Add deprecated_reason support for arguments

README.md

@@ -52,6 +52,7 @@ class PostType < GraphQL::Schema::Object
     argument :filter, types.String, required: false
     argument :id, types.ID, required: false
     argument :isPublished, types.Boolean, required: false
+    argument :published, types.String, required: false, deprecation_reason: 'Use isPublished instead'
   end
 end
 ```
@@ -129,6 +130,9 @@ describe PostType do
       expect(subject).to accept_argument(:id).of_type('ID')
     end
 
+    # Check a argument is deprecated
+    it { is_expected.to accept_argument(:published).with_deprecation_reason }
+
     it { is_expected.not_to accept_argument(:weirdo) }
 
     # The gem automatically converts argument names to CamelCase, so this will
@@ -207,6 +211,15 @@ This project is intended to be a safe, welcoming space for collaboration, and
 contributors are expected to adhere to the
 [Contributor Covenant](http://contributor-covenant.org) code of conduct.
 
+## Testing
+
+```
+gem install diff-lcs
+bundle install
+```
+
+Run tests!
+
 ## License
 
 The gem is available as open source under the terms of the

lib/rspec/graphql_matchers/accept_argument.rb

@@ -2,6 +2,7 @@
 
 require_relative 'base_matcher'
 require_relative './have_a_field_matchers/of_type'
+require_relative './have_a_field_matchers/with_deprecation_reason'
 
 module RSpec
   module GraphqlMatchers
@@ -43,6 +44,11 @@ def of_type(expected_field_type)
         self
       end
 
+      def with_deprecation_reason(expected_reason = nil)
+        @expectations << HaveAFieldMatchers::WithDeprecationReason.new(expected_reason)
+        self
+      end
+
       def failure_message
         base_msg = "expected #{member_name(@graph_object)} " \
           "to accept argument `#{@expected_arg_name}`" \

spec/rspec/accept_argument_matcher_spec.rb

@@ -106,10 +106,22 @@ module GraphqlMatchers
             argument :is_test, GraphQL::Types::Boolean, required: false
             argument :not_camelized, GraphQL::Types::Boolean, required: false,
                                                               camelize: false
+            argument :deprecated_argument, types.String, required: false,
+                                                         deprecation_reason: 'deprecated'
+
           end
         end
 
         include_examples 'accept argument'
+
+        describe '.with_deprecation_reason' do
+          let(:deprecated_argument) { :deprecated_argument }
+
+          it 'passes when the deprecation reasons match' do
+            expect(a_type).to accept_argument(deprecated_argument)
+              .with_deprecation_reason('deprecated')
+          end
+        end
       end
 
       context 'with legacy DSL api' do