diff --git a/.travis.yml b/.travis.yml
index 73fb498..1a8cda2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,16 +8,11 @@ cache:
 
 matrix:
   include:
-    - php: 7.2
+    - php: 7.4
       env:
         - CS_CHECK=true
         - TEST_COVERAGE=true
         - PHPSTAN=true
-    - php: 7.3
-      env:
-        - CS_CHECK=false
-        - TEST_COVERAGE=false
-        - PHPSTAN=false
     - php: nightly
       env:
         - CS_CHECK=false
diff --git a/composer.json b/composer.json
index dca242b..394a214 100644
--- a/composer.json
+++ b/composer.json
@@ -20,14 +20,14 @@
     "zendframework/zend-validator": "^2.10"
   },
   "require-dev": {
-    "infection/infection": "^0.13.4",
+    "infection/infection": "^0.15.1",
     "php-coveralls/php-coveralls": "~2.1",
-    "phpstan/phpstan": "~0.11",
-    "phpstan/phpstan-strict-rules": "~0.11",
-    "phpstan/phpstan-phpunit": "~0.11",
-    "phpunit/phpunit": "^8.0",
+    "phpstan/phpstan": "~0.12.9",
+    "phpstan/phpstan-strict-rules": "~0.12.2",
+    "phpstan/phpstan-phpunit": "~0.12.6",
+    "phpunit/phpunit": "^8.5.2",
     "roave/security-advisories": "dev-master",
-    "zendframework/zend-coding-standard": "~1.0"
+    "squizlabs/php_codesniffer": "^3.5.3"
   },
   "autoload": {
     "psr-4": {
diff --git a/composer.lock b/composer.lock
index 939b6b4..ce67879 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "dc0e7e350d794ae9b3b9b080b632e0ac",
+    "content-hash": "4ecd79f1933b00e7482f4b4504e3dc47",
     "packages": [
         {
             "name": "container-interop/container-interop",
@@ -259,62 +259,6 @@
         }
     ],
     "packages-dev": [
-        {
-            "name": "composer/ca-bundle",
-            "version": "1.2.6",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/composer/ca-bundle.git",
-                "reference": "47fe531de31fca4a1b997f87308e7d7804348f7e"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/composer/ca-bundle/zipball/47fe531de31fca4a1b997f87308e7d7804348f7e",
-                "reference": "47fe531de31fca4a1b997f87308e7d7804348f7e",
-                "shasum": ""
-            },
-            "require": {
-                "ext-openssl": "*",
-                "ext-pcre": "*",
-                "php": "^5.3.2 || ^7.0 || ^8.0"
-            },
-            "require-dev": {
-                "phpunit/phpunit": "^4.8.35 || ^5.7 || 6.5 - 8",
-                "psr/log": "^1.0",
-                "symfony/process": "^2.5 || ^3.0 || ^4.0 || ^5.0"
-            },
-            "type": "library",
-            "extra": {
-                "branch-alias": {
-                    "dev-master": "1.x-dev"
-                }
-            },
-            "autoload": {
-                "psr-4": {
-                    "Composer\\CaBundle\\": "src"
-                }
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "MIT"
-            ],
-            "authors": [
-                {
-                    "name": "Jordi Boggiano",
-                    "email": "j.boggiano@seld.be",
-                    "homepage": "http://seld.be"
-                }
-            ],
-            "description": "Lets you find a path to the system CA bundle, and includes a fallback to the Mozilla CA bundle.",
-            "keywords": [
-                "cabundle",
-                "cacert",
-                "certificate",
-                "ssl",
-                "tls"
-            ],
-            "time": "2020-01-13T10:02:55+00:00"
-        },
         {
             "name": "composer/xdebug-handler",
             "version": "1.4.0",
@@ -606,44 +550,46 @@
         },
         {
             "name": "infection/infection",
-            "version": "0.13.6",
+            "version": "0.15.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/infection/infection.git",
-                "reference": "09b4d371d203f7f22dcf1741a3f6c657404fb61e"
+                "reference": "96c6a3fc5714f96345ecfa27ade6f361adde5ddc"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/infection/infection/zipball/09b4d371d203f7f22dcf1741a3f6c657404fb61e",
-                "reference": "09b4d371d203f7f22dcf1741a3f6c657404fb61e",
+                "url": "https://api.github.com/repos/infection/infection/zipball/96c6a3fc5714f96345ecfa27ade6f361adde5ddc",
+                "reference": "96c6a3fc5714f96345ecfa27ade6f361adde5ddc",
                 "shasum": ""
             },
             "require": {
-                "composer/xdebug-handler": "^1.3",
+                "composer/xdebug-handler": "^1.3.3",
                 "ext-dom": "*",
                 "ext-json": "*",
                 "ext-libxml": "*",
                 "justinrainbow/json-schema": "^5.2",
-                "nikic/php-parser": "^4.2.1",
+                "nikic/php-parser": "^4.2.2",
                 "ocramius/package-versions": "^1.2",
-                "padraic/phar-updater": "^1.0.4",
-                "php": "^7.1.3",
+                "php": "^7.2.9",
                 "pimple/pimple": "^3.2",
-                "sebastian/diff": "^1.4 || ^2.0 || ^3.0",
-                "symfony/console": "^3.4 || ^4.0",
-                "symfony/filesystem": "^3.4 || ^4.0",
-                "symfony/finder": "^3.4 || ^4.0",
-                "symfony/process": "^3.4 || ^4.0",
-                "symfony/yaml": "^3.4 || ^4.0",
-                "webmozart/assert": "^1.3"
+                "sebastian/diff": "^3.0.2",
+                "seld/jsonlint": "^1.7",
+                "symfony/console": "^3.4.29 || ^4.0 || ^5.0",
+                "symfony/filesystem": "^3.4.29 || ^4.0 || ^5.0",
+                "symfony/finder": "^3.4.29 || ^4.0 || ^5.0",
+                "symfony/process": "^3.4.29 || ^4.0 || ^5.0",
+                "symfony/yaml": "^3.4.29 || ^4.0 || ^5.0",
+                "thecodingmachine/safe": "^0.1.16",
+                "webmozart/assert": "^1.3",
+                "webmozart/path-util": "^2.3"
             },
             "conflict": {
-                "symfony/console": "=3.4.16 || =4.1.5",
-                "symfony/process": "3.4.2"
+                "symfony/console": "=4.1.5"
             },
             "require-dev": {
-                "helmich/phpunit-json-assert": "^2.1 || ^3.0",
-                "phpunit/phpunit": "^7.5"
+                "helmich/phpunit-json-assert": "^3.0",
+                "phpunit/phpunit": "^8.2.5 <8.4",
+                "symfony/phpunit-bridge": "^4.3.4 || ^5.0"
             },
             "bin": [
                 "bin/infection"
@@ -681,6 +627,11 @@
                     "name": "Alexey Kopytko",
                     "email": "alexey@kopytko.com",
