diff --git a/.gitignore b/.gitignore
index 7611d841f..664d419cf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 composer.lock
 tests/.phpunit.result.cache
 vendor
+/.php-cs-fixer.cache
diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
new file mode 100644
index 000000000..c5635b0d4
--- /dev/null
+++ b/.php-cs-fixer.dist.php
@@ -0,0 +1,38 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in(__DIR__.'/hamcrest')
+    ->in(__DIR__.'/generator')
+    ->in(__DIR__.'/tests')
+    ->notPath('Matchers.php')
+    ->notPath('Hamcrest.php')
+    ->name('*.php')
+;
+
+return (new PhpCsFixer\Config())
+    ->setRules([
+        // Use PSR-12 as base but disable the cosmetic rules
+        '@PSR12' => true,
+        
+        // namespace should come directly after the opening tag
+        'blank_line_after_opening_tag' => false,
+        'linebreak_after_opening_tag' => true,
+        'blank_lines_before_namespace' => ['min_line_breaks' => 1, 'max_line_breaks' => 1],
+
+        // add semicolons to the last lines of chained calls
+        'multiline_whitespace_before_semicolons' => ['strategy' => 'new_line_for_chained_calls'],
+        'method_chaining_indentation' => true,
+
+        // parentheses on new expressions when there are no arguments
+        'new_with_parentheses' => ['named_class' => true, 'anonymous_class' => true],
+
+        // use consistent naming for boolean, bool, integer, int, etc
+        'phpdoc_scalar' => true,
+
+        // allow a new line after the class opening
+        'no_blank_lines_after_class_opening' => false,
+
+    ])
+    ->setFinder($finder)
+    ->setRiskyAllowed(false)
+;
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 5df55df9f..badb4e872 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -12,11 +12,18 @@ Feel free to ask any questions and share your experiences in the [Issue tracking
 1. Create your feature addition or a bug fix branch based on __`master`__ branch in your repository's fork.
 2. Make necessary changes, but __don't mix__ code reformatting with code changes on topic.
 3. Add tests for those changes (please look into `tests/` folder for some examples). This is important so we don't break it in a future version unintentionally.
-4. Check your code using "Coding Standard" (see below).
+4. Fix your code style by using the "Coding Standard" (see below).
 5. Commit your code.
 6. Squash your commits by topic to preserve a clean and readable log.
 7. Create Pull Request.
 
+## Coding Standard
+
+To keep a consice coding standard in the repository, run: 
+```bash
+vendor/bin/php-cs-fixer fix
+```
+
 ## Running the Tests
 
 ### Installation/Configuration
diff --git a/composer.json b/composer.json
index ddffd1939..a86827ba0 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,8 @@
 
 	"require-dev": {
 		"phpunit/php-file-iterator": "^1.4 || ^2.0 || ^3.0",
-		"phpunit/phpunit": "^4.8.36 || ^5.7 || ^6.5 || ^7.0 || ^8.0 || ^9.0"
+		"phpunit/phpunit": "^4.8.36 || ^5.7 || ^6.5 || ^7.0 || ^8.0 || ^9.0",
+		"friendsofphp/php-cs-fixer": "^3.75"
 	},
 
 	"replace": {
diff --git a/generator/FactoryCall.php b/generator/FactoryCall.php
index 83965b2ae..31986262f 100644
--- a/generator/FactoryCall.php
+++ b/generator/FactoryCall.php
@@ -11,7 +11,7 @@ class FactoryCall
      *
      * @var string
      */
-    const INDENT = '    ';
+    public const INDENT = '    ';
 
     /**
      * @var FactoryMethod
diff --git a/generator/FactoryFile.php b/generator/FactoryFile.php
index dd6109b1f..55a3fbe71 100644
--- a/generator/FactoryFile.php
+++ b/generator/FactoryFile.php
@@ -11,7 +11,7 @@ abstract class FactoryFile
      *
      * @var string
      */
-    const INDENT = '    ';
+    public const INDENT = '    ';
 
     private $indent;
 
diff --git a/generator/GlobalFunctionFile.php b/generator/GlobalFunctionFile.php
index ec8b1b392..ce86824cb 100644
--- a/generator/GlobalFunctionFile.php
+++ b/generator/GlobalFunctionFile.php
@@ -34,8 +34,8 @@ public function build()
     public function generateFactoryCall(FactoryCall $call)
     {
         $code = "if (!function_exists('{$call->getName()}')) {\n";
-        $code.= parent::generateFactoryCall($call);
-        $code.= "}\n";
+        $code .= parent::generateFactoryCall($call);
+        $code .= "}\n";
 
         return $code;
     }
diff --git a/hamcrest/Hamcrest/Arrays/IsArray.php b/hamcrest/Hamcrest/Arrays/IsArray.php
index 9ea569703..0827332f7 100644
--- a/hamcrest/Hamcrest/Arrays/IsArray.php
+++ b/hamcrest/Hamcrest/Arrays/IsArray.php
@@ -55,13 +55,13 @@ protected function describeMismatchSafely($actual, Description $mismatchDescript
             return;
         } elseif (array_keys($actual) != array_keys($this->_elementMatchers)) {
             $mismatchDescription->appendText('array keys were ')
-                                                    ->appendValueList(
-                                                        $this->descriptionStart(),
-                                                        $this->descriptionSeparator(),
-                                                        $this->descriptionEnd(),
-                                                        array_keys($actual)
-                                                    )
-                                                    ;
+                ->appendValueList(
+                    $this->descriptionStart(),
+                    $this->descriptionSeparator(),
+                    $this->descriptionEnd(),
+                    array_keys($actual)
+                )
+            ;
 
