diff --git a/.travis.yml b/.travis.yml
index 6b5689b..a541dd5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,6 @@
 language: ruby
 rvm:
+  - 2.5.0
   - 2.4.0
   - 2.3.0
   - 2.2.2
diff --git a/lib/flexirest/base_without_validation.rb b/lib/flexirest/base_without_validation.rb
index 3d39252..6633fdc 100644
--- a/lib/flexirest/base_without_validation.rb
+++ b/lib/flexirest/base_without_validation.rb
@@ -13,7 +13,7 @@ class BaseWithoutValidation
     attr_accessor :_headers
 
     instance_methods.each do |m|
-      next unless %w{display presence load require hash untrust trust freeze method enable_warnings with_warnings suppress capture silence quietly debugger breakpoint}.map(&:to_sym).include? m
+      next unless %w{display presence load require untrust trust freeze method enable_warnings with_warnings suppress capture silence quietly debugger breakpoint}.map(&:to_sym).include? m
       undef_method m
     end
 
diff --git a/spec/lib/ruby_core_spec.rb b/spec/lib/ruby_core_spec.rb
new file mode 100644
index 0000000..f596860
--- /dev/null
+++ b/spec/lib/ruby_core_spec.rb
@@ -0,0 +1,12 @@
+require 'spec_helper'
+
+class EmptyExample < Flexirest::BaseWithoutValidation
+  whiny_missing true
+end
+
+describe Flexirest::BaseWithoutValidation do
+  it 'should support hash resolving' do
+    h = {}
+    expect{ h[EmptyExample.new] = 'not important' }.to_not raise_error
+  end
+end
\ No newline at end of file