diff --git a/.travis.yml b/.travis.yml
index f2a60e2c..bf48be80 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,6 +12,7 @@ matrix:
       env: DEPENDENCIES='low'
     - php: 7.1
     - php: 7.2
+    - php: 7.3
 
 before_install:
   - composer self-update
@@ -23,3 +24,4 @@ install:
 
 script:
   - ./bin/phpunit
+  - ./bin/php-cs-fixer fix -v --dry-run
diff --git a/src/Matcher/Pattern/Expander/After.php b/src/Matcher/Pattern/Expander/After.php
index 8369f68a..2cddeb9d 100644
--- a/src/Matcher/Pattern/Expander/After.php
+++ b/src/Matcher/Pattern/Expander/After.php
@@ -17,7 +17,7 @@ final class After implements PatternExpander
 
 
     public function __construct($boundary)
-    {      
+    {
         if (false === \is_string($boundary)) {
             $this->error = \sprintf('After expander require "string", got "%s".', new StringConverter($boundary));
             return false;
diff --git a/src/Matcher/Pattern/Expander/Before.php b/src/Matcher/Pattern/Expander/Before.php
index 5803d576..a0a10332 100644
--- a/src/Matcher/Pattern/Expander/Before.php
+++ b/src/Matcher/Pattern/Expander/Before.php
@@ -35,7 +35,7 @@ public static function is(string $name) : bool
     }
 
     public function match($value) : bool
-    {        
+    {
         if (!\is_string($value)) {
             $this->error = \sprintf('Before expander require "string", got "%s".', new StringConverter($value));
             return false;
diff --git a/src/Matcher/Pattern/Expander/NotContains.php b/src/Matcher/Pattern/Expander/NotContains.php
index ccdb36b8..d9f12b05 100644
--- a/src/Matcher/Pattern/Expander/NotContains.php
+++ b/src/Matcher/Pattern/Expander/NotContains.php
@@ -40,7 +40,7 @@ public function match($value) : bool
             : \mb_strpos($value, $this->string);
 
         if ($contains !== false) {
-            $this->error = \sprintf("String \"%s\" contains \"%s\".", $value, $this->string);
+            $this->error = \sprintf('String "%s" contains "%s".', $value, $this->string);
 
             return false;
         }
diff --git a/src/Parser.php b/src/Parser.php
index f3199b6e..c43e3e09 100644
--- a/src/Parser.php
+++ b/src/Parser.php
@@ -46,7 +46,7 @@ public function parse(string $pattern) : Pattern\TypePattern
 
     public function getAST(string $pattern) : AST\Pattern
     {
-        if($pattern === '') {
+        if ($pattern === '') {
             return new AST\Pattern(new AST\Type(''));
         }
 
diff --git a/tests/Matcher/Pattern/Expander/NotContainsTest.php b/tests/Matcher/Pattern/Expander/NotContainsTest.php
index 1dfdfef4..5bfe42b0 100644
--- a/tests/Matcher/Pattern/Expander/NotContainsTest.php
+++ b/tests/Matcher/Pattern/Expander/NotContainsTest.php
@@ -4,7 +4,6 @@
 
 namespace Coduo\PHPMatcher\Tests\Matcher\Pattern\Expander;
 
-use Coduo\PHPMatcher\Matcher\Pattern\Expander\Contains;
 use Coduo\PHPMatcher\Matcher\Pattern\Expander\NotContains;
 use PHPUnit\Framework\TestCase;
 
@@ -61,7 +60,7 @@ public function test_error_when_matching_fail($string, $value, $errorMessage)
     public static function invalidCasesProvider()
     {
         return [
-            ['ipsum', 'lorem ipsum', "String \"lorem ipsum\" contains \"ipsum\"."],
+            ['ipsum', 'lorem ipsum', 'String "lorem ipsum" contains "ipsum".'],
             ['lorem', new \DateTime(), 'Not contains expander require "string", got "\\DateTime".'],
         ];
     }
diff --git a/tests/MatcherTest.php b/tests/MatcherTest.php
index 449a1015..7998e0d0 100644
--- a/tests/MatcherTest.php
+++ b/tests/MatcherTest.php
@@ -360,7 +360,7 @@ public static function expanderExamples()
             ['lorem ipsum', '@string@.isUrl()', false],
             ['2014-08-19', '@string@.isDateTime()', true],
             ['3014-08-19', '@string@.before("today")', false],
-            ['1014-08-19', '@string@.before("+ 1day")', true], 
+            ['1014-08-19', '@string@.before("+ 1day")', true],
             ['3014-08-19', '@string@.after("today")', true],
             ['1014-08-19', '@string@.after("+ 1day")', false],
             [100, '@integer@.lowerThan(101).greaterThan(10)', true],