             return;
         }
@@ -70,7 +70,8 @@ protected function describeMismatchSafely($actual, Description $mismatchDescript
         foreach ($this->_elementMatchers as $k => $matcher) {
             if (!$matcher->matches($actual[$k])) {
                 $mismatchDescription->appendText('element ')->appendValue($k)
-                    ->appendText(' was ')->appendValue($actual[$k]);
+                    ->appendText(' was ')->appendValue($actual[$k])
+                ;
 
                 return;
             }
diff --git a/hamcrest/Hamcrest/Arrays/IsArrayContaining.php b/hamcrest/Hamcrest/Arrays/IsArrayContaining.php
index 0e4a1eda9..8b6895782 100644
--- a/hamcrest/Hamcrest/Arrays/IsArrayContaining.php
+++ b/hamcrest/Hamcrest/Arrays/IsArrayContaining.php
@@ -43,8 +43,8 @@ protected function describeMismatchSafely($array, Description $mismatchDescripti
     public function describeTo(Description $description)
     {
         $description
-                 ->appendText('an array containing ')
-                 ->appendDescriptionOf($this->_elementMatcher)
+            ->appendText('an array containing ')
+            ->appendDescriptionOf($this->_elementMatcher)
         ;
     }
 
diff --git a/hamcrest/Hamcrest/Arrays/IsArrayContainingInAnyOrder.php b/hamcrest/Hamcrest/Arrays/IsArrayContainingInAnyOrder.php
index 9009026b8..8ac0c27bb 100644
--- a/hamcrest/Hamcrest/Arrays/IsArrayContainingInAnyOrder.php
+++ b/hamcrest/Hamcrest/Arrays/IsArrayContainingInAnyOrder.php
@@ -41,8 +41,8 @@ protected function matchesSafelyWithDiagnosticDescription($array, Description $m
     public function describeTo(Description $description)
     {
         $description->appendList('[', ', ', ']', $this->_elementMatchers)
-                                ->appendText(' in any order')
-                                ;
+            ->appendText(' in any order')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Arrays/IsArrayContainingKey.php b/hamcrest/Hamcrest/Arrays/IsArrayContainingKey.php
index 523477e7b..23ab6e6a0 100644
--- a/hamcrest/Hamcrest/Arrays/IsArrayContainingKey.php
+++ b/hamcrest/Hamcrest/Arrays/IsArrayContainingKey.php
@@ -39,8 +39,8 @@ protected function describeMismatchSafely($array, Description $mismatchDescripti
     {
         //Not using appendValueList() so that keys can be shown
         $mismatchDescription->appendText('array was ')
-                                                ->appendText('[')
-                                                ;
+            ->appendText('[')
+        ;
         $loop = false;
         foreach ($array as $key => $value) {
             if ($loop) {
@@ -55,9 +55,9 @@ protected function describeMismatchSafely($array, Description $mismatchDescripti
     public function describeTo(Description $description)
     {
         $description
-                 ->appendText('array with key ')
-                 ->appendDescriptionOf($this->_keyMatcher)
-                 ;
+            ->appendText('array with key ')
+            ->appendDescriptionOf($this->_keyMatcher)
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Arrays/IsArrayContainingKeyValuePair.php b/hamcrest/Hamcrest/Arrays/IsArrayContainingKeyValuePair.php
index 9ac3eba80..e6e0af2d4 100644
--- a/hamcrest/Hamcrest/Arrays/IsArrayContainingKeyValuePair.php
+++ b/hamcrest/Hamcrest/Arrays/IsArrayContainingKeyValuePair.php
@@ -42,8 +42,8 @@ protected function describeMismatchSafely($array, Description $mismatchDescripti
     {
         //Not using appendValueList() so that keys can be shown
         $mismatchDescription->appendText('array was ')
-                                                ->appendText('[')
-                                                ;
+            ->appendText('[')
+        ;
         $loop = false;
         foreach ($array as $key => $value) {
             if ($loop) {
@@ -58,11 +58,11 @@ protected function describeMismatchSafely($array, Description $mismatchDescripti
     public function describeTo(Description $description)
     {
         $description->appendText('array containing [')
-                                ->appendDescriptionOf($this->_keyMatcher)
-                                ->appendText(' => ')
-                                ->appendDescriptionOf($this->_valueMatcher)
-                                ->appendText(']')
-                                ;
+            ->appendDescriptionOf($this->_keyMatcher)
+            ->appendText(' => ')
+            ->appendDescriptionOf($this->_valueMatcher)
+            ->appendText(']')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Arrays/MatchingOnce.php b/hamcrest/Hamcrest/Arrays/MatchingOnce.php
index 324c7e089..c515e9113 100644
--- a/hamcrest/Hamcrest/Arrays/MatchingOnce.php
+++ b/hamcrest/Hamcrest/Arrays/MatchingOnce.php
@@ -31,9 +31,9 @@ public function isFinished($items)
         }
 