                     "homepage": "https://www.alexeykopytko.com"
+                },
+                {
+                    "name": "Andreas Möller",
+                    "email": "am@localheinz.com",
+                    "homepage": "https://localheinz.com"
                 }
             ],
             "description": "Infection is a Mutation Testing framework for PHP. The mutation adequacy score can be used to measure the effectiveness of a test set in terms of its ability to detect faults.",
@@ -692,7 +643,7 @@
                 "testing",
                 "unit testing"
             ],
-            "time": "2019-08-29T19:22:44+00:00"
+            "time": "2020-02-06T12:53:30+00:00"
         },
         {
             "name": "justinrainbow/json-schema",
@@ -911,127 +862,6 @@
             "description": "Composer plugin that provides efficient querying for installed package versions (no runtime IO)",
             "time": "2019-07-17T15:49:50+00:00"
         },
-        {
-            "name": "padraic/humbug_get_contents",
-            "version": "1.1.2",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/humbug/file_get_contents.git",
-                "reference": "dcb086060c9dd6b2f51d8f7a895500307110b7a7"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/humbug/file_get_contents/zipball/dcb086060c9dd6b2f51d8f7a895500307110b7a7",
-                "reference": "dcb086060c9dd6b2f51d8f7a895500307110b7a7",
-                "shasum": ""
-            },
-            "require": {
-                "composer/ca-bundle": "^1.0",
-                "ext-openssl": "*",
-                "php": "^5.3 || ^7.0 || ^7.1 || ^7.2"
-            },
-            "require-dev": {
-                "bamarni/composer-bin-plugin": "^1.1",
-                "mikey179/vfsstream": "^1.6",
-                "phpunit/phpunit": "^4.8 || ^5.7 || ^6.5"
-            },
-            "type": "library",
-            "extra": {
-                "bamarni-bin": {
-                    "bin-links": false
-                },
-                "branch-alias": {
-                    "dev-master": "2.0-dev"
-                }
-            },
-            "autoload": {
-                "psr-4": {
-                    "Humbug\\": "src/"
-                },
-                "files": [
-                    "src/function.php",
-                    "src/functions.php"
-                ]
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "BSD-3-Clause"
-            ],
-            "authors": [
-                {
-                    "name": "Pádraic Brady",
-                    "email": "padraic.brady@gmail.com",
-                    "homepage": "http://blog.astrumfutura.com"
-                },
-                {
-                    "name": "Théo Fidry",
-                    "email": "theo.fidry@gmail.com"
-                }
-            ],
-            "description": "Secure wrapper for accessing HTTPS resources with file_get_contents for PHP 5.3+",
-            "homepage": "https://github.com/padraic/file_get_contents",
-            "keywords": [
-                "download",
-                "file_get_contents",
-                "http",
-                "https",
-                "ssl",
-                "tls"
-            ],
-            "time": "2018-02-12T18:47:17+00:00"
-        },
-        {
-            "name": "padraic/phar-updater",
-            "version": "v1.0.6",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/humbug/phar-updater.git",
-                "reference": "d01d3b8f26e541ac9b9eeba1e18d005d852f7ff1"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/humbug/phar-updater/zipball/d01d3b8f26e541ac9b9eeba1e18d005d852f7ff1",
-                "reference": "d01d3b8f26e541ac9b9eeba1e18d005d852f7ff1",
-                "shasum": ""
-            },
-            "require": {
-                "padraic/humbug_get_contents": "^1.0",
-                "php": ">=5.3.3"
-            },
-            "require-dev": {
-                "phpunit/phpunit": "~4.0"
-            },
-            "type": "library",
-            "extra": {
-                "branch-alias": {
-                    "dev-master": "1.0-dev"
-                }
-            },
-            "autoload": {
-                "psr-4": {
-                    "Humbug\\SelfUpdate\\": "src/"
-                }
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "BSD-3-Clause"
-            ],
-            "authors": [
-                {
-                    "name": "Pádraic Brady",
-                    "email": "padraic.brady@gmail.com",
-                    "homepage": "http://blog.astrumfutura.com"
-                }
-            ],
-            "description": "A thing to make PHAR self-updating easy and secure.",
-            "keywords": [
-                "humbug",
-                "phar",
-                "self-update",
-                "update"
-            ],
-            "time": "2018-03-30T12:52:15+00:00"
-        },
         {
             "name": "phar-io/manifest",
             "version": "1.0.3",
@@ -2905,66 +2735,88 @@
             "homepage": "https://github.com/sebastianbergmann/version",
             "time": "2016-10-03T07:35:21+00:00"
         },
+        {
+            "name": "seld/jsonlint",
+            "version": "1.7.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/Seldaek/jsonlint.git",
+                "reference": "e2e5d290e4d2a4f0eb449f510071392e00e10d19"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/Seldaek/jsonlint/zipball/e2e5d290e4d2a4f0eb449f510071392e00e10d19",
+                "reference": "e2e5d290e4d2a4f0eb449f510071392e00e10d19",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.3 || ^7.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.8.35 || ^5.7 || ^6.0"
+            },
+            "bin": [
+                "bin/jsonlint"
+            ],
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Seld\\JsonLint\\": "src/Seld/JsonLint/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jordi Boggiano",
+                    "email": "j.boggiano@seld.be",
+                    "homepage": "http://seld.be"
+                }
+            ],
+            "description": "JSON Linter",
+            "keywords": [
+                "json",
+                "linter",
+                "parser",
+                "validator"
+            ],
+            "time": "2019-10-24T14:27:39+00:00"
+        },
         {
             "name": "squizlabs/php_codesniffer",
-            "version": "2.9.2",
+            "version": "3.5.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/squizlabs/PHP_CodeSniffer.git",
