1 files changed, 111 insertions, 0 deletions
diff --git a/activerecord/lib/arel/table.rb b/activerecord/lib/arel/table.rb
new file mode 100644
index 0000000000..686fcdf962
--- /dev/null
+++ b/activerecord/lib/arel/table.rb
@@ -0,0 +1,111 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+  class Table
+    include Arel::Crud
+    include Arel::FactoryMethods
+
+    @engine = nil
+    class << self; attr_accessor :engine; end
+
+    attr_accessor :name, :table_alias
+
+    # TableAlias and Table both have a #table_name which is the name of the underlying table
+    alias :table_name :name
+
+    def initialize(name, as: nil, type_caster: nil)
+      @name = name.to_s
+      @type_caster = type_caster
+
+      # Sometime AR sends an :as parameter to table, to let the table know
+      # that it is an Alias.  We may want to override new, and return a
+      # TableAlias node?
+      if as.to_s == @name
+        as = nil
+      end
+      @table_alias = as
+    end
+
+    def alias(name = "#{self.name}_2")
+      Nodes::TableAlias.new(self, name)
+    end
+
+    def from
+      SelectManager.new(self)
+    end
+
+    def join(relation, klass = Nodes::InnerJoin)
+      return from unless relation
+
+      case relation
+      when String, Nodes::SqlLiteral
+        raise EmptyJoinError if relation.empty?
+        klass = Nodes::StringJoin
+      end
+
+      from.join(relation, klass)
+    end
+
+    def outer_join(relation)
+      join(relation, Nodes::OuterJoin)
+    end
+
+    def group(*columns)
+      from.group(*columns)
+    end
+
+    def order(*expr)
+      from.order(*expr)
+    end
+
+    def where(condition)
+      from.where condition
+    end
+
+    def project(*things)
+      from.project(*things)
+    end
+
+    def take(amount)
+      from.take amount
+    end
+
+    def skip(amount)
+      from.skip amount
+    end
+
+    def having(expr)
+      from.having expr
+    end
+
+    def [](name)
+      ::Arel::Attribute.new self, name
+    end
+
+    def hash
+      # Perf note: aliases and table alias is excluded from the hash
+      #  aliases can have a loop back to this table breaking hashes in parent
+      #  relations, for the vast majority of cases @name is unique to a query
+      @name.hash
+    end
+
+    def eql?(other)
+      self.class == other.class &&
+        self.name == other.name &&
+        self.table_alias == other.table_alias
+    end
+    alias :== :eql?
+
+    def type_cast_for_database(attribute_name, value)
+      type_caster.type_cast_for_database(attribute_name, value)
+    end
+
+    def able_to_type_cast?
+      !type_caster.nil?
+    end
+
+    protected
+
+      attr_reader :type_caster
+  end
+end