feat(argument): Change how glue is defined

For the mergeable argument.

BREAKING CHANGE: IMergeableArgument::glue() is now static.

Author: Antoine Aflalo

src/Request/Api/BaseRequest.php

@@ -60,7 +60,7 @@ public function addArgument(IArgument $arg): IRequest
     {
         if ($arg instanceof IMergeableArgument) {
             if (!isset($this->mergeableArguments[$arg->getKey()])) {
-                $this->mergeableArguments[$arg->getKey()] = new ArgMerger();
+                $this->mergeableArguments[$arg->getKey()] = new ArgMerger($arg::glue());
             }
 
             $this->mergeableArguments[$arg->getKey()]->addArgument($arg);

src/Request/Arguments/Mergeable/ArgMerger.php

@@ -12,11 +12,28 @@
 
 class ArgMerger implements PrimalValued
 {
+
+    /**
+     * @var string
+     */
+    private $glue;
+
+
     /**
      * @var IMergeableArgument[]
      */
     private $args = [];
 
+    /**
+     * ArgMerger constructor.
+     *
+     * @param string $glue
+     */
+    public function __construct(string $glue)
+    {
+        $this->glue = $glue;
+    }
+
     /**
      * Add the argument.
      *
@@ -58,7 +75,7 @@ public function toPrimitive()
 
         $values = array_keys($this->args);
 
-        return implode($this->args[$values[0]]->glue(), $values);
+        return implode($this->glue, $values);
     }
 
     /**

src/Request/Arguments/Mergeable/IMergeableArgument.php

@@ -24,5 +24,5 @@ interface IMergeableArgument extends IArgument
      *
      * @return string
      */
-    public function glue();
+    public static function glue();
 }

tests/src/Base/Argument/TestMergeableArg.php

@@ -42,7 +42,7 @@ public function getKey(): string
      *
      * @return string
      */
-    public function glue()
+    public static function glue()
     {
         return ';';
     }