-                "reference": "2acf168de78487db620ab4bc524135a13cfe6745"
+                "reference": "dceec07328401de6211037abbb18bda423677e26"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/squizlabs/PHP_CodeSniffer/zipball/2acf168de78487db620ab4bc524135a13cfe6745",
-                "reference": "2acf168de78487db620ab4bc524135a13cfe6745",
+                "url": "https://api.github.com/repos/squizlabs/PHP_CodeSniffer/zipball/dceec07328401de6211037abbb18bda423677e26",
+                "reference": "dceec07328401de6211037abbb18bda423677e26",
                 "shasum": ""
             },
             "require": {
                 "ext-simplexml": "*",
                 "ext-tokenizer": "*",
                 "ext-xmlwriter": "*",
-                "php": ">=5.1.2"
+                "php": ">=5.4.0"
             },
             "require-dev": {
-                "phpunit/phpunit": "~4.0"
+                "phpunit/phpunit": "^4.0 || ^5.0 || ^6.0 || ^7.0"
             },
             "bin": [
-                "scripts/phpcs",
-                "scripts/phpcbf"
+                "bin/phpcs",
+                "bin/phpcbf"
             ],
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "2.x-dev"
+                    "dev-master": "3.x-dev"
                 }
             },
-            "autoload": {
-                "classmap": [
-                    "CodeSniffer.php",
-                    "CodeSniffer/CLI.php",
-                    "CodeSniffer/Exception.php",
-                    "CodeSniffer/File.php",
-                    "CodeSniffer/Fixer.php",
-                    "CodeSniffer/Report.php",
-                    "CodeSniffer/Reporting.php",
-                    "CodeSniffer/Sniff.php",
-                    "CodeSniffer/Tokens.php",
-                    "CodeSniffer/Reports/",
-                    "CodeSniffer/Tokenizers/",
-                    "CodeSniffer/DocGenerators/",
-                    "CodeSniffer/Standards/AbstractPatternSniff.php",
-                    "CodeSniffer/Standards/AbstractScopeSniff.php",
-                    "CodeSniffer/Standards/AbstractVariableSniff.php",
-                    "CodeSniffer/Standards/IncorrectPatternException.php",
-                    "CodeSniffer/Standards/Generic/Sniffs/",
-                    "CodeSniffer/Standards/MySource/Sniffs/",
-                    "CodeSniffer/Standards/PEAR/Sniffs/",
-                    "CodeSniffer/Standards/PSR1/Sniffs/",
-                    "CodeSniffer/Standards/PSR2/Sniffs/",
-                    "CodeSniffer/Standards/Squiz/Sniffs/",
-                    "CodeSniffer/Standards/Zend/Sniffs/"
-                ]
-            },
             "notification-url": "https://packagist.org/downloads/",
             "license": [
                 "BSD-3-Clause"
@@ -2976,12 +2828,12 @@
                 }
             ],
             "description": "PHP_CodeSniffer tokenizes PHP, JavaScript and CSS files and detects violations of a defined set of coding standards.",
-            "homepage": "http://www.squizlabs.com/php-codesniffer",
+            "homepage": "https://github.com/squizlabs/PHP_CodeSniffer",
             "keywords": [
                 "phpcs",
                 "standards"
             ],
-            "time": "2018-11-07T22:31:41+00:00"
+            "time": "2020-01-30T22:20:29+00:00"
         },
         {
             "name": "symfony/config",
@@ -3049,41 +2901,41 @@
         },
         {
             "name": "symfony/console",
-            "version": "v4.4.4",
+            "version": "v5.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/console.git",
-                "reference": "f512001679f37e6a042b51897ed24a2f05eba656"
+                "reference": "91c294166c38d8c0858a86fad76d8c14dc1144c8"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/console/zipball/f512001679f37e6a042b51897ed24a2f05eba656",
-                "reference": "f512001679f37e6a042b51897ed24a2f05eba656",
+                "url": "https://api.github.com/repos/symfony/console/zipball/91c294166c38d8c0858a86fad76d8c14dc1144c8",
+                "reference": "91c294166c38d8c0858a86fad76d8c14dc1144c8",
                 "shasum": ""
             },
             "require": {
-                "php": "^7.1.3",
+                "php": "^7.2.5",
                 "symfony/polyfill-mbstring": "~1.0",
                 "symfony/polyfill-php73": "^1.8",
                 "symfony/service-contracts": "^1.1|^2"
             },
             "conflict": {
-                "symfony/dependency-injection": "<3.4",
-                "symfony/event-dispatcher": "<4.3|>=5",
+                "symfony/dependency-injection": "<4.4",
+                "symfony/event-dispatcher": "<4.4",
                 "symfony/lock": "<4.4",
-                "symfony/process": "<3.3"
+                "symfony/process": "<4.4"
             },
             "provide": {
                 "psr/log-implementation": "1.0"
             },
             "require-dev": {
                 "psr/log": "~1.0",
-                "symfony/config": "^3.4|^4.0|^5.0",
-                "symfony/dependency-injection": "^3.4|^4.0|^5.0",
-                "symfony/event-dispatcher": "^4.3",
+                "symfony/config": "^4.4|^5.0",
+                "symfony/dependency-injection": "^4.4|^5.0",
+                "symfony/event-dispatcher": "^4.4|^5.0",
                 "symfony/lock": "^4.4|^5.0",
-                "symfony/process": "^3.4|^4.0|^5.0",
-                "symfony/var-dumper": "^4.3|^5.0"
+                "symfony/process": "^4.4|^5.0",
+                "symfony/var-dumper": "^4.4|^5.0"
             },
             "suggest": {
                 "psr/log": "For using the console logger",
@@ -3094,7 +2946,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "4.4-dev"
+                    "dev-master": "5.0-dev"
                 }
             },
             "autoload": {
@@ -3121,30 +2973,30 @@
             ],
             "description": "Symfony Console Component",
             "homepage": "https://symfony.com",
-            "time": "2020-01-25T12:44:29+00:00"
+            "time": "2020-01-25T15:56:29+00:00"
         },
         {
             "name": "symfony/filesystem",
-            "version": "v4.4.4",
+            "version": "v5.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/filesystem.git",
-                "reference": "266c9540b475f26122b61ef8b23dd9198f5d1cfd"
+                "reference": "3afadc0f57cd74f86379d073e694b0f2cda2a88c"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/filesystem/zipball/266c9540b475f26122b61ef8b23dd9198f5d1cfd",
