Fix argument overwrite (#44)

* Fix argument overwrite when using setArguments on ProcessBuilder

Author: maschmann

Ansible/Process/ProcessBuilder.php

@@ -63,7 +63,11 @@ public function __construct(string $prefix, string $path)
      */
     public function setArguments(array $arguments): ProcessBuilderInterface
     {
-        $this->arguments = $arguments;
+        if (!empty($this->arguments)) {
+            $this->arguments = array_merge($this->arguments, $arguments);
+        } else {
+            $this->arguments = $arguments;
+        }
 
         return $this;
     }

Tests/Ansible/Process/ProcessBuilderTest.php

@@ -37,12 +37,15 @@ public function testCreateInstance()
     public function testGetProcess(ProcessBuilderInterface $processBuilder)
     {
         $process = $processBuilder
-            ->setArguments([])
+            ->setArguments(['more_args'])
             ->setEnv('SOME', 'value')
             ->setTimeout(5)
             ->getProcess();
 
         $this->assertInstanceOf(Process::class, $process);
+
+        // verify, all args are kept and merged correctly
+        $this->assertEquals("'{$this->getGalaxyUri()}' 'more_args'", $process->getCommandLine());
     }
 }