TASK: Support at least PHP 5.6

* Adjust CI , composer and docs.
* Migrate modern code to 5.6 supported code.

Relates: #71

.gitlab-ci.yml

@@ -41,12 +41,20 @@ lint:php-mass-detection:
   script:
     - ./vendor/bin/phpmd src text phpmd.xml > result/phpmd.txt
 
-test:7.1: &PHP-UNITTESTING
+test:5.6: &PHP-UNITTESTING
-  image: php:7.1-alpine
+  image: php:5.6-alpine
   stage: test
   script:
     - ./vendor/bin/phpunit
 
+test:7.0:
+  <<: *PHP-UNITTESTING
+  image: php:7.0-alpine
+
+test:7.1:
+  <<: *PHP-UNITTESTING
+  image: php:7.1-alpine
+
 test:latest:
   <<: *PHP-UNITTESTING
   image: php:7-alpine

Documentation/source/index.rst

@@ -19,7 +19,8 @@ Requirements
 To install the project you need ``composer`` to be installed and inside your ``$PATH``.
 Otherwise run ``make install-composer`` to install composer.
 
-At least PHP 7.1 is required.
+We recommend to use at least PHP 5.6, we do not test with lower versions as 5.6 is latest maintained
+version.
 
 Installation
 ============

composer.json

@@ -23,7 +23,7 @@
         ]
     },
     "require": {
-        "php": "~7.1",
+        "php": ">=5.6",
         "helmich/typo3-typoscript-parser": "1.1.*",
         "squizlabs/php_codesniffer": "2.8.*",
         "symfony/yaml": "3.2.*",

src/Standards/Typo3Update/Feature/AbstractYamlRemovedUsage.php

@@ -49,10 +49,17 @@ abstract class AbstractYamlRemovedUsage implements FeatureInterface
         $this->sniff = $sniff;
         $this->configured = new RemovedByYamlConfiguration(
             $this->getRemovedConfigFiles(),
-            \Closure::fromCallable([$this, 'prepareStructure'])
+            $this->getPrepateStructure()
         );
     }
 
+    protected function getPrepateStructure()
+    {
+        return function (array $typo3Versions) {
+            return call_user_func_array([$this, 'prepareStructure'], [$typo3Versions]);
+        };
+    }
+
     /**
      * Prepares structure from config for later usage.
      *

src/Standards/Typo3Update/Sniffs/Removed/AbstractGenericUsage.php

@@ -39,10 +39,17 @@ abstract class AbstractGenericUsage implements PhpCsSniff
     {
         $this->configured = new RemovedByYamlConfiguration(
             $this->getRemovedConfigFiles(),
-            \Closure::fromCallable([$this, 'prepareStructure'])
+            $this->getPrepateStructure()
         );
     }
 
+    protected function getPrepateStructure()
+    {
+        return function (array $typo3Versions) {
+            return call_user_func_array([$this, 'prepareStructure'], [$typo3Versions]);
+        };
+    }
+
     /**
      * Prepares structure from config for later usage.
      *