-                "reference": "266c9540b475f26122b61ef8b23dd9198f5d1cfd",
+                "url": "https://api.github.com/repos/symfony/filesystem/zipball/3afadc0f57cd74f86379d073e694b0f2cda2a88c",
+                "reference": "3afadc0f57cd74f86379d073e694b0f2cda2a88c",
                 "shasum": ""
             },
             "require": {
-                "php": "^7.1.3",
+                "php": "^7.2.5",
                 "symfony/polyfill-ctype": "~1.8"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "4.4-dev"
+                    "dev-master": "5.0-dev"
                 }
             },
             "autoload": {
@@ -3171,29 +3023,29 @@
             ],
             "description": "Symfony Filesystem Component",
             "homepage": "https://symfony.com",
-            "time": "2020-01-21T08:20:44+00:00"
+            "time": "2020-01-21T08:40:24+00:00"
         },
         {
             "name": "symfony/finder",
-            "version": "v4.4.4",
+            "version": "v5.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/finder.git",
-                "reference": "3a50be43515590faf812fbd7708200aabc327ec3"
+                "reference": "4176e7cb846fe08f32518b7e0ed8462e2db8d9bb"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/finder/zipball/3a50be43515590faf812fbd7708200aabc327ec3",
-                "reference": "3a50be43515590faf812fbd7708200aabc327ec3",
+                "url": "https://api.github.com/repos/symfony/finder/zipball/4176e7cb846fe08f32518b7e0ed8462e2db8d9bb",
+                "reference": "4176e7cb846fe08f32518b7e0ed8462e2db8d9bb",
                 "shasum": ""
             },
             "require": {
-                "php": "^7.1.3"
+                "php": "^7.2.5"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "4.4-dev"
+                    "dev-master": "5.0-dev"
                 }
             },
             "autoload": {
@@ -3220,7 +3072,7 @@
             ],
             "description": "Symfony Finder Component",
             "homepage": "https://symfony.com",
-            "time": "2020-01-04T13:00:46+00:00"
+            "time": "2020-01-04T14:08:26+00:00"
         },
         {
             "name": "symfony/polyfill-ctype",
@@ -3399,25 +3251,25 @@
         },
         {
             "name": "symfony/process",
-            "version": "v4.4.4",
+            "version": "v5.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/process.git",
-                "reference": "f5697ab4cb14a5deed7473819e63141bf5352c36"
+                "reference": "f9ffd870f5ac01abec7b2b5e15f904ca9400ecd1"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/process/zipball/f5697ab4cb14a5deed7473819e63141bf5352c36",
-                "reference": "f5697ab4cb14a5deed7473819e63141bf5352c36",
+                "url": "https://api.github.com/repos/symfony/process/zipball/f9ffd870f5ac01abec7b2b5e15f904ca9400ecd1",
+                "reference": "f9ffd870f5ac01abec7b2b5e15f904ca9400ecd1",
                 "shasum": ""
             },
             "require": {
-                "php": "^7.1.3"
+                "php": "^7.2.5"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "4.4-dev"
+                    "dev-master": "5.0-dev"
                 }
             },
             "autoload": {
@@ -3444,7 +3296,7 @@
             ],
             "description": "Symfony Process Component",
             "homepage": "https://symfony.com",
-            "time": "2020-01-09T09:50:08+00:00"
+            "time": "2020-01-09T09:53:06+00:00"
         },
         {
             "name": "symfony/service-contracts",
@@ -3556,27 +3408,27 @@
         },
         {
             "name": "symfony/yaml",
-            "version": "v4.4.4",
+            "version": "v5.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/yaml.git",
-                "reference": "cd014e425b3668220adb865f53bff64b3ad21767"
+                "reference": "69b44e3b8f90949aee2eb3aa9b86ceeb01cbf62a"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/yaml/zipball/cd014e425b3668220adb865f53bff64b3ad21767",
-                "reference": "cd014e425b3668220adb865f53bff64b3ad21767",
+                "url": "https://api.github.com/repos/symfony/yaml/zipball/69b44e3b8f90949aee2eb3aa9b86ceeb01cbf62a",
+                "reference": "69b44e3b8f90949aee2eb3aa9b86ceeb01cbf62a",
                 "shasum": ""
             },
             "require": {
-                "php": "^7.1.3",
+                "php": "^7.2.5",
                 "symfony/polyfill-ctype": "~1.8"
             },
             "conflict": {
-                "symfony/console": "<3.4"
+                "symfony/console": "<4.4"
             },
             "require-dev": {
-                "symfony/console": "^3.4|^4.0|^5.0"
+                "symfony/console": "^4.4|^5.0"
             },
             "suggest": {
                 "symfony/console": "For validating YAML files using the lint command"
@@ -3584,7 +3436,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "4.4-dev"
+                    "dev-master": "5.0-dev"
                 }
             },
             "autoload": {
@@ -3611,7 +3463,139 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "time": "2020-01-21T11:12:16+00:00"
+            "time": "2020-01-21T11:12:28+00:00"
+        },
+        {
+            "name": "thecodingmachine/safe",
+            "version": "v0.1.16",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/thecodingmachine/safe.git",
+                "reference": "4e8f840f0a0a2ea167813c3994a7fc527c3c2182"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/thecodingmachine/safe/zipball/4e8f840f0a0a2ea167813c3994a7fc527c3c2182",
+                "reference": "4e8f840f0a0a2ea167813c3994a7fc527c3c2182",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7.1"
+            },
+            "require-dev": {
+                "phpstan/phpstan": "^0.10.3",
+                "squizlabs/php_codesniffer": "^3.2",
+                "thecodingmachine/phpstan-strict-rules": "^0.10.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.1-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Safe\\": [
+                        "lib/",
+                        "generated/"
+                    ]
+                },
+                "files": [
+                    "generated/apache.php",
+                    "generated/apc.php",
+                    "generated/apcu.php",
+                    "generated/array.php",
+                    "generated/bzip2.php",
+                    "generated/classobj.php",
+                    "generated/com.php",