         $this->_mismatchDescription
-                 ->appendText('No item matches: ')->appendList('', ', ', '', $this->_elementMatchers)
-                 ->appendText(' in ')->appendValueList('[', ', ', ']', $items)
-                 ;
+            ->appendText('No item matches: ')->appendList('', ', ', '', $this->_elementMatchers)
+            ->appendText(' in ')->appendValueList('[', ', ', ']', $items)
+        ;
 
         return false;
     }
@@ -53,7 +53,7 @@ private function _isNotSurplus($item)
 
     private function _isMatched($item)
     {
-            /** @var $matcher \Hamcrest\Matcher */
+        /** @var $matcher \Hamcrest\Matcher */
         foreach ($this->_elementMatchers as $i => $matcher) {
             if ($matcher->matches($item)) {
                 unset($this->_elementMatchers[$i]);
diff --git a/hamcrest/Hamcrest/Collection/IsEmptyTraversable.php b/hamcrest/Hamcrest/Collection/IsEmptyTraversable.php
index 8ab58ea5a..90a172bbf 100644
--- a/hamcrest/Hamcrest/Collection/IsEmptyTraversable.php
+++ b/hamcrest/Hamcrest/Collection/IsEmptyTraversable.php
@@ -49,7 +49,7 @@ public function describeTo(Description $description)
     public static function emptyTraversable()
     {
         if (!self::$_INSTANCE) {
-            self::$_INSTANCE = new self;
+            self::$_INSTANCE = new self();
         }
 
         return self::$_INSTANCE;
diff --git a/hamcrest/Hamcrest/Core/DescribedAs.php b/hamcrest/Hamcrest/Core/DescribedAs.php
index 5b2583fa7..b22c31c72 100644
--- a/hamcrest/Hamcrest/Core/DescribedAs.php
+++ b/hamcrest/Hamcrest/Core/DescribedAs.php
@@ -18,7 +18,7 @@ class DescribedAs extends BaseMatcher
     private $_matcher;
     private $_values;
 
-    const ARG_PATTERN = '/%([0-9]+)/';
+    public const ARG_PATTERN = '/%([0-9]+)/';
 
     public function __construct($descriptionTemplate, Matcher $matcher, array $values)
     {
diff --git a/hamcrest/Hamcrest/Core/IsCollectionContaining.php b/hamcrest/Hamcrest/Core/IsCollectionContaining.php
index 5e60426d1..71eab0b0d 100644
--- a/hamcrest/Hamcrest/Core/IsCollectionContaining.php
+++ b/hamcrest/Hamcrest/Core/IsCollectionContaining.php
@@ -43,9 +43,9 @@ protected function describeMismatchSafely($items, Description $mismatchDescripti
     public function describeTo(Description $description)
     {
         $description
-                ->appendText('a collection containing ')
-                ->appendDescriptionOf($this->_elementMatcher)
-                ;
+            ->appendText('a collection containing ')
+            ->appendDescriptionOf($this->_elementMatcher)
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Core/IsInstanceOf.php b/hamcrest/Hamcrest/Core/IsInstanceOf.php
index 7a5c92a6b..ba419fbaa 100644
--- a/hamcrest/Hamcrest/Core/IsInstanceOf.php
+++ b/hamcrest/Hamcrest/Core/IsInstanceOf.php
@@ -37,7 +37,8 @@ protected function matchesWithDiagnosticDescription($item, Description $mismatch
 
         if (!($item instanceof $this->_theClass)) {
             $mismatchDescription->appendText('[' . get_class($item) . '] ')
-                                                    ->appendValue($item);
+                ->appendValue($item)
+            ;
 
             return false;
         }
@@ -48,8 +49,8 @@ protected function matchesWithDiagnosticDescription($item, Description $mismatch
     public function describeTo(Description $description)
     {
         $description->appendText('an instance of ')
-                                ->appendText($this->_theClass)
-                                ;
+            ->appendText($this->_theClass)
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Core/IsSame.php b/hamcrest/Hamcrest/Core/IsSame.php
index 810787050..94432eddd 100644
--- a/hamcrest/Hamcrest/Core/IsSame.php
+++ b/hamcrest/Hamcrest/Core/IsSame.php
@@ -29,9 +29,9 @@ public function matches($object)
     public function describeTo(Description $description)
     {
         $description->appendText('sameInstance(')
-                                ->appendValue($this->_object)
-                                ->appendText(')')
-                                ;
+            ->appendValue($this->_object)
+            ->appendText(')')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Core/IsTypeOf.php b/hamcrest/Hamcrest/Core/IsTypeOf.php
index d24f0f94c..7092c0643 100644
--- a/hamcrest/Hamcrest/Core/IsTypeOf.php
+++ b/hamcrest/Hamcrest/Core/IsTypeOf.php
@@ -42,10 +42,10 @@ public function describeMismatch($item, Description $description)
             $description->appendText('was null');
         } else {
             $description->appendText('was ')
-                                    ->appendText(self::getTypeDescription(strtolower(gettype($item))))
-                                    ->appendText(' ')
-                                    ->appendValue($item)
-                                    ;
+                ->appendText(self::getTypeDescription(strtolower(gettype($item))))
+                ->appendText(' ')
+                ->appendValue($item)
+            ;
         }
     }
 
