diff --git a/.codeclimate.yml b/.codeclimate.yml
index 641e74d..99a2ccf 100644
--- a/.codeclimate.yml
+++ b/.codeclimate.yml
@@ -2,6 +2,9 @@ version: "2"
 plugins:
   phpmd:
     enabled: true
+    checks:
+      CleanCode/StaticAccess:
+        enabled: false
   phpcodesniffer:
     enabled: true
   sonar-php:
diff --git a/.travis.yml b/.travis.yml
index 16ba0c7..74ff91c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,7 +2,10 @@ language: php
 php:
   - 5.6
   - 7.0
-  - hhvm
+  - 7.1
+  - 7.2
+  - 7.3
+  - 7.4
 
 before_script: 
   - composer install
diff --git a/composer.json b/composer.json
index f18e95e..812d5d3 100644
--- a/composer.json
+++ b/composer.json
@@ -29,6 +29,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^5.7",
-        "squizlabs/php_codesniffer": "^3.2"
+        "squizlabs/php_codesniffer": "^3.2",
+        "ext-json": "*"
     }
 }
diff --git a/src/CsvReader.php b/src/CsvReader.php
index a3dc7aa..ee1fa9a 100644
--- a/src/CsvReader.php
+++ b/src/CsvReader.php
@@ -111,29 +111,10 @@ protected function openCsvFile($fileName)
      */
     protected function detectLineBreak()
     {
-        rewind($this->getFilePointer());
-        $sample = fread($this->getFilePointer(), 10000);
-
-        $possibleLineBreaks = [
-            "\r\n", // win
-            "\r", // mac
-            "\n", // unix
-        ];
-
-        $lineBreaksPositions = [];
-        foreach ($possibleLineBreaks as $lineBreak) {
-            $position = strpos($sample, $lineBreak);
-            if ($position === false) {
-                continue;
-            }
-            $lineBreaksPositions[$lineBreak] = $position;
-        }
-
-
-        asort($lineBreaksPositions);
-        reset($lineBreaksPositions);
+        @rewind($this->getFilePointer());
+        $sample = @fread($this->getFilePointer(), 10000);
 
-        return empty($lineBreaksPositions) ? "\n" : key($lineBreaksPositions);
+        return LineBreaksHelper::detectLineBreaks($sample, $this->getEnclosure(), $this->getEscapedBy());
     }
 
     /**
@@ -148,7 +129,7 @@ protected function readLine()
         // allow empty enclosure hack
         $enclosure = !$this->getEnclosure() ? chr(0) : $this->getEnclosure();
         $escapedBy = !$this->getEscapedBy() ? chr(0) : $this->getEscapedBy();
-        return fgetcsv($this->getFilePointer(), null, $this->getDelimiter(), $enclosure, $escapedBy);
+        return @fgetcsv($this->getFilePointer(), null, $this->getDelimiter(), $enclosure, $escapedBy);
     }
 