+                    "generated/cubrid.php",
+                    "generated/curl.php",
+                    "generated/datetime.php",
+                    "generated/dir.php",
+                    "generated/eio.php",
+                    "generated/errorfunc.php",
+                    "generated/exec.php",
+                    "generated/fileinfo.php",
+                    "generated/filesystem.php",
+                    "generated/filter.php",
+                    "generated/fpm.php",
+                    "generated/ftp.php",
+                    "generated/funchand.php",
+                    "generated/gmp.php",
+                    "generated/gnupg.php",
+                    "generated/hash.php",
+                    "generated/ibase.php",
+                    "generated/ibmDb2.php",
+                    "generated/iconv.php",
+                    "generated/image.php",
+                    "generated/imap.php",
+                    "generated/info.php",
+                    "generated/ingres-ii.php",
+                    "generated/inotify.php",
+                    "generated/json.php",
+                    "generated/ldap.php",
+                    "generated/libevent.php",
+                    "generated/libxml.php",
+                    "generated/lzf.php",
+                    "generated/mailparse.php",
+                    "generated/mbstring.php",
+                    "generated/misc.php",
+                    "generated/msql.php",
+                    "generated/mssql.php",
+                    "generated/mysql.php",
+                    "generated/mysqli.php",
+                    "generated/mysqlndMs.php",
+                    "generated/mysqlndQc.php",
+                    "generated/network.php",
+                    "generated/oci8.php",
+                    "generated/opcache.php",
+                    "generated/openssl.php",
+                    "generated/outcontrol.php",
+                    "generated/password.php",
+                    "generated/pcntl.php",
+                    "generated/pcre.php",
+                    "generated/pdf.php",
+                    "generated/pgsql.php",
+                    "generated/posix.php",
+                    "generated/ps.php",
+                    "generated/pspell.php",
+                    "generated/readline.php",
+                    "generated/rrd.php",
+                    "generated/sem.php",
+                    "generated/session.php",
+                    "generated/shmop.php",
+                    "generated/simplexml.php",
+                    "generated/sockets.php",
+                    "generated/sodium.php",
+                    "generated/solr.php",
+                    "generated/spl.php",
+                    "generated/sqlsrv.php",
+                    "generated/ssdeep.php",
+                    "generated/ssh2.php",
+                    "generated/stats.php",
+                    "generated/stream.php",
+                    "generated/strings.php",
+                    "generated/swoole.php",
+                    "generated/uodbc.php",
+                    "generated/uopz.php",
+                    "generated/url.php",
+                    "generated/var.php",
+                    "generated/xdiff.php",
+                    "generated/xml.php",
+                    "generated/xmlrpc.php",
+                    "generated/yaml.php",
+                    "generated/yaz.php",
+                    "generated/zip.php",
+                    "generated/zlib.php",
+                    "lib/special_cases.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PHP core functions that throw exceptions instead of returning FALSE on error",
+            "time": "2019-06-25T08:45:33+00:00"
         },
         {
             "name": "theseer/tokenizer",
@@ -3702,33 +3686,50 @@
             "time": "2019-11-24T13:36:37+00:00"
         },
         {
-            "name": "zendframework/zend-coding-standard",
-            "version": "1.0.0",
+            "name": "webmozart/path-util",
+            "version": "2.3.0",
             "source": {
                 "type": "git",
-                "url": "https://github.com/zendframework/zend-coding-standard.git",
-                "reference": "893316d2904e93f1c74c1384b6d7d57778299cb6"
+                "url": "https://github.com/webmozart/path-util.git",
+                "reference": "d939f7edc24c9a1bb9c0dee5cb05d8e859490725"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/zendframework/zend-coding-standard/zipball/893316d2904e93f1c74c1384b6d7d57778299cb6",
-                "reference": "893316d2904e93f1c74c1384b6d7d57778299cb6",
+                "url": "https://api.github.com/repos/webmozart/path-util/zipball/d939f7edc24c9a1bb9c0dee5cb05d8e859490725",
+                "reference": "d939f7edc24c9a1bb9c0dee5cb05d8e859490725",
                 "shasum": ""
             },
             "require": {
-                "squizlabs/php_codesniffer": "^2.7"
+                "php": ">=5.3.3",
+                "webmozart/assert": "~1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.6",
+                "sebastian/version": "^1.0.1"
             },
             "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.3-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Webmozart\\PathUtil\\": "src/"
+                }
+            },
             "notification-url": "https://packagist.org/downloads/",
             "license": [
-                "BSD-3-Clause"
+                "MIT"
             ],
-            "description": "Zend Framework coding standard",
-            "keywords": [
-                "Coding Standard",
-                "zf"
+            "authors": [
+                {
+                    "name": "Bernhard Schussek",
+                    "email": "bschussek@gmail.com"
+                }
             ],
-            "time": "2016-11-09T21:30:43+00:00"
+            "description": "A robust cross-platform utility for normalizing, comparing and modifying file paths.",
+            "time": "2015-12-17T08:42:14+00:00"
         }
     ],
     "aliases": [],
diff --git a/phpcs_ruleset.xml b/phpcs_ruleset.xml
index cd18df5..96a97bf 100644
--- a/phpcs_ruleset.xml
+++ b/phpcs_ruleset.xml
@@ -1,23 +1,31 @@
 <?xml version="1.0"?>
-<ruleset name="AlexTartan Coding Standard">
-    <description>AlexTartan Coding Standard</description>
+<ruleset name="Expressive Skeleton coding standard"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="vendor/squizlabs/php_codesniffer/phpcs.xsd">
+    <description>Expressive Skeleton coding standard</description>
 
