Move hash symbolizer into a helper, prevent namespace conflicts

lib/rails_admin.rb

@@ -7,7 +7,7 @@
 require 'rails_admin/extensions/paper_trail'
 require 'rails_admin/extensions/history'
 require 'rails_admin/support/csv_converter'
-require 'rails_admin/support/core_extensions'
+require 'rails_admin/support/hash_helper'
 
 module RailsAdmin
   # Setup RailsAdmin

lib/rails_admin/config/actions/export.rb

@@ -16,7 +16,7 @@ class Export < RailsAdmin::Config::Actions::Base
           proc do
             if format = params[:json] && :json || params[:csv] && :csv || params[:xml] && :xml
               request.format = format
-              @schema = params[:schema].symbolize if params[:schema] # to_json and to_xml expect symbols for keys AND values.
+              @schema = HashHelper.symbolize(params[:schema]) if params[:schema] # to_json and to_xml expect symbols for keys AND values.
               @objects = list_entries(@model_config, :export)
               index
             else

lib/rails_admin/support/hash_helper.rb

@@ -0,0 +1,28 @@
+module RailsAdmin
+  class HashHelper
+    def self.symbolize(obj)
+      case obj
+      when Array
+        obj.each_with_object([]) do |val, res|
+          res << case val
+                 when Hash, Array then symbolize(val)
+                 when String      then val.to_sym
+                 else val
+                 end
+        end
+      when Hash
+        obj.each_with_object({}) do |(key, val), res|
+          nkey = key.is_a?(String) ? key.to_sym : key
+          nval = case val
+                 when Hash, Array then symbolize(val)
+                 when String      then val.to_sym
+                 else val
+                 end
+          res[nkey] = nval
+        end
+      else
+        obj
+      end
+    end
+  end
+end

spec/rails_admin/support/hash_helper_spec.rb

@@ -0,0 +1,37 @@
+# encoding: utf-8
+
+require 'spec_helper'
+
+describe RailsAdmin::HashHelper do
+  let(:hash) do
+    {'subject' => 'Test',
+     'user' => {name: 'Dirk',
+                'title' => 'Holistic Detective',
+                'clients' => [
+                  {name: 'Zaphod'},
+                  {'name' => 'Arthur'}]}}
+  end
+
+  describe 'symbolize' do
+    let(:symbolized_hash) { RailsAdmin::HashHelper.symbolize(hash) }
+
+    it 'symbolizes top-level hash keys' do
+      [:subject, :user].each do |key|
+        expect(symbolized_hash.keys).to include(key)
+      end
+    end
+
+    it 'symbolizes nested hashes' do
+      [:name, :title, :clients].each do |key|
+        expect(symbolized_hash[:user].keys).to include(key)
+      end
+    end
+
+    it 'symbolizes nested hashes inside of array values' do
+      clients = symbolized_hash[:user][:clients]
+      expect(clients.length).to eq(2)
+      expect(clients[0][:name]).to eq(:Zaphod)
+      expect(clients[1][:name]).to eq(:Arthur)
+    end
+  end
+end