     /**
diff --git a/src/CsvWriter.php b/src/CsvWriter.php
index 45c683d..454a571 100644
--- a/src/CsvWriter.php
+++ b/src/CsvWriter.php
@@ -90,7 +90,7 @@ public function writeRow(array $row)
                 "Cannot write to CSV file " . $this->fileName .
                 ($ret === false && error_get_last() ? 'Error: ' . error_get_last()['message'] : '') .
                 ' Return: ' . json_encode($ret) .
-                ' To write: ' . strlen($str) . ' Written: ' . $ret,
+                ' To write: ' . strlen($str) . ' Written: ' . (int) $ret,
                 Exception::WRITE_ERROR
             );
         }
diff --git a/src/LineBreaksHelper.php b/src/LineBreaksHelper.php
new file mode 100644
index 0000000..a6e18d6
--- /dev/null
+++ b/src/LineBreaksHelper.php
@@ -0,0 +1,99 @@
+<?php
+
+namespace Keboola\Csv;
+
+class LineBreaksHelper
+{
+    const REGEXP_DELIMITER = '~';
+
+    /**
+     * Detect line-breaks style in CSV file
+     * @param string $sample
+     * @param string $enclosure
+     * @param string $escapedBy
+     * @return string
+     */
+    public static function detectLineBreaks($sample, $enclosure, $escapedBy)
+    {
+        $cleared = self::clearCsvValues($sample, $enclosure, $escapedBy);
+
+        $possibleLineBreaks = [
+            "\r\n", // win
+            "\r", // mac
+            "\n", // unix
+        ];
+
+        $lineBreaksPositions = [];
+        foreach ($possibleLineBreaks as $lineBreak) {
+            $position = strpos($cleared, $lineBreak);
+            if ($position === false) {
+                continue;
+            }
+            $lineBreaksPositions[$lineBreak] = $position;
+        }
+
+
+        asort($lineBreaksPositions);
+        reset($lineBreaksPositions);
+
+        return empty($lineBreaksPositions) ? "\n" : key($lineBreaksPositions);
+    }
+
+    /**
+     * Clear enclosured values in CSV eg. "abc" to "",
+     * because these values can contain line breaks eg, "abc\n\r\n\r\r\r\r",
+     * and this makes it difficult to detect line breaks style in CSV,
+     * if are another line breaks present in first line.
+     * @internal Should be used only in detectLineBreaks, public for easier testing.
+     * @param string $sample
+     * @param string $enclosure
+     * @param string $escapedBy eg. empty string or \
+     * @return string
+     */
+    public static function clearCsvValues($sample, $enclosure, $escapedBy)
+    {
+        // Usually an enclosure character is escaped by doubling it, however, the escapeBy can be used
+        $doubleEnclosure = $enclosure . $enclosure;
+        $escapedEnclosure = empty($escapedBy) ? $doubleEnclosure : $escapedBy . $enclosure;
+        $escapedEscape = empty($escapedBy) ? null : $escapedBy . $escapedBy;
+
+        /*
+         * Regexp examples:
+         * enclosure: |"|, escapedBy: none, regexp: ~"(?>(?>"")|[^"])*"~
+         * enclosure: |"|, escapedBy: |\|,  regexp: ~"(?>(?>\\"|\\\\)|[^"])*"~
+        */
+        // @formatter:off
+        $regexp =
+            // regexp start
+            self::REGEXP_DELIMITER .
+                // enclosure start
+                preg_quote($enclosure, self::REGEXP_DELIMITER) .
+                    /*
+                     * Once-only group => if there is a match, do not try other alternatives
+                     * See: https://www.php.net/manual/en/regexp.reference.onlyonce.php
+                     * Without once-only group will be |"abc\"| false positive,
+                     * because |\| is matched by group and |"| at the end of regexp.
+                     */
+                    // repeated once-only group start
+                    '(?>' .
+                            // once-only group start
+                            '(?>' .
+                                // escaped enclosure
+                                preg_quote($escapedEnclosure, self::REGEXP_DELIMITER) .
+                                // OR escaped escape char
+                                ($escapedEscape ? '|' . preg_quote($escapedEscape, self::REGEXP_DELIMITER) : '') .
+                            // group end
+                            ')' .
+                            // OR not enclosure
+                            '|[^' . preg_quote($enclosure, self::REGEXP_DELIMITER) . ']' .
+                    // group end
+                    ')*' .
+                // enclosure end
+                preg_quote($enclosure, self::REGEXP_DELIMITER) .
+            // regexp end
+            self::REGEXP_DELIMITER;
+        // @formatter:on
+
+        return preg_replace($regexp, $doubleEnclosure, $sample);
+    }
+}
diff --git a/tests/CsvReadTest.php b/tests/CsvReadTest.php
index c6bff66..dec42c5 100644
--- a/tests/CsvReadTest.php
+++ b/tests/CsvReadTest.php
@@ -137,6 +137,24 @@ public function testParseEscapedBy()
         self::assertEquals($expected, iterator_to_array($csvFile));
     }
 
+    public function testParseMacLineEndsInField()
+    {
+        $csvFile = new CsvReader(__DIR__ . '/data/test-input.lineBreaks.csv', ",", '"', '\\');
+
+        $expected = [
+            [
+                'test',
+                "some text\rwith\r\\r line breaks\rinside\rbut\rrows\rare\rusing \\n \\\"line\\\" break\r",
+            ],
+            [
+                'name', 'data'
+            ]
+        ];
+
+        self::assertEquals($expected, iterator_to_array($csvFile));
+    }
+
+
     public function testEmptyHeader()
     {
         $csvFile = new CsvReader(__DIR__ . '/data/test-input.empty.csv', ',', '"');
@@ -364,14 +382,6 @@ public function invalidSkipLinesProvider()
         ];
     }
 
