1 files changed, 28 insertions, 0 deletions
diff --git a/spec/support/matchers/disambiguate_attributes.rb b/spec/support/matchers/disambiguate_attributes.rb
new file mode 100644
index 0000000000..bc4a5215d4
--- /dev/null
+++ b/spec/support/matchers/disambiguate_attributes.rb
@@ -0,0 +1,28 @@
+module DisambiguateAttributesMatcher
+  class DisambiguateAttributes
+    def initialize(attributes)
+      @attributes = attributes
+    end
+
+    def matches?(actual)
+      @actual = actual
+      attribute1, attribute2 = @attributes
+      @actual[attribute1].descends_from?(attribute1) &&
+        !@actual[attribute1].descends_from?(attribute2) &&
+        @actual[attribute2].descends_from?(attribute2)
+    end
+
+    def failure_message
+      ""
+      # "expected #{@actual} to disambiguate its attributes"
+    end
+
+    def negative_failure_message
+      "expected #{@actual} to not disambiguate its attributes"
+    end
+  end
+
+  def disambiguate_attributes(*attributes)
+    DisambiguateAttributes.new(attributes)
+  end
+end