Proposal: Inform user when testing a private method

Gemfile

@@ -29,5 +29,3 @@ gem 'contracts', '< 0.16' if RUBY_VERSION < '1.9.0'
 gem 'coveralls', :require => false, :platform => :mri_20
 
 eval File.read('Gemfile-custom') if File.exist?('Gemfile-custom')
-
-gem 'pry'

features/its.feature

@@ -51,7 +51,7 @@ Feature: attribute of subject
             person
           end
 
-          its("phone_numbers.first") { should eq("555-1212") }
+          its("phone_numbers.first") { is_expected.to eq("555-1212") }
         end
       end
       """
@@ -61,7 +61,7 @@ Feature: attribute of subject
       Person
         with one phone number (555-1212)
           phone_numbers.first
-            should eq "555-1212"
+            is expected to eq "555-1212"
       """
 
   Scenario: specify value of an attribute of a hash

lib/rspec/its.rb

@@ -1,6 +1,14 @@
 require 'rspec/its/version'
 require 'rspec/core'
 
+RSpec.deprecate <<EOS
+rspec-its deprecates calling _send_ in favour of _public_send_ internally.
+This change will be introduced with version 2.0.
+Maybe you're testing private methods in your test suite without your intention.
+If you need more information about which test is affected,
+set `config.its_raise_errors_for_private_method_calling = true`
+EOS
+
 module RSpec
   module Its
 
@@ -95,7 +103,7 @@ module Its
     #
     #   # This ...
     #   describe Array do
-    #     its(:size, focus: true) { should eq(0) }
+    #     its(:size, :focus) { should eq(0) }
     #   end
     #
     #   # ... generates the same runtime structure as this:
@@ -132,30 +140,18 @@ def its(attribute, *options, &block)
             attribute_chain = attribute.to_s.split('.')
             attribute_chain.inject(subject) do |inner_subject, attr|
 
-              # When NilClass:   user didnt set the rspec setting
-              # When FalseClass: skip this block
-              if RSpec.configuration.its_private_method_debug.is_a? NilClass
+              if RSpec.configuration.its_raise_errors_for_private_method_calling
 
                 # respond_to? only looks in the public method space
                 # TODO Check NoMethodError
                 # TODO Check if inner_subject some kind of const
                 # inner_subject.method_defined?(attr) && !inner_subject.respond_to?(attr)
                 if !inner_subject.respond_to?(attr)
-
-                  if RSpec.configuration.its_private_method_debug
-                    # TODO if debug: show spec:line_num for better indication
-                    puts its_caller.first
-                  end
-
-                  puts "You are testing a private method. Set RSpec its_private_method_debug setting to show more info or hide it completly."
-
-                  # TODO Add deprecation warning to drop private method calling
-                  # for the next major release
+                  raise 'Testing private method' + attr
                 end
               end
 
               inner_subject.send(attr)
-
             end
           end
         end
@@ -202,7 +198,7 @@ def should_not(matcher=nil, message=nil)
 
   # Add RSpec configuration setting to allow
   # the user to handle private method invoking warning
-  rspec.add_setting :its_private_method_debug
+  rspec.add_setting :its_raise_errors_for_private_method_calling
 
   rspec.extend RSpec::Its
   rspec.backtrace_exclusion_patterns << %r(/lib/rspec/its)

spec/rspec/its_spec.rb

@@ -9,19 +9,36 @@ module RSpec
           its([]) { expect(described_class).to be Its }
         end
       end
-      context "" do
+
+      context "raises error when calling a private method" do
+        around(:each) do |example|
+          RSpec.configuration.its_raise_errors_for_private_method_calling = true
+          example.run
+          RSpec.configuration.its_raise_errors_for_private_method_calling = false
+        end
+
         subject do
           Class.new do
             private
 
             def name
-              'Maria'
             end
-          end.new
+
+            def self.name
+            end
+            private_class_method :name
+          end
+        end
+
+        context 'on an instance' do
+          its('new.name') { will raise_error }
         end
 
-        its(:name, :focus) { should eq('Maria') }
+        context 'on a class' do
+          its('name') { will raise_error }
+        end
       end
+
       context "with explicit subject" do
         subject do
           Class.new do