feat: Add RSpec matchers

lib/amazing_activist/rspec.rb

@@ -0,0 +1,3 @@
+# frozen_string_literal: true
+
+require_relative "./rspec/matchers"

lib/amazing_activist/rspec/matchers.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require_relative "./matchers/be_a_failure"
+require_relative "./matchers/be_a_success"
+
+module AmazingActivist
+  module RSpec
+    module Matchers
+      UNDEFINED = Object.new.freeze
+
+      # @example With any code and any originator
+      #   expect(outcome).to be_a_failure
+      #
+      # @example With specific code
+      #   expect(outcome).to be_a_failure(:bad)
+      def be_a_failure(...)
+        BeAFailure.new(...)
+      end
+
+      # @example With any value
+      #   expect(outcome).to be_a_success
+      #
+      # @example With value
+      #   expect(outcome).to be_a_success(42)
+      def be_a_success(...)
+        BeASuccess.new(...)
+      end
+    end
+  end
+end

lib/amazing_activist/rspec/matchers/be_a_failure.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+module AmazingActivist
+  module RSpec
+    module Matchers
+      class BeAFailure
+        include ::RSpec::Matchers::Composable
+
+        def initialize(code = UNDEFINED)
+          @actual = nil
+          @code   = code
+        end
+
+        def with_code(code)
+          @code = code
+          self
+        end
+
+        def matches?(actual)
+          @actual = actual
+
+          return false unless actual.is_a?(AmazingActivist::Outcome::Failure)
+          return false unless any_code? || values_match?(@code, actual.code)
+
+          true
+        end
+
+        def description
+          "be an AmazingActivist::Outcome::Failure"
+        end
+
+        def failure_message
+          message = "expected #{actual_formatted}\nto #{description}"
+          message << "\nwith code: #{::RSpec::Support::ObjectFormatter.format(@code)}" unless any_code?
+
+          message
+        end
+
+        private
+
+        def any_code?
+          @code == UNDEFINED
+        end
+
+        def actual_formatted
+          ::RSpec::Support::ObjectFormatter.format(@actual)
+        end
+      end
+    end
+  end
+end

lib/amazing_activist/rspec/matchers/be_a_success.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+module AmazingActivist
+  module RSpec
+    module Matchers
+      class BeASuccess
+        include ::RSpec::Matchers::Composable
+
+        def initialize(value = UNDEFINED)
+          @actual = nil
+          @value  = value
+        end
+
+        def with_value(value)
+          @value = value
+          self
+        end
+
+        def matches?(actual)
+          @actual = actual
+
+          return false unless actual.is_a?(AmazingActivist::Outcome::Success)
+          return false unless any_value? || values_match?(@value, actual.unwrap!)
+
+          true
+        end
+
+        def description
+          "be an AmazingActivist::Outcome::Success"
+        end
+
+        def failure_message
+          message = "expected #{actual_formatted}\nto #{description}"
+          message << "\nwith value: #{::RSpec::Support::ObjectFormatter.format(@value)}" unless any_value?
+
+          message
+        end
+
+        private
+
+        def any_value?
+          @value == UNDEFINED
+        end
+
+        def actual_formatted
+          ::RSpec::Support::ObjectFormatter.format(@actual)
+        end
+      end
+    end
+  end
+end