     <!-- display progress -->
     <arg value="p"/>
     <arg name="colors"/>
 
     <!-- inherit rules from: -->
-    <rule ref="PSR2"/>
+    <rule ref="PSR12"/>
+    <rule ref="Generic.PHP.DeprecatedFunctions"/>
+    <rule ref="Generic.PHP.LowerCaseConstant"/>
+    <rule ref="Generic.PHP.NoSilencedErrors"/>
     <rule ref="Generic.Arrays.DisallowLongArraySyntax"/>
-    <rule ref="Generic.Files.LineLength">
+    <rule ref="Generic.Formatting.DisallowMultipleStatements"/>
+    <rule ref="Generic.Metrics.CyclomaticComplexity"/>
+    <rule ref="Generic.Metrics.NestingLevel">
         <properties>
-            <property name="lineLimit" value="150"/>
-            <property name="absoluteLineLimit" value="150"/>
+            <property name="nestingLevel" value="3"/>
+            <property name="absoluteNestingLevel" value="3"/>
         </properties>
     </rule>
-    <rule ref="Squiz.WhiteSpace.OperatorSpacing">
+    <rule ref="Generic.Files.LineLength">
         <properties>
-            <property name="ignoreNewlines" value="true"/>
+            <property name="lineLimit" value="160"/>
+            <property name="absoluteLineLimit" value="160"/>
         </properties>
     </rule>
     <rule ref="Squiz.WhiteSpace.SuperfluousWhitespace">
@@ -25,4 +33,14 @@
             <property name="ignoreBlankLines" value="false"/>
         </properties>
     </rule>
+    <rule ref="Generic.PHP.NoSilencedErrors">
+        <severity>0</severity>
+    </rule>
+    <rule ref="PSR2.Classes.PropertyDeclaration">
+        <severity>0</severity>
+    </rule>
+
+    <!-- Paths to check -->
+    <file>src</file>
+    <file>test</file>
 </ruleset>
diff --git a/phpstan.neon b/phpstan.neon
index 485f3a4..39f1af2 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -4,6 +4,7 @@ includes:
 	- vendor/phpstan/phpstan-strict-rules/rules.neon
 parameters:
 	level: 7
+	checkMissingIterableValueType: false
 	paths:
 		- src
 		- test
diff --git a/src/Helpers/ArrayHelper.php b/src/Helpers/ArrayHelper.php
index 75e07d9..642033a 100644
--- a/src/Helpers/ArrayHelper.php
+++ b/src/Helpers/ArrayHelper.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartan\Helpers;
diff --git a/src/Helpers/CommandLine.php b/src/Helpers/CommandLine.php
index 8400e75..f2cd6ac 100644
--- a/src/Helpers/CommandLine.php
+++ b/src/Helpers/CommandLine.php
@@ -33,7 +33,7 @@ public function __construct(string $command, ?string $workingDirectory, ?string
         }
     }
 
