Fix dig bug for Array

CHANGELOG.md

@@ -29,6 +29,7 @@ scheme are considered to be bugs.
 ### Fixed
 
 * [#369](https://github.com/intridea/hashie/pull/369): If a translation for a property exists when using IndifferentAccess and IgnoreUndeclared, use the translation to find the property - [@whitethunder](https://github.com/whitethunder).
+* [#376](https://github.com/intridea/hashie/pull/376): Leave string index unchanged if it can't be converted to integer for Array#dig - [@sazor](https://github.com/sazor).
 
 ### Security
 

lib/hashie/array.rb

@@ -7,7 +7,14 @@ module Hashie
     include Hashie::Extensions::RubyVersionCheck
     with_minimum_ruby('2.3.0') do
       def dig(*indexes)
-        super(*indexes.map { |idx| Integer(idx) })
+        converted_indexes = indexes.map do |idx|
+          begin
+            Integer(idx)
+          rescue ArgumentError
+            idx
+          end
+        end
+        super(*converted_indexes)
       end
     end
   end

spec/hashie/array_spec.rb

@@ -12,6 +12,18 @@ describe Array do
       it 'works with a numeric index' do
         expect(array.dig(1)).to eq(:b)
       end
+
+      context 'when array is empty' do
+        let(:array) { Hashie::Array.new([]) }
+
+        it 'works with a first numeric and next string index' do
+          expect(array.dig(0, 'hello')).to eq(nil)
+        end
+
+        it 'throws an error with first string and next numeric index' do
+          expect { array.dig('hello', 0) }.to raise_error(TypeError)
+        end
+      end
     end
   end
 end