diff --git a/hamcrest/Hamcrest/FeatureMatcher.php b/hamcrest/Hamcrest/FeatureMatcher.php
index 59f6cc734..1a12bdb80 100644
--- a/hamcrest/Hamcrest/FeatureMatcher.php
+++ b/hamcrest/Hamcrest/FeatureMatcher.php
@@ -50,7 +50,8 @@ public function matchesSafelyWithDiagnosticDescription($actual, Description $mis
 
         if (!$this->_subMatcher->matches($featureValue)) {
             $mismatchDescription->appendText($this->_featureName)
-                                                    ->appendText(' was ')->appendValue($featureValue);
+                ->appendText(' was ')->appendValue($featureValue)
+            ;
 
             return false;
         }
@@ -61,7 +62,7 @@ public function matchesSafelyWithDiagnosticDescription($actual, Description $mis
     final public function describeTo(Description $description)
     {
         $description->appendText($this->_featureDescription)->appendText(' ')
-                                ->appendDescriptionOf($this->_subMatcher)
-                             ;
+            ->appendDescriptionOf($this->_subMatcher)
+        ;
     }
 }
diff --git a/hamcrest/Hamcrest/Matcher.php b/hamcrest/Hamcrest/Matcher.php
index e5dcf0939..10b6d8f38 100644
--- a/hamcrest/Hamcrest/Matcher.php
+++ b/hamcrest/Hamcrest/Matcher.php
@@ -28,23 +28,23 @@ interface Matcher extends SelfDescribing
      *
      * @param mixed $item the object against which the matcher is evaluated.
      *
-     * @return boolean <code>true</code> if <var>$item</var> matches,
+     * @return bool <code>true</code> if <var>$item</var> matches,
      *   otherwise <code>false</code>.
      *
      * @see Hamcrest\BaseMatcher
      */
     public function matches($item);
 
-        /**
-         * Generate a description of why the matcher has not accepted the item.
-         * The description will be part of a larger description of why a matching
-         * failed, so it should be concise.
-         * This method assumes that <code>matches($item)</code> is false, but
-         * will not check this.
-         *
-         * @param mixed $item The item that the Matcher has rejected.
-         * @param Description $description
-         * @return
-         */
+    /**
+     * Generate a description of why the matcher has not accepted the item.
+     * The description will be part of a larger description of why a matching
+     * failed, so it should be concise.
+     * This method assumes that <code>matches($item)</code> is false, but
+     * will not check this.
+     *
+     * @param mixed $item The item that the Matcher has rejected.
+     * @param Description $description
+     * @return
+     */
     public function describeMismatch($item, Description $description);
 }
diff --git a/hamcrest/Hamcrest/MatcherAssert.php b/hamcrest/Hamcrest/MatcherAssert.php
index d546dbee6..dff1971fb 100644
--- a/hamcrest/Hamcrest/MatcherAssert.php
+++ b/hamcrest/Hamcrest/MatcherAssert.php
@@ -107,8 +107,9 @@ private static function doAssert($identifier, $actual, Matcher $matcher)
                 $description->appendText($identifier . PHP_EOL);
             }
             $description->appendText('Expected: ')
-                                    ->appendDescriptionOf($matcher)
-                                    ->appendText(PHP_EOL . '     but: ');
+                ->appendDescriptionOf($matcher)
+                ->appendText(PHP_EOL . '     but: ')
+            ;
 
             $matcher->describeMismatch($actual, $description);
 
diff --git a/hamcrest/Hamcrest/Number/IsCloseTo.php b/hamcrest/Hamcrest/Number/IsCloseTo.php
index 15453e526..8efea877e 100644
--- a/hamcrest/Hamcrest/Number/IsCloseTo.php
+++ b/hamcrest/Hamcrest/Number/IsCloseTo.php
@@ -33,18 +33,18 @@ protected function matchesSafely($item)
     protected function describeMismatchSafely($item, Description $mismatchDescription)
     {
         $mismatchDescription->appendValue($item)
-                                                ->appendText(' differed by ')
-                                                ->appendValue($this->_actualDelta($item))
-                                                ;
+            ->appendText(' differed by ')
+            ->appendValue($this->_actualDelta($item))
+        ;
     }
 
     public function describeTo(Description $description)
     {
         $description->appendText('a numeric value within ')
-                                ->appendValue($this->_delta)
-                                ->appendText(' of ')
-                                ->appendValue($this->_value)
-                                ;
+            ->appendValue($this->_delta)
+            ->appendText(' of ')
+            ->appendValue($this->_value)
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Number/OrderingComparison.php b/hamcrest/Hamcrest/Number/OrderingComparison.php
index 369d0cfa5..6248c570a 100644
--- a/hamcrest/Hamcrest/Number/OrderingComparison.php
+++ b/hamcrest/Hamcrest/Number/OrderingComparison.php
@@ -37,18 +37,18 @@ protected function describeMismatchSafely($item, Description $mismatchDescriptio
             ->appendValue($item)->appendText(' was ')
             ->appendText($this->_comparison($this->_compare($this->_value, $item)))
             ->appendText(' ')->appendValue($this->_value)
-            ;
+        ;
     }
 