-    public function withOption($option, $value = null, $separator = ' '): self
+    public function withOption(string $option, string $value = null, string $separator = ' '): self
     {
         $command          = clone $this;
         $command->command .= ' ' . $option;
@@ -44,7 +44,7 @@ public function withOption($option, $value = null, $separator = ' '): self
         return $command;
     }
 
-    public function withArgument($argument): self
+    public function withArgument(string $argument): self
     {
         $command          = clone $this;
         $command->command .= ' ' . escapeshellarg($argument);
@@ -76,14 +76,15 @@ public function exec(array &$output = null, int &$returnVar = null): string
     }
 
     /** @codeCoverageIgnore */
-    public function shell_exec(): ?string
+    public function shellExec(): ?string
     {
         return shell_exec($this->getFullCommand());
     }
 
     /** @codeCoverageIgnore */
-    public function system(&$returnVar = null): ?string
+    public function system(int &$returnVar = null): ?string
     {
+        /** @var string|false $result */
         $result = system($this->getFullCommand(), $returnVar);
 
         return $result === false
@@ -96,4 +97,4 @@ public function passthru(int &$returnValue = null): void
     {
         passthru($this->getFullCommand(), $returnValue);
     }
-}
\ No newline at end of file
+}
diff --git a/src/Helpers/ConsoleHelper.php b/src/Helpers/ConsoleHelper.php
index 4ee3461..d82cf82 100644
--- a/src/Helpers/ConsoleHelper.php
+++ b/src/Helpers/ConsoleHelper.php
@@ -15,7 +15,7 @@ final class ConsoleHelper
     public const COLOR_ERROR   = 'white + red_bg + underline + bold';
 
     /** @var int[] */
-    private static $ansiCodes = [
+    private static array $ansiCodes = [
         'off'        => 0,
         'bold'       => 1,
         'italic'     => 3,
@@ -43,7 +43,7 @@ final class ConsoleHelper
 
     public static function setColor(string $string, string $color): string
     {
-        $callback = static function (string $carry, string $item) {
+        $callback = static function (string $carry, string $item): string {
             return $carry . "\033[" . self::$ansiCodes[trim($item)] . 'm';
         };
 
diff --git a/src/Helpers/DateHelper.php b/src/Helpers/DateHelper.php
index c73dcd7..3a3ff80 100644
--- a/src/Helpers/DateHelper.php
+++ b/src/Helpers/DateHelper.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartan\Helpers;
diff --git a/src/Helpers/EmailAddressHelper.php b/src/Helpers/EmailAddressHelper.php
index aaa9e09..9745f4e 100644
--- a/src/Helpers/EmailAddressHelper.php
+++ b/src/Helpers/EmailAddressHelper.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartan\Helpers;
diff --git a/src/Helpers/ReflectionHelper.php b/src/Helpers/ReflectionHelper.php
index e656250..12d7b39 100644
--- a/src/Helpers/ReflectionHelper.php
+++ b/src/Helpers/ReflectionHelper.php
@@ -5,13 +5,18 @@
 namespace AlexTartan\Helpers;
 
 use ReflectionClass;
+use ReflectionException;
 use ReflectionProperty;
 
 use function get_class;
 
 final class ReflectionHelper
 {
-    /** @param mixed $value */
+    /**
+     * @param mixed $value
+     *
+     * @throws ReflectionException
+     */
     public static function setPrivatePropertyValue(object $object, string $property, $value, string $className = null): void
     {
         if ($className === null) {
@@ -23,7 +28,13 @@ public static function setPrivatePropertyValue(object $object, string $property,
         $reflection->setValue($object, $value);
     }
 
-    /** @return mixed */
+    /**
+     * @param class-string $className
+     *
+     * @return mixed
+     *
+     * @throws ReflectionException
+     */
     public static function getPrivatePropertyValue(object $object, string $propertyName, string $className = null)
     {
         if ($className === null) {
@@ -37,7 +48,11 @@ public static function getPrivatePropertyValue(object $object, string $propertyN
         return $property->getValue($object);
     }
 
-    /** @return mixed */
+    /**
+     * @return mixed
+     *
+     * @throws ReflectionException
+     */
     public static function callPrivateMethod(object $object, string $methodName, array $methodArgs)
     {
         $reflection = new ReflectionClass(get_class($object));
@@ -47,7 +62,13 @@ public static function callPrivateMethod(object $object, string $methodName, arr
         return $method->invokeArgs($object, $methodArgs);
     }
 
