diff --git a/.travis.yml b/.travis.yml
index 9e90442..d4306c9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,7 +12,7 @@ install:
 
 script:
   - mkdir -p build/logs
-  - php vendor/bin/phpunit --coverage-clover build/logs/clover.xml --coverage-text
+  - php vendor/bin/phpunit --coverage-clover build/logs/clover.xml
 
 after_script:
   - if [[ $TRAVIS_PHP_VERSION != 'hhvm' && $TRAVIS_PHP_VERSION != '7.0' ]]; then php vendor/bin/ocular code-coverage:upload --format=php-clover build/logs/clover.xml; fi
diff --git a/src/Spout/Common/Helper/GlobalFunctionsHelper.php b/src/Spout/Common/Helper/GlobalFunctionsHelper.php
index feeb782..47ed052 100644
--- a/src/Spout/Common/Helper/GlobalFunctionsHelper.php
+++ b/src/Spout/Common/Helper/GlobalFunctionsHelper.php
@@ -160,7 +160,7 @@ class GlobalFunctionsHelper
      * @see file_get_contents()
      *
      * @param string $filePath
-     * @return bool
+     * @return string
      */
     public function file_get_contents($filePath)
     {
diff --git a/src/Spout/Reader/CSV/RowIterator.php b/src/Spout/Reader/CSV/RowIterator.php
index 2316fa7..ffb533f 100644
--- a/src/Spout/Reader/CSV/RowIterator.php
+++ b/src/Spout/Reader/CSV/RowIterator.php
@@ -111,9 +111,9 @@ class RowIterator implements IteratorInterface
         if (!$this->hasReachedEndOfFile) {
             do {
                $lineData = $this->globalFunctionsHelper->fgetcsv($this->filePointer, 0, $this->fieldDelimiter, $this->fieldEnclosure);
-           } while ($lineData && $this->isEmptyLine($lineData));
+           } while ($lineData === false || ($lineData !== null && $this->isEmptyLine($lineData)));
 
-            if ($lineData !== null) {
+            if ($lineData !== false && $lineData !== null) {
                 $this->rowDataBuffer = $lineData;
                 $this->numReadRows++;
             }
@@ -133,7 +133,7 @@ class RowIterator implements IteratorInterface
      * Return the current element from the buffer
      * @link http://php.net/manual/en/iterator.current.php
      *
-     * @return array
+     * @return array|null
      */
     public function current()
     {
diff --git a/src/Spout/Reader/XLSX/Helper/SharedStringsCaching/FileBasedStrategy.php b/src/Spout/Reader/XLSX/Helper/SharedStringsCaching/FileBasedStrategy.php
index 6670bfe..9f1f19f 100644
--- a/src/Spout/Reader/XLSX/Helper/SharedStringsCaching/FileBasedStrategy.php
+++ b/src/Spout/Reader/XLSX/Helper/SharedStringsCaching/FileBasedStrategy.php
@@ -26,6 +26,9 @@ class FileBasedStrategy implements CachingStrategyInterface
     /** @var \Box\Spout\Common\Helper\FileSystemHelper Helper to perform file system operations */
     protected $fileSystemHelper;
 
+    /** @var string Temporary folder where the temporary files will be created */
+    protected $tempFolder;
+
     /**
      * @var int Maximum number of strings that can be stored in one temp file
      * @see CachingStrategyFactory::MAX_NUM_STRINGS_PER_TEMP_FILE
@@ -42,7 +45,7 @@ class FileBasedStrategy implements CachingStrategyInterface
     protected $inMemoryTempFilePath;
 
     /**
-     * @var string Contents of the temporary file that was last read
+     * @var array Contents of the temporary file that was last read
      * @see CachingStrategyFactory::MAX_NUM_STRINGS_PER_TEMP_FILE
      */
     protected $inMemoryTempFileContents;
diff --git a/src/Spout/Reader/XLSX/Helper/SheetHelper.php b/src/Spout/Reader/XLSX/Helper/SheetHelper.php
index 3cbe9cb..a3431ae 100644
--- a/src/Spout/Reader/XLSX/Helper/SheetHelper.php
+++ b/src/Spout/Reader/XLSX/Helper/SheetHelper.php
@@ -72,8 +72,9 @@ class SheetHelper
 
         // find all nodes defining a sheet
         $sheetNodes = $contentTypesAsXMLElement->xpath('//ns:Override[@ContentType="' . self::OVERRIDE_CONTENT_TYPES_ATTRIBUTE . '"]');
+        $numSheetNodes = count($sheetNodes);
 
