auxiliary_statement.rb in torque-postgresql-2.4.0

- old
+ new

@@ -1,42 +1,46 @@
 # frozen_string_literal: true
 
 require_relative 'auxiliary_statement/settings'
+require_relative 'auxiliary_statement/recursive'
 
 module Torque
   module PostgreSQL
     class AuxiliaryStatement
       TABLE_COLUMN_AS_STRING = /\A(?:"?(\w+)"?\.)?"?(\w+)"?\z/.freeze
 
       class << self
-        attr_reader :config
+        attr_reader :config, :table_name
 
         # Find or create the class that will handle statement
         def lookup(name, base)
           const = name.to_s.camelize << '_' << self.name.demodulize
           return base.const_get(const, false) if base.const_defined?(const, false)
-          base.const_set(const, Class.new(AuxiliaryStatement))
+
+          base.const_set(const, Class.new(self)).tap do |klass|
+            klass.instance_variable_set(:@table_name, name.to_s)
+          end
         end
 
         # Create a new instance of an auxiliary statement
-        def instantiate(statement, base, options = nil)
+        def instantiate(statement, base, **options)
           klass = while base < ActiveRecord::Base
             list = base.auxiliary_statements_list
             break list[statement] if list.present? && list.key?(statement)
 
             base = base.superclass
           end
 
-          return klass.new(options) unless klass.nil?
+          return klass.new(**options) unless klass.nil?
           raise ArgumentError, <<-MSG.squish
             There's no '#{statement}' auxiliary statement defined for #{base.class.name}.
           MSG
         end
 
         # Fast access to statement build
-        def build(statement, base, options = nil, bound_attributes = [], join_sources = [])
-          klass = instantiate(statement, base, options)
+        def build(statement, base, bound_attributes = [], join_sources = [], **options)
+          klass = instantiate(statement, base, **options)
           result = klass.build(base)
 
           bound_attributes.concat(klass.bound_attributes)
           join_sources.concat(klass.join_sources)
           result
@@ -54,11 +58,11 @@
         end
 
         # A way to create auxiliary statements outside of models configurations,
         # being able to use on extensions
         def create(table_or_settings, &block)
-          klass = Class.new(AuxiliaryStatement)
+          klass = Class.new(self)
 
           if block_given?
             klass.instance_variable_set(:@table_name, table_or_settings)
             klass.configurator(block)
           elsif relation_query?(table_or_settings)
@@ -87,41 +91,36 @@
 
         # Run a configuration block or get the static configuration
         def configure(base, instance)
           return @config unless @config.respond_to?(:call)
 
-          settings = Settings.new(base, instance)
+          recursive = self < AuxiliaryStatement::Recursive
+          settings = Settings.new(base, instance, recursive)
           settings.instance_exec(settings, &@config)
           settings
         end
 
         # Get the arel version of the statement table
         def table
           @table ||= ::Arel::Table.new(table_name)
         end
-
-        # Get the name of the table of the configurated statement
-        def table_name
-          @table_name ||= self.name.demodulize.split('_').first.underscore
-        end
       end
 
       delegate :config, :table, :table_name, :relation, :configure, :relation_query?,
         to: :class
 
       attr_reader :bound_attributes, :join_sources
 
       # Start a new auxiliary statement giving extra options
-      def initialize(*args)
-        options = args.extract_options!
+      def initialize(*, **options)
         args_key = Torque::PostgreSQL.config.auxiliary_statement.send_arguments_key
 
         @join = options.fetch(:join, {})
         @args = options.fetch(args_key, {})
         @where = options.fetch(:where, {})
         @select = options.fetch(:select, {})
-        @join_type = options.fetch(:join_type, nil)
+        @join_type = options[:join_type]
 
         @bound_attributes = []
         @join_sources = []
       end
 
@@ -129,48 +128,46 @@
       def build(base)
         @bound_attributes.clear
         @join_sources.clear
 