-    /** @return int|string */
+    /**
+     * @param class-string $className
+     *
+     * @return int|string
+     *
+     * @throws ReflectionException
+     */
     public static function getConstant(object $object, string $constantName, string $className = null)
     {
         if ($className === null) {
diff --git a/src/Helpers/Stream/GeneratorReadStream.php b/src/Helpers/Stream/GeneratorReadStream.php
index 780cd58..c4d3fcd 100644
--- a/src/Helpers/Stream/GeneratorReadStream.php
+++ b/src/Helpers/Stream/GeneratorReadStream.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartan\Helpers\Stream;
@@ -6,6 +7,7 @@
 use Generator;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
+
 use function in_array;
 use function stream_context_get_default;
 use function stream_context_get_options;
diff --git a/src/Helpers/Stream/StreamException.php b/src/Helpers/Stream/StreamException.php
index 6497d62..98920ce 100644
--- a/src/Helpers/Stream/StreamException.php
+++ b/src/Helpers/Stream/StreamException.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartan\Helpers\Stream;
diff --git a/test/Helpers/ArrayHelperTest.php b/test/Helpers/ArrayHelperTest.php
index f29ebac..74f3845 100644
--- a/test/Helpers/ArrayHelperTest.php
+++ b/test/Helpers/ArrayHelperTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers;
@@ -188,7 +189,7 @@ public function testIndexArrayOfArraysByKeyCanWorkWithDuplicates(): void
 
     private function getTestObjectFromObject(object $param): object
     {
-        return new class($param)
+        return new class ($param)
         {
             /** @var object */
             private $prop;
@@ -207,7 +208,7 @@ public function getProp(): object
 
     private function getTestObjectFromString(string $param): object
     {
-        return new class($param)
+        return new class ($param)
         {
             /** @var string */
             private $prop;
diff --git a/test/Helpers/ConsoleHelperTest.php b/test/Helpers/ConsoleHelperTest.php
index 9f22ca3..a3d66df 100644
--- a/test/Helpers/ConsoleHelperTest.php
+++ b/test/Helpers/ConsoleHelperTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers;
diff --git a/test/Helpers/DateHelperTest.php b/test/Helpers/DateHelperTest.php
index b7bc3a0..07e2636 100644
--- a/test/Helpers/DateHelperTest.php
+++ b/test/Helpers/DateHelperTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers;
diff --git a/test/Helpers/EmailAddressHelperTest.php b/test/Helpers/EmailAddressHelperTest.php
index dc96593..9e38c0b 100644
--- a/test/Helpers/EmailAddressHelperTest.php
+++ b/test/Helpers/EmailAddressHelperTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers;
diff --git a/test/Helpers/ReflectionHelperTest.php b/test/Helpers/ReflectionHelperTest.php
index ffe854b..71efde6 100644
--- a/test/Helpers/ReflectionHelperTest.php
+++ b/test/Helpers/ReflectionHelperTest.php
@@ -16,7 +16,7 @@ final class ReflectionHelperTest extends TestCase
 {
     public function testCallPrivateMethod(): void
     {
-        $x = new class() {
+        $x = new class () {
             /** @noinspection PhpUnusedPrivateMethodInspection */
             private function privateMethod(): int
             {
@@ -32,7 +32,7 @@ private function privateMethod(): int
 
     public function testSetPrivatePropertyValue(): void
     {
-        $x = new class() {
+        $x = new class () {
             /** @var int */
             private $privateProperty;
 
@@ -77,7 +77,7 @@ public function testSetPrivatePropertyValueFromParentClass(): void
 
     public function testGetPrivatePropertyValue(): void
     {
-        $x = new class() {
+        $x = new class () {
             /** @var int */
             private /** @noinspection PhpUnusedPrivateFieldInspection */ $privateProperty = 123;
         };
@@ -91,7 +91,7 @@ public function testGetPrivatePropertyValue(): void
 
     public function testGetPrivateConstant(): void
     {
-        $x = new class() {
+        $x = new class () {
             private const /** @noinspection PhpUnusedPrivateFieldInspection */ TEST = 'testing';
         };
 
diff --git a/test/Helpers/StringHelperTest.php b/test/Helpers/StringHelperTest.php
index 0b46fc9..a1fa07e 100644
--- a/test/Helpers/StringHelperTest.php
+++ b/test/Helpers/StringHelperTest.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers;
diff --git a/test/Helpers/TestAssets/TestLogger.php b/test/Helpers/TestAssets/TestLogger.php
index f126dd0..686a653 100644
--- a/test/Helpers/TestAssets/TestLogger.php
+++ b/test/Helpers/TestAssets/TestLogger.php
@@ -1,9 +1,11 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers\TestAssets;
 
 use Psr\Log\AbstractLogger;
+
 use const PHP_EOL;
 
 class TestLogger extends AbstractLogger
diff --git a/test/Helpers/TestAssets/TestPrivateChild.php b/test/Helpers/TestAssets/TestPrivateChild.php
index cbec5a6..3a77f67 100644
--- a/test/Helpers/TestAssets/TestPrivateChild.php
+++ b/test/Helpers/TestAssets/TestPrivateChild.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers\TestAssets;
diff --git a/test/Helpers/TestAssets/TestPrivateParent.php b/test/Helpers/TestAssets/TestPrivateParent.php
index d6d0f21..4d8129a 100644
--- a/test/Helpers/TestAssets/TestPrivateParent.php
+++ b/test/Helpers/TestAssets/TestPrivateParent.php
@@ -1,4 +1,5 @@
 <?php
+
 declare(strict_types=1);
 
 namespace AlexTartanTest\Helpers\TestAssets;