-        for ($i = 0; $i < count($sheetNodes); $i++) {
+        for ($i = 0; $i < $numSheetNodes; $i++) {
             $sheetNode = $sheetNodes[$i];
             $sheetDataXMLFilePath = (string) $sheetNode->attributes()->PartName;
 
@@ -95,7 +96,7 @@ class SheetHelper
      *
      * @param string $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
      * @param int $sheetIndexZeroBased Index of the sheet, based on order in [Content_Types].xml (zero-based)
-     * @return \Box\Spout\Reader\Sheet Sheet instance
+     * @return \Box\Spout\Reader\XLSX\Sheet Sheet instance
      */
     protected function getSheetFromXML($sheetDataXMLFilePath, $sheetIndexZeroBased)
     {
@@ -136,7 +137,7 @@ class SheetHelper
      * Returns the default name of the sheet whose data is located
      * at the given path.
      *
-     * @param $sheetDataXMLFilePath
+     * @param string $sheetDataXMLFilePath Path of the sheet data XML file
      * @return string The default sheet name
      */
     protected function getDefaultSheetName($sheetDataXMLFilePath)
diff --git a/src/Spout/Reader/XLSX/Sheet.php b/src/Spout/Reader/XLSX/Sheet.php
index e2eebec..9510ecd 100644
--- a/src/Spout/Reader/XLSX/Sheet.php
+++ b/src/Spout/Reader/XLSX/Sheet.php
@@ -32,7 +32,7 @@ class Sheet implements SheetInterface
      * @param int $sheetIndex Index of the sheet, based on order of creation (zero-based)
      * @param string $sheetName Name of the sheet
      */
-    function __construct($filePath, $sheetDataXMLFilePath, $sharedStringsHelper, $sheetId, $sheetIndex, $sheetName)
+    public function __construct($filePath, $sheetDataXMLFilePath, $sharedStringsHelper, $sheetId, $sheetIndex, $sheetName)
     {
         $this->rowIterator = new RowIterator($filePath, $sheetDataXMLFilePath, $sharedStringsHelper);
         $this->id = $sheetId;
diff --git a/src/Spout/Writer/XLSX/Helper/SharedStringsHelper.php b/src/Spout/Writer/XLSX/Helper/SharedStringsHelper.php
index c78364c..8a544f9 100644
--- a/src/Spout/Writer/XLSX/Helper/SharedStringsHelper.php
+++ b/src/Spout/Writer/XLSX/Helper/SharedStringsHelper.php
@@ -25,6 +25,9 @@ EOD;
      */
     const DEFAULT_STRINGS_COUNT_PART = 'count="9999999999999" uniqueCount="9999999999999"';
 
+    /** @var resource Pointer to the sharedStrings.xml file */
+    protected $sharedStringsFilePointer;
+
     /** @var int Number of shared strings already written */
     protected $numSharedStrings = 0;
 
diff --git a/src/Spout/Writer/XLSX/Sheet.php b/src/Spout/Writer/XLSX/Sheet.php
index 46380a2..858adcd 100644
--- a/src/Spout/Writer/XLSX/Sheet.php
+++ b/src/Spout/Writer/XLSX/Sheet.php
@@ -21,7 +21,7 @@ class Sheet
     /**
      * @param int $sheetIndex Index of the sheet, based on order of creation (zero-based)
      */
-    function __construct($sheetIndex)
+    public function __construct($sheetIndex)
     {
         $this->index = $sheetIndex;
         $this->name = self::DEFAULT_SHEET_NAME_PREFIX . ($sheetIndex + 1);
diff --git a/tests/Spout/Reader/XLSX/ReaderTest.php b/tests/Spout/Reader/XLSX/ReaderTest.php
index 8c8376b..0037ca9 100644
--- a/tests/Spout/Reader/XLSX/ReaderTest.php
+++ b/tests/Spout/Reader/XLSX/ReaderTest.php
@@ -93,6 +93,9 @@ class ReaderTest extends \PHPUnit_Framework_TestCase
      */
     public function testReadShouldSupportAllCellTypes()
     {
+        // make sure dates are always created with the same timezone
+        date_default_timezone_set('UTC');
+
         $allRows = $this->getAllRowsForFile('sheet_with_all_cell_types.xlsx');
 
         $expectedRows = [