ArgumentError doesn’t take arguments

Seems this codepath wasn’t tested ever so adding a test so that we’re covered.

Author: Temikus

lib/fog/compute/google/models/servers.rb

@@ -109,7 +109,7 @@ def get_public_key(public_key_path)
           end
 
           if public_key_path.nil? || public_key_path.empty?
-            raise ArgumentError("cannot bootstrap instance without public key file")
+            raise Fog::Errors::Error.new("Cannot bootstrap instance without a public key")
           end
 
           File.read(File.expand_path(public_key_path))

test/integration/compute/test_servers.rb

@@ -41,6 +41,14 @@ def test_bootstrap
                  "Bootstrapped server should have an external ip by default")
     end
   end
+
+  def test_bootstrap_fail
+    # Pretend the ssh key does not exist
+    File.stub :exist?, nil do
+      assert_raises(Fog::Errors::Error) {
+        @subject.bootstrap(:name => "#{CollectionFactory::PREFIX}-#{Time.now.to_i}",
+                           :public_key_path => nil)
+      }
     end
   end
 end