Skip validation if overrides are allowed at construction time.

src/ServiceManager.php

@@ -170,7 +170,7 @@ public function __construct(array $config = [])
             $this->resolveAbstractFactories(null);
         }
 
-        $this->configure($config);
+        $this->configureSkippingOverrideValidation($config);
     }
 
     /**
@@ -291,7 +291,27 @@ public function getAllowOverride()
     }
 
     /**
-     * Configure the service manager
+     * Configure the service manager applying validation that overrides
+     * are allowed
+     *
+     * @see configureSkippingOverrideValidation below
+     *
+     * @param  array $config
+     * @return self
+     * @throws ContainerModificationsNotAllowedException if the allow
+     *     override flag has been toggled off, and a service instance
+     *     exists for a given service.
+     */
+    public function configure(array $config)
+    {
+        $this->validateOverrides($config);
+        $this->configureSkippingOverrideValidation($config);
+        return $this;
+    }
+
+    /**
+     * Configure the service manager without applying validation that override
+     * is allowed (called by __construct directly)
      *
      * Valid top keys are:
      *
@@ -325,15 +345,12 @@ public function getAllowOverride()
      *   should be shared by default.
      *
      * @param  array $config
-     * @return self
      * @throws ContainerModificationsNotAllowedException if the allow
      *     override flag has been toggled off, and a service instance
      *     exists for a given service.
      */
-    public function configure(array $config)
+    private function configureSkippingOverrideValidation($config)
     {
-        $this->validateOverrides($config);
-
         if (isset($config['services'])) {
             $this->services = $config['services'] + $this->services;
         }
@@ -382,8 +399,6 @@ public function configure(array $config)
         }
 
         $this->configured = true;
-
-        return $this;
     }
 
     /**