Merge branch 'master' into feature/III-1772

# Conflicts:
#	composer.json

tests/OfferSearchControllerTest.php

@@ -356,6 +356,30 @@ public function it_sets_a_default_available_from_and_available_to_if_none_are_gi
         $this->controller->search($request);
     }
 
+    /**
+     * @test
+     */
+    public function it_expects_a_valid_available_from_and_available_to_date()
+    {
+        $request = Request::create(
+            'http://search.uitdatabank.be/offers/',
+            'GET',
+            [
+                'start' => 0,
+                'limit' => 0,
+                'availableFrom' => '2017-04-01',
+                'availableTo' => '2017-04-01',
+            ]
+        );
+
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage(
+            'availableFrom should be an ISO-8601 datetime, for example 2017-04-26T12:20:05+01:00'
+        );
+
+        $this->controller->search($request);
+    }
+
     /**
      * @test
      */