     public function describeTo(Description $description)
     {
         $description->appendText('a value ')
             ->appendText($this->_comparison($this->_minCompare))
-            ;
+        ;
         if ($this->_minCompare != $this->_maxCompare) {
             $description->appendText(' or ')
                 ->appendText($this->_comparison($this->_maxCompare))
-                ;
+            ;
         }
         $description->appendText(' ')->appendValue($this->_value);
     }
diff --git a/hamcrest/Hamcrest/Text/IsEqualIgnoringCase.php b/hamcrest/Hamcrest/Text/IsEqualIgnoringCase.php
index 3836a8c37..939623aa1 100644
--- a/hamcrest/Hamcrest/Text/IsEqualIgnoringCase.php
+++ b/hamcrest/Hamcrest/Text/IsEqualIgnoringCase.php
@@ -35,9 +35,9 @@ protected function describeMismatchSafely($item, Description $mismatchDescriptio
     public function describeTo(Description $description)
     {
         $description->appendText('equalToIgnoringCase(')
-                                ->appendValue($this->_string)
-                                ->appendText(')')
-                                ;
+            ->appendValue($this->_string)
+            ->appendText(')')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Text/IsEqualIgnoringWhiteSpace.php b/hamcrest/Hamcrest/Text/IsEqualIgnoringWhiteSpace.php
index 853692b03..5951b711f 100644
--- a/hamcrest/Hamcrest/Text/IsEqualIgnoringWhiteSpace.php
+++ b/hamcrest/Hamcrest/Text/IsEqualIgnoringWhiteSpace.php
@@ -37,9 +37,9 @@ protected function describeMismatchSafely($item, Description $mismatchDescriptio
     public function describeTo(Description $description)
     {
         $description->appendText('equalToIgnoringWhiteSpace(')
-                                ->appendValue($this->_string)
-                                ->appendText(')')
-                                ;
+            ->appendValue($this->_string)
+            ->appendText(')')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Text/StringContainsInOrder.php b/hamcrest/Hamcrest/Text/StringContainsInOrder.php
index e75de65d2..03e9935d2 100644
--- a/hamcrest/Hamcrest/Text/StringContainsInOrder.php
+++ b/hamcrest/Hamcrest/Text/StringContainsInOrder.php
@@ -43,9 +43,9 @@ protected function describeMismatchSafely($item, Description $mismatchDescriptio
     public function describeTo(Description $description)
     {
         $description->appendText('a string containing ')
-                                ->appendValueList('', ', ', '', $this->_substrings)
-                                ->appendText(' in order')
-                                ;
+            ->appendValueList('', ', ', '', $this->_substrings)
+            ->appendText(' in order')
+        ;
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Text/SubstringMatcher.php b/hamcrest/Hamcrest/Text/SubstringMatcher.php
index e560ad627..96a31dcd0 100644
--- a/hamcrest/Hamcrest/Text/SubstringMatcher.php
+++ b/hamcrest/Hamcrest/Text/SubstringMatcher.php
@@ -33,10 +33,10 @@ protected function describeMismatchSafely($item, Description $mismatchDescriptio
     public function describeTo(Description $description)
     {
         $description->appendText('a string ')
-                                ->appendText($this->relationship())
-                                ->appendText(' ')
-                                ->appendValue($this->_substring)
-                                ;
+            ->appendText($this->relationship())
+            ->appendText(' ')
+            ->appendValue($this->_substring)
+        ;
     }
 
