policy_info.rb in pundit-matchers-3.0.0.beta1

- old
+ new
@@ -1,30 +1,91 @@
 # frozen_string_literal: true
 
 module Pundit
   module Matchers
     module Utils
-      # Collects all details about given policy class.
+      # This class provides methods to retrieve information about a policy class,
+      # such as the actions it defines and which of those actions are permitted
+      # or forbidden. It also provides a string representation of the policy class name
+      # and the user object associated with the policy.
       class PolicyInfo
+        # Error message when policy does not respond to `user_alias`.
+        USER_NOT_IMPLEMENTED_ERROR = <<~MSG
+          '%<policy>s' does not implement '%<user_alias>s'. You may want to
+          configure an alias, which you can do as follows:
+
+          Pundit::Matchers.configure do |config|
+            # Alias for all policies
+            config.default_user_alias = :%<user_alias>s
+
+            # Per-policy alias
+            config.user_aliases = { '%<policy>s' => :%<user_alias>s }
+          end
+        MSG
+
         attr_reader :policy
 
+        # Initializes a new instance of PolicyInfo.
+        #
+        # @param policy [Class] The policy class to collect details about.
         def initialize(policy)
           @policy = policy
+          check_user_alias!
         end
 
+        # Returns a string representation of the policy class name.
+        #
+        # @return [String] A string representation of the policy class name.
+        def to_s
+          policy.class.name
+        end
+
+        # Returns the user object associated with the policy.
+        #
+        # @return [Object] The user object associated with the policy.
+        def user
+          @user ||= policy.public_send(user_alias)
+        end
+
+        # Returns an array of all actions defined in the policy class.
+        #
+        # It assumes that actions are defined as public instance methods that end with a question mark.
+        #
+        # @return [Array<Symbol>] An array of all actions defined in the policy class.
         def actions
-          @actions ||= begin
-            policy_methods = @policy.public_methods - Object.instance_methods
-            policy_methods.grep(/\?$/).sort.map { |policy_method| policy_method.to_s.delete_suffix('?').to_sym }
+          @actions ||= policy_public_methods.grep(/\?$/).sort.map do |policy_method|
+            policy_method.to_s.delete_suffix('?').to_sym
           end
         end
 
+        # Returns an array of all permitted actions defined in the policy class.
+        #
+        # @return [Array<Symbol>] An array of all permitted actions defined in the policy class.
         def permitted_actions
-          @permitted_actions ||= actions.select { |action| policy.public_send("#{action}?") }
+          @permitted_actions ||= actions.select { |action| policy.public_send(:"#{action}?") }
         end
 
+        # Returns an array of all forbidden actions defined in the policy class.
+        #
+        # @return [Array<Symbol>] An array of all forbidden actions defined in the policy class.
         def forbidden_actions
-          actions - permitted_actions
+          @forbidden_actions ||= actions - permitted_actions
+        end
+
+        private
+
+        def policy_public_methods
+          @policy_public_methods ||= policy.public_methods - Object.instance_methods
+        end
+
+        def user_alias
+          @user_alias ||= Pundit::Matchers.configuration.user_alias(policy)
+        end
+
+        def check_user_alias!
+          return if policy.respond_to?(user_alias)
+
+          raise ArgumentError, format(USER_NOT_IMPLEMENTED_ERROR, policy: self, user_alias: user_alias)
         end
       end
     end
   end
 end