-    public function testInvalidNewLines()
-    {
-        self::expectException(Exception::class);
-        self::expectExceptionMessage('Invalid line break. Please use unix \n or win \r\n line breaks.');
-        new CsvReader(__DIR__ . DIRECTORY_SEPARATOR . 'data/binary');
-    }
-
-
     public function testValidWithoutRewind()
     {
         $fileName = __DIR__ . '/data/simple.csv';
@@ -479,4 +489,54 @@ public function testInvalidFile()
         self::expectExceptionMessage('Invalid file: array');
         new CsvReader(['bad']);
     }
+
+    /**
+     * @dataProvider getPerformanceTestInputs
+     * @param string $fileContent
+     * @param int $expectedRows
+     * @param float $maxDuration
+     */
+    public function testPerformance($fileContent, $expectedRows, $maxDuration)
+    {
+        self::markTestSkipped(
+            'Run this test only manually. Because the duration is very different in local CI environment.'
+        );
+
+        try {
+            $fileName = sys_get_temp_dir() . DIRECTORY_SEPARATOR . uniqid('perf-test');
+            file_put_contents($fileName, $fileContent);
+            $startTime = microtime(true);
+            $reader = new CsvReader($fileName);
+            $rows = 0;
+            foreach ($reader as $line){
+                $rows++;
+            }
+            $duration = microtime(true) - $startTime;
+            self::assertSame($expectedRows, $rows);
+            self::assertLessThanOrEqual($maxDuration, $duration);
+        } finally {
+            @unlink($fileName);
+        }
+    }
+
+    public function getPerformanceTestInputs()
+    {
+        yield '1M-simple-rows' => [
+            str_repeat("abc,def,\"xyz\"\n", 1000000),
+            1000000,
+            8.0
+        ];
+
+        yield '1M-empty-lines-n' => [
+            str_repeat("\n", 1000000),
+            1000000,
+            8.0
+        ];
+
+        yield '1M-no-separators' => [
+            str_repeat(md5('abc') . "\n", 1000000),
+            1000000,
+            8.0
+        ];
+    }
 }
diff --git a/tests/CsvWriteTest.php b/tests/CsvWriteTest.php
index a3323a4..24f77f8 100644
--- a/tests/CsvWriteTest.php
+++ b/tests/CsvWriteTest.php
@@ -6,6 +6,8 @@
 use Keboola\Csv\CsvWriter;
 use Keboola\Csv\Exception;
 use PHPUnit\Framework\TestCase;
+use PHPUnit_Framework_Constraint_Or;
+use PHPUnit_Framework_Constraint_StringContains;
 
 class CsvWriteTest extends TestCase
 {
@@ -87,9 +89,19 @@ public function testWriteInvalidObject()
         ];
 
         $csvFile->writeRow($rows[0]);
-        self::expectException(Exception::class);
-        self::expectExceptionMessage("Cannot write data into column: stdClass::");
-        $csvFile->writeRow($rows[1]);
+
+        try {
+            $csvFile->writeRow($rows[1]);
+            self::fail('Expected exception was not thrown.');
+        } catch (Exception $e) {
+            // Exception message differs between PHP versions.
+            $or = new PHPUnit_Framework_Constraint_Or();
+            $or->setConstraints([
+                new PHPUnit_Framework_Constraint_StringContains("Cannot write data into column: stdClass::"),
+                new PHPUnit_Framework_Constraint_StringContains("Cannot write data into column: (object) array(\n)")
+            ]);
+            self::assertThat($e->getMessage(), $or);
+        }
     }
 
     public function testWriteValidObject()
@@ -182,9 +194,24 @@ public function testInvalidPointer()
         $pointer = fopen($fileName, 'r');
         $csvFile = new CsvWriter($pointer);
         $rows = [['col1', 'col2']];
-        self::expectException(Exception::class);
-        self::expectExceptionMessage('Cannot write to CSV file  Return: 0 To write: 14 Written: 0');
-        $csvFile->writeRow($rows[0]);
+
+        try {
+            $csvFile->writeRow($rows[0]);
+            self::fail('Expected exception was not thrown.');
+        } catch (Exception $e) {
+            // Exception message differs between PHP versions.
+            $or = new PHPUnit_Framework_Constraint_Or();
+            $or->setConstraints([
+                new PHPUnit_Framework_Constraint_StringContains(
+                    'Cannot write to CSV file  Return: 0 To write: 14 Written: 0'
+                ),
+                new PHPUnit_Framework_Constraint_StringContains(
+                    'Cannot write to CSV file Error: fwrite(): ' .
+                    'write of 14 bytes failed with errno=9 Bad file descriptor Return: false To write: 14 Written: 0'
+                )
+            ]);
+            self::assertThat($e->getMessage(), $or);
+        }
     }
 