     abstract protected function evalSubstringOf($string);
diff --git a/hamcrest/Hamcrest/Type/IsArray.php b/hamcrest/Hamcrest/Type/IsArray.php
index 9179102ff..7ffc69694 100644
--- a/hamcrest/Hamcrest/Type/IsArray.php
+++ b/hamcrest/Hamcrest/Type/IsArray.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function arrayValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsBoolean.php b/hamcrest/Hamcrest/Type/IsBoolean.php
index 35b617cf4..f8fa1daf6 100644
--- a/hamcrest/Hamcrest/Type/IsBoolean.php
+++ b/hamcrest/Hamcrest/Type/IsBoolean.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function booleanValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsCallable.php b/hamcrest/Hamcrest/Type/IsCallable.php
index f2bcd35ba..507774901 100644
--- a/hamcrest/Hamcrest/Type/IsCallable.php
+++ b/hamcrest/Hamcrest/Type/IsCallable.php
@@ -32,6 +32,6 @@ public function matches($item)
      */
     public static function callableValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsDouble.php b/hamcrest/Hamcrest/Type/IsDouble.php
index 3ddd8e852..8b057f485 100644
--- a/hamcrest/Hamcrest/Type/IsDouble.php
+++ b/hamcrest/Hamcrest/Type/IsDouble.php
@@ -29,6 +29,6 @@ public function __construct()
      */
     public static function doubleValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsInteger.php b/hamcrest/Hamcrest/Type/IsInteger.php
index 47c86bd68..df3926d40 100644
--- a/hamcrest/Hamcrest/Type/IsInteger.php
+++ b/hamcrest/Hamcrest/Type/IsInteger.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function integerValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsNumeric.php b/hamcrest/Hamcrest/Type/IsNumeric.php
index bc7440547..c9673af1e 100644
--- a/hamcrest/Hamcrest/Type/IsNumeric.php
+++ b/hamcrest/Hamcrest/Type/IsNumeric.php
@@ -31,7 +31,7 @@ public function matches($item)
      * This check is necessary because PHP 7 doesn't recognize hexadecimal string as numeric anymore.
      *
      * @param mixed $item
-     * @return boolean
+     * @return bool
      */
     private function isHexadecimal($item)
     {
@@ -49,6 +49,6 @@ private function isHexadecimal($item)
      */
     public static function numericValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsObject.php b/hamcrest/Hamcrest/Type/IsObject.php
index 65918fcf3..31f3d8e3c 100644
--- a/hamcrest/Hamcrest/Type/IsObject.php
+++ b/hamcrest/Hamcrest/Type/IsObject.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function objectValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsResource.php b/hamcrest/Hamcrest/Type/IsResource.php
index 426cf77c9..3bffc1ae6 100644
--- a/hamcrest/Hamcrest/Type/IsResource.php
+++ b/hamcrest/Hamcrest/Type/IsResource.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function resourceValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsScalar.php b/hamcrest/Hamcrest/Type/IsScalar.php
index 3f3b427fa..8b207c2bf 100644
--- a/hamcrest/Hamcrest/Type/IsScalar.php
+++ b/hamcrest/Hamcrest/Type/IsScalar.php
@@ -29,6 +29,6 @@ public function matches($item)
      */
     public static function scalarValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/Type/IsString.php b/hamcrest/Hamcrest/Type/IsString.php
index d96d7db38..d852a4a3e 100644
--- a/hamcrest/Hamcrest/Type/IsString.php
+++ b/hamcrest/Hamcrest/Type/IsString.php
@@ -27,6 +27,6 @@ public function __construct()
      */
     public static function stringValue()
     {
-        return new self;
+        return new self();
     }
 }
diff --git a/hamcrest/Hamcrest/TypeSafeMatcher.php b/hamcrest/Hamcrest/TypeSafeMatcher.php
index 56e299a9a..dc3532038 100644
--- a/hamcrest/Hamcrest/TypeSafeMatcher.php
+++ b/hamcrest/Hamcrest/TypeSafeMatcher.php
@@ -14,13 +14,13 @@ abstract class TypeSafeMatcher extends BaseMatcher
 {
 
     /* Types that PHP can compare against */
-    const TYPE_ANY = 0;
-    const TYPE_STRING = 1;
-    const TYPE_NUMERIC = 2;
-    const TYPE_ARRAY = 3;
-    const TYPE_OBJECT = 4;
-    const TYPE_RESOURCE = 5;
-    const TYPE_BOOLEAN = 6;
+    public const TYPE_ANY = 0;
+    public const TYPE_STRING = 1;
+    public const TYPE_NUMERIC = 2;
+    public const TYPE_ARRAY = 3;
+    public const TYPE_OBJECT = 4;
+    public const TYPE_RESOURCE = 5;
+    public const TYPE_BOOLEAN = 6;
 
     /**
      * The type that is required for a safe comparison
diff --git a/hamcrest/Hamcrest/Util.php b/hamcrest/Hamcrest/Util.php
index 169b03663..7c0b5afeb 100644
--- a/hamcrest/Hamcrest/Util.php
+++ b/hamcrest/Hamcrest/Util.php
@@ -27,8 +27,7 @@ public static function wrapValueWithIsEqual($item)
     {
         return ($item instanceof Matcher)
             ? $item
-            : Core\IsEqual::equalTo($item)
-            ;
+            : Core\IsEqual::equalTo($item);
     }
 
     /**
diff --git a/hamcrest/Hamcrest/Xml/HasXPath.php b/hamcrest/Hamcrest/Xml/HasXPath.php
index bedf9694a..b1c9eeea2 100644
--- a/hamcrest/Hamcrest/Xml/HasXPath.php
+++ b/hamcrest/Hamcrest/Xml/HasXPath.php
@@ -131,7 +131,8 @@ protected function matchesContent(\DOMNodeList $nodes, Description $mismatchDesc
                 $content[] = $node->textContent;
             }
             $mismatchDescription->appendText('XPath returned ')
-                                                    ->appendValue($content);
+                ->appendValue($content)
+            ;
         }
 
