Add have_a_version_with_changes matcher

CHANGELOG.md

@@ -18,7 +18,8 @@ recommendations of [keepachangelog.com](http://keepachangelog.com/).
 
 ### Added
 
-- None
+- [#881](https://github.com/airblade/paper_trail/pull/881) - Add RSpec matcher
+  `have_a_version_with_changes` for easier testing.
 
 ### Fixed
 

README.md

@@ -1392,7 +1392,8 @@ end
 ```
 
 It is also possible to do assertions on the versions using `have_a_version_with`
-matcher
+and `have_a_version_with_changes` matchers. For more examples, see the
+[Widget spec](https://github.com/airblade/paper_trail/blob/master/spec/models/widget_spec.rb)
 
 ```ruby
 describe '`have_a_version_with` matcher' do

lib/paper_trail/frameworks/rspec.rb

@@ -27,3 +27,8 @@
   # check if the model has a version with the specified attributes
   match { |actual| actual.versions.where_object(attributes).any? }
 end
+
+RSpec::Matchers.define :have_a_version_with_changes do |attributes|
+  # check if the model has a version changes with the specified attributes
+  match { |actual| actual.versions.where_object_changes(attributes).any? }
+end

spec/models/widget_spec.rb

@@ -21,6 +21,20 @@
     end
   end
 
+  describe "`have_a_version_with_changes` matcher", versioning: true do
+    before do
+      widget.update_attributes!(name: "Leonard", an_integer: 2)
+      widget.update_attributes!(name: "Tom")
+      widget.update_attributes!(name: "Bob")
+    end
+
+    it "is possible to do assertions on versions" do
+      expect(widget).to have_a_version_with_changes name: "Leonard", an_integer: 2
+      expect(widget).to have_a_version_with_changes an_integer: 2
+      expect(widget).to have_a_version_with_changes name: "Tom"
+    end
+  end
+
   describe "versioning option" do
     context "enabled", versioning: true do
       it "should enable versioning" do