         # Prepare all the data for the statement
-        prepare(base)
+        prepare(base, configure(base, self))
 
         # Add the join condition to the list
         @join_sources << build_join(base)
 
         # Return the statement with its dependencies
         [@dependencies, ::Arel::Nodes::As.new(table, build_query(base))]
       end
 
       private
         # Setup the statement using the class configuration
-        def prepare(base)
-          settings = configure(base, self)
+        def prepare(base, settings)
           requires = Array.wrap(settings.requires).flatten.compact
           @dependencies = ensure_dependencies(requires, base).flatten.compact
 
           @join_type ||= settings.join_type || :inner
           @query = settings.query
 
           # Call a proc to get the real query
-          if @query.methods.include?(:call)
+          if @query.respond_to?(:call)
             call_args = @query.try(:arity) === 0 ? [] : [OpenStruct.new(@args)]
             @query = @query.call(*call_args)
             @args = []
           end
 
-          # Manually set the query table when it's not an relation query
-          @query_table = settings.query_table unless relation_query?(@query)
+          # Merge select attributes provided on the instance creation
           @select = settings.attributes.merge(@select) if settings.attributes.present?
 
           # Merge join settings
           if settings.join.present?
             @join = settings.join.merge(@join)
           elsif settings.through.present?
             @association = settings.through.to_s
           elsif relation_query?(@query)
             @association = base.reflections.find do |name, reflection|
-              break name if @query.klass.eql? reflection.klass
+              break name if @query.klass.eql?(reflection.klass)
             end
           end
         end
 
         # Build the string or arel query
@@ -232,19 +229,10 @@
           raise ArgumentError, <<-MSG.squish if conditions.children.empty?
             You must provide the join columns when using '#{@query.class.name}'
             as a query object on #{self.class.name}.
           MSG
 
-          # Expose join columns
-          if relation_query?(@query)
-            query_table = @query.arel_table
-            conditions.children.each do |item|
-              @query.select_values += [query_table[item.left.name]] \
-                if item.left.relation.eql?(table)
-            end
-          end
-
           # Build the join based on the join type
           arel_join.new(table, table.create_on(conditions))
         end
 
         # Get the class of the join on arel
@@ -261,32 +249,43 @@
           end
         end
 
         # Mount the list of selected attributes
         def expose_columns(base, query_table = nil)
-          # Add select columns to the query and get exposed columns
-          @select.map do |left, right|
-            base.select_extra_values += [table[right.to_s]]
-            project(left, query_table).as(right.to_s) if query_table
+          # Add the columns necessary for the join
+          list = @join_sources.each_with_object(@select) do |join, hash|
+            join.right.expr.children.each do |item|
+              hash[item.left.name] = nil if item.left.relation.eql?(table)
+            end
           end
+
+          # Add select columns to the query and get exposed columns
+          list.map do |left, right|
+            base.select_extra_values += [table[right.to_s]] unless right.nil?
+            next unless query_table
+
+            col = project(left, query_table)
+            right.nil? ? col : col.as(right.to_s)
+          end.compact
         end
 
         # Ensure that all the dependencies are loaded in the base relation
         def ensure_dependencies(list, base)
           with_options = list.extract_options!.to_a
-          (list + with_options).map do |dependent, options|
-            dependent_klass = base.model.auxiliary_statements_list[dependent]
+          (list + with_options).map do |name, options|
+            dependent_klass = base.model.auxiliary_statements_list[name]
 
             raise ArgumentError, <<-MSG.squish if dependent_klass.nil?
-              The '#{dependent}' auxiliary statement dependency can't found on
+              The '#{name}' auxiliary statement dependency can't found on
               #{self.class.name}.
             MSG
 
             next if base.auxiliary_statements_values.any? do |cte|
               cte.is_a?(dependent_klass)
             end
 
-            AuxiliaryStatement.build(dependent, base, options, bound_attributes, join_sources)
+            options ||= {}
+            AuxiliaryStatement.build(name, base, bound_attributes, join_sources, **options)
           end
         end
 
         # Project a column on a given table, or use the column table
         def project(column, arel_table = nil)