.xlsx');
+
+        $expectedRows = [
+            [
+                \DateTime::createFromFormat('Y-m-d H:i:s', '2015-09-01 00:00:00'),
+                \DateTime::createFromFormat('Y-m-d H:i:s', '2015-09-02 00:00:00'),
+                \DateTime::createFromFormat('Y-m-d H:i:s', '2015-09-01 22:23:00'),
+            ],
+            [
+                \DateTime::createFromFormat('Y-m-d H:i:s', '1900-02-28 23:59:59'),
+                \DateTime::createFromFormat('Y-m-d H:i:s', '1900-03-01 00:00:00'),
+                \DateTime::createFromFormat('Y-m-d H:i:s', '1900-02-28 11:00:00'), // 1900-02-29 should be converted to 1900-02-28
+            ]
+        ];
+        $this->assertEquals($expectedRows, $allRows);
+    }
+
     /**
      * @return void
      */