         return false;
@@ -152,7 +153,8 @@ protected function matchesExpression($result, Description $mismatchDescription)
                 return true;
             }
             $mismatchDescription->appendText('XPath expression result was ')
-                                                    ->appendValue($result);
+                ->appendValue($result)
+            ;
         } else {
             if ($this->_matcher->matches($result)) {
                 return true;
@@ -167,8 +169,9 @@ protected function matchesExpression($result, Description $mismatchDescription)
     public function describeTo(Description $description)
     {
         $description->appendText('XML or HTML document with XPath "')
-                                ->appendText($this->_xpath)
-                                ->appendText('"');
+            ->appendText($this->_xpath)
+            ->appendText('"')
+        ;
         if ($this->_matcher !== null) {
             $description->appendText(' ');
             $this->_matcher->describeTo($description);
diff --git a/tests/Hamcrest/AbstractMatcherTest.php b/tests/Hamcrest/AbstractMatcherTest.php
index 8a1fb2a95..64b8dd8ef 100644
--- a/tests/Hamcrest/AbstractMatcherTest.php
+++ b/tests/Hamcrest/AbstractMatcherTest.php
@@ -3,14 +3,15 @@
 
 use PHPUnit\Framework\TestCase;
 
-class UnknownType {
+class UnknownType
+{
 }
 
 abstract class AbstractMatcherTest extends TestCase
 {
 
-    const ARGUMENT_IGNORED = "ignored";
-    const ANY_NON_NULL_ARGUMENT = "notnull";
+    public const ARGUMENT_IGNORED = "ignored";
+    public const ANY_NON_NULL_ARGUMENT = "notnull";
 
     abstract protected function createMatcher();
 
diff --git a/tests/Hamcrest/Array/IsArrayContainingKeyTest.php b/tests/Hamcrest/Array/IsArrayContainingKeyTest.php
index 31770d8dd..1155f6971 100644
--- a/tests/Hamcrest/Array/IsArrayContainingKeyTest.php
+++ b/tests/Hamcrest/Array/IsArrayContainingKeyTest.php
@@ -13,14 +13,14 @@ protected function createMatcher()
 
     public function testMatchesSingleElementArrayContainingKey()
     {
-        $array = array('a'=>1);
+        $array = array('a' => 1);
 
         $this->assertMatches(hasKey('a'), $array, 'Matches single key');
     }
 
     public function testMatchesArrayContainingKey()
     {
-        $array = array('a'=>1, 'b'=>2, 'c'=>3);
+        $array = array('a' => 1, 'b' => 2, 'c' => 3);
 
         $this->assertMatches(hasKey('a'), $array, 'Matches a');
         $this->assertMatches(hasKey('c'), $array, 'Matches c');
@@ -28,14 +28,14 @@ public function testMatchesArrayContainingKey()
 
     public function testMatchesArrayContainingKeyWithIntegerKeys()
     {
-        $array = array(1=>'A', 2=>'B');
+        $array = array(1 => 'A', 2 => 'B');
 
         assertThat($array, hasKey(1));
     }
 
     public function testMatchesArrayContainingKeyWithNumberKeys()
     {
-        $array = array(1=>'A', 2=>'B');
+        $array = array(1 => 'A', 2 => 'B');
 
         assertThat($array, hasKey(1));
 
@@ -55,7 +55,7 @@ public function testDoesNotMatchEmptyArray()
 
     public function testDoesNotMatchArrayMissingKey()
     {
-        $array = array('a'=>1, 'b'=>2, 'c'=>3);
+        $array = array('a' => 1, 'b' => 2, 'c' => 3);
 
         $this->assertMismatchDescription('array was ["a" => <1>, "b" => <2>, "c" => <3>]', hasKey('d'), $array);
     }
diff --git a/tests/Hamcrest/Array/IsArrayContainingKeyValuePairTest.php b/tests/Hamcrest/Array/IsArrayContainingKeyValuePairTest.php
index a415f9f7a..c88d250d9 100644
--- a/tests/Hamcrest/Array/IsArrayContainingKeyValuePairTest.php
+++ b/tests/Hamcrest/Array/IsArrayContainingKeyValuePairTest.php
@@ -13,7 +13,7 @@ protected function createMatcher()
 
     public function testMatchesArrayContainingMatchingKeyAndValue()
     {
-        $array = array('a'=>1, 'b'=>2);
+        $array = array('a' => 1, 'b' => 2);
 
