From 6511c0585190f5c4174c526055baeae1ce962a69 Mon Sep 17 00:00:00 2001
From: Vlad Faust <mail@vladfaust.com>
Date: Fri, 19 Oct 2018 13:31:46 +0300
Subject: [PATCH] refactor: prettier error on null JSON parsing

---
 src/params.cr | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/params.cr b/src/params.cr
index 206db58..1c70b3f 100644
--- a/src/params.cr
+++ b/src/params.cr
@@ -348,8 +348,15 @@ module Params
 
                     @initialized[{{key}}] = true
                   rescue ex : JSON::ParseException
-                    value = pull.read_raw
-                    raise ::Params::TypeCastError.new(value, value.class.name, {{value["defined_type"].stringify}}, {{key}}, @path)
+                    value = "null"
+                    klass = "Null"
+
+                    pull.read_null_or do
+                      value = pull.read_raw
+                      klass = value.class.name
+                    end
+
+                    raise ::Params::TypeCastError.new(value, klass, {{value["defined_type"].stringify}}, {{key}}, @path)
                   end
                 {% end %}
             {% end %}