errors: Return parse error if more than one argument (#2472)

* Check errors directive only has 1 argument

* Added Tests

caddyhttp/errors/setup.go

@@ -123,6 +123,10 @@ func errorsParse(c *caddy.Controller) (*ErrorHandler, error) {
 			}
 		}
 
+		if len(args) > 1 {
+			return handler, c.Errf("Only 1 Argument expected for errors directive")
+		}
+
 		// Configuration may be in a block
 		err := optionalBlock()
 		if err != nil {

caddyhttp/errors/setup_test.go

@@ -179,6 +179,11 @@ func TestErrorsParse(t *testing.T) {
 			* generic_error.html
 			* generic_error.html
 		}`, true, ErrorHandler{ErrorPages: map[int]string{}, Log: &httpserver.Logger{}}},
+		{`errors /path error.txt {
+			404 
+		}`, true, ErrorHandler{ErrorPages: map[int]string{}, Log: &httpserver.Logger{}}},
+
+		{`errors /path error.txt`, true, ErrorHandler{ErrorPages: map[int]string{}, Log: &httpserver.Logger{}}},
 	}
 
 	for i, test := range tests {