         $this->assertMatches(hasKeyValuePair(equalTo('a'), equalTo(1)), $array, 'matcherA');
         $this->assertMatches(hasKeyValuePair(equalTo('b'), equalTo(2)), $array, 'matcherB');
diff --git a/tests/Hamcrest/Array/IsArrayTest.php b/tests/Hamcrest/Array/IsArrayTest.php
index e4db53e79..cba7e8b75 100644
--- a/tests/Hamcrest/Array/IsArrayTest.php
+++ b/tests/Hamcrest/Array/IsArrayTest.php
@@ -72,8 +72,8 @@ public function testHasAReadableMismatchDescriptionWhenKeysDontMatch()
     public function testSupportsMatchesAssociativeArrays()
     {
         $this->assertMatches(
-            anArray(array('x'=>equalTo('a'), 'y'=>equalTo('b'), 'z'=>equalTo('c'))),
-            array('x'=>'a', 'y'=>'b', 'z'=>'c'),
+            anArray(array('x' => equalTo('a'), 'y' => equalTo('b'), 'z' => equalTo('c'))),
+            array('x' => 'a', 'y' => 'b', 'z' => 'c'),
             'should match associative array with matching elements'
         );
     }
@@ -81,8 +81,8 @@ public function testSupportsMatchesAssociativeArrays()
     public function testDoesNotMatchAnAssociativeArrayWhenKeysDoNotMatch()
     {
         $this->assertDoesNotMatch(
-            anArray(array('x'=>equalTo('a'), 'y'=>equalTo('b'))),
-            array('x'=>'b', 'z'=>'c'),
+            anArray(array('x' => equalTo('a'), 'y' => equalTo('b'))),
+            array('x' => 'b', 'z' => 'c'),
             'should not match array with different keys'
         );
     }
diff --git a/tests/Hamcrest/StringDescriptionTest.php b/tests/Hamcrest/StringDescriptionTest.php
index b42b9b469..f788e178e 100644
--- a/tests/Hamcrest/StringDescriptionTest.php
+++ b/tests/Hamcrest/StringDescriptionTest.php
@@ -130,7 +130,7 @@ public function testSelfDescribingObjectsCanBeAppended()
         $this->_description
             ->appendDescriptionOf(new \Hamcrest\SampleSelfDescriber('foo'))
             ->appendDescriptionOf(new \Hamcrest\SampleSelfDescriber('bar'))
-            ;
+        ;
         $this->assertEquals('foobar', (string) $this->_description);
     }
 
diff --git a/tests/Hamcrest/Text/StringContainsIgnoringCaseTest.php b/tests/Hamcrest/Text/StringContainsIgnoringCaseTest.php
index 8b4463a9e..082214fa5 100644
--- a/tests/Hamcrest/Text/StringContainsIgnoringCaseTest.php
+++ b/tests/Hamcrest/Text/StringContainsIgnoringCaseTest.php
@@ -4,7 +4,7 @@
 class StringContainsIgnoringCaseTest extends \Hamcrest\AbstractMatcherTest
 {
 
-    const EXCERPT = 'ExcErPt';
+    public const EXCERPT = 'ExcErPt';
 
     private $_stringContains;
 
diff --git a/tests/Hamcrest/Text/StringContainsTest.php b/tests/Hamcrest/Text/StringContainsTest.php
index 814c1ca1b..baa19bfcf 100644
--- a/tests/Hamcrest/Text/StringContainsTest.php
+++ b/tests/Hamcrest/Text/StringContainsTest.php
@@ -4,7 +4,7 @@
 class StringContainsTest extends \Hamcrest\AbstractMatcherTest
 {
 
-    const EXCERPT = 'EXCERPT';
+    public const EXCERPT = 'EXCERPT';
 
     private $_stringContains;
 
diff --git a/tests/Hamcrest/Text/StringEndsWithTest.php b/tests/Hamcrest/Text/StringEndsWithTest.php
index 46177f464..aab91f0e7 100644
--- a/tests/Hamcrest/Text/StringEndsWithTest.php
+++ b/tests/Hamcrest/Text/StringEndsWithTest.php
@@ -4,7 +4,7 @@
 class StringEndsWithTest extends \Hamcrest\AbstractMatcherTest
 {
 
-    const EXCERPT = 'EXCERPT';
+    public const EXCERPT = 'EXCERPT';
 
     private $_stringEndsWith;
 
diff --git a/tests/Hamcrest/Text/StringStartsWithTest.php b/tests/Hamcrest/Text/StringStartsWithTest.php
index f0eb14b7e..a1a9255f6 100644
--- a/tests/Hamcrest/Text/StringStartsWithTest.php
+++ b/tests/Hamcrest/Text/StringStartsWithTest.php
@@ -4,7 +4,7 @@
 class StringStartsWithTest extends \Hamcrest\AbstractMatcherTest
 {
 
-    const EXCERPT = 'EXCERPT';
+    public const EXCERPT = 'EXCERPT';
 
     private $_stringStartsWith;
 
diff --git a/tests/Hamcrest/Type/IsDoubleTest.php b/tests/Hamcrest/Type/IsDoubleTest.php
index 85c2a963c..41c03bd3b 100644
--- a/tests/Hamcrest/Type/IsDoubleTest.php
+++ b/tests/Hamcrest/Type/IsDoubleTest.php
@@ -12,7 +12,7 @@ protected function createMatcher()
     public function testEvaluatesToTrueIfArgumentMatchesType()
     {
         assertThat((float) 5.2, floatValue());
-        assertThat((double) 5.3, doubleValue());
+        assertThat((float) 5.3, doubleValue());
     }
 
     public function testEvaluatesToFalseIfArgumentDoesntMatchType()
diff --git a/tests/Hamcrest/Type/IsObjectTest.php b/tests/Hamcrest/Type/IsObjectTest.php
index a3b617c20..33e054eec 100644
--- a/tests/Hamcrest/Type/IsObjectTest.php
+++ b/tests/Hamcrest/Type/IsObjectTest.php
@@ -11,7 +11,7 @@ protected function createMatcher()
 
     public function testEvaluatesToTrueIfArgumentMatchesType()
     {
-        assertThat(new \stdClass, objectValue());
+        assertThat(new \stdClass(), objectValue());
     }
 
     public function testEvaluatesToFalseIfArgumentDoesntMatchType()