     public function testInvalidPointer2()
diff --git a/tests/LineBreaksHelperTest.php b/tests/LineBreaksHelperTest.php
new file mode 100644
index 0000000..5f22caa
--- /dev/null
+++ b/tests/LineBreaksHelperTest.php
@@ -0,0 +1,140 @@
+<?php
+
+namespace Keboola\Csv\Tests;
+
+use Keboola\Csv\LineBreaksHelper;
+use PHPUnit\Framework\TestCase;
+
+class LineBreaksHelperTest extends TestCase
+{
+    /**
+     * @dataProvider getDataSet
+     * @param string $enclosure
+     * @param string $escapedBy
+     * @param string $input
+     * @param string $expectedOutput
+     * @param string $expectedLineBreak
+     */
+    public function testLineBreaksDetection($enclosure, $escapedBy, $input, $expectedOutput, $expectedLineBreak)
+    {
+        // Test clear CSV values
+        $output = LineBreaksHelper::clearCsvValues($input, $enclosure, $escapedBy);
+        self::assertSame($expectedOutput, $output);
+
+        // The same result must be returned when used multiple times
+        $output2 = LineBreaksHelper::clearCsvValues($output, $enclosure, $escapedBy);
+        self::assertSame($expectedOutput, $output2);
+
+        // Test line breaks detection
+        self::assertSame(json_encode($expectedLineBreak), json_encode(LineBreaksHelper::detectLineBreaks($input, $enclosure, $escapedBy)));
+    }
+
+    public function getDataSet()
+    {
+        $lineEnds = [
+          'n' => "\n",
+          'r' => "\r",
+          "r-n" => "\r\n",
+        ];
+
+        yield "empty" => [
+            '"',
+            '',
+            '',
+            '',
+            "\n"
+        ];
+
+        yield "empty-escaped-by" => [
+            '"',
+            '\\',
+            '',
+            '',
+            "\n"
+        ];
+
+        foreach ($lineEnds as $prefix => $lineEnd) {
+            yield "$prefix-simple" => [
+                '"',
+                '',
+                implode($lineEnd, [
+                    'col1,col2',
+                    'line without enclosure,second column',
+                    '"enclosure "" in column","hello \"',
+                    '"line with enclosure","second column"',
+                    '"column with enclosure "", and comma inside text","second column enclosure in text """',
+                ]),
+                implode($lineEnd, [
+                    'col1,col2',
+                    'line without enclosure,second column',
+                    '"",""',
+                    '"",""',
+                    '"",""',
+                ]),
+                $lineEnd
+            ];
+
+            yield "$prefix-simple-escaped-by" => [
+                '"',
+                '\\',
+                implode($lineEnd, [
+                    'col1,col2',
+                    'line without enclosure,second column',
+                    '"enclosure \" in column","hello \\\\"',
+                    '"line with enclosure","second column"',
+                    '"column with enclosure \", and comma inside text","second column enclosure in text \""'
+                ]),
+                implode($lineEnd, [
+                    'col1,col2',
+                    'line without enclosure,second column',
+                    '"",""',
+                    '"",""',
+                    '"",""',
+                ]),
+                $lineEnd
+            ];
+
+            yield "$prefix-multiline-n" => [
+                '"',
+                '',
+                implode($lineEnd, [
+                    "\"xyz\",\"\n\n\nabc\n\n\n\"\"\n\n\nxyz\n\n\n\"",
+                    '"abc","def"',
+                ]),
+                implode($lineEnd, [
+                    '"",""',
+                    '"",""',
+                ]),
+                $lineEnd
+            ];
+
+            yield "$prefix-multiline-r" => [
+                '"',
+                '',
+                implode($lineEnd, [
+                    "\"xyz\",\"\r\r\rabc\r\r\r\"\"\r\r\rxyz\r\r\r\"",
+                    '"abc","def"',
+                ]),
+                implode($lineEnd, [
+                    '"",""',
+                    '"",""',
+                ]),
+                $lineEnd
+            ];
+
+            yield "$prefix-multiline-r-n" => [
+                '"',
+                '',
+                implode($lineEnd, [
+                    "\"xyz\",\"\r\n\r\n\r\nabc\r\n\r\n\r\n\"\"\r\n\r\n\r\nxyz\r\n\r\n\r\n\"",
+                    '"abc","def"',
+                ]),
+                implode($lineEnd, [
+                    '"",""',
+                    '"",""',
+                ]),
+                $lineEnd
+            ];
+        }
+    }
+}
diff --git a/tests/data/binary b/tests/data/binary
deleted file mode 100644
index 421f1a7..0000000
Binary files a/tests/data/binary and /dev/null differ
diff --git a/tests/data/test-input.lineBreaks.csv b/tests/data/test-input.lineBreaks.csv
new file mode 100644
index 0000000..ed4ce9d
--- /dev/null
+++ b/tests/data/test-input.lineBreaks.csv
@@ -0,0 +1,2 @@
+"test","some text
with
\r line breaks
inside
but
rows
are
using \n \"line\" break
"
+"name","data"