class ActiveRecord::Associations::JoinDependency::Aliases

:nodoc:

def column_alias(node, column) 

def column_alias(node, column)
  @alias_cache[node][column]
end

def column_aliases(node)

An array of [column_name, alias] pairs for the table 
def column_aliases(node)
  @name_and_alias_cache[node]
end

def columns 

def columns
  @tables.flat_map { |t| t.column_aliases }
end

def initialize(tables)

:nodoc: 
def initialize(tables)
  @tables = tables
  @alias_cache = tables.each_with_object({}) { |table,h|
    h[table.node] = table.columns.each_with_object({}) { |column,i|
      i[column.name] = column.alias
    }
  }
  @name_and_alias_cache = tables.each_with_object({}) { |table,h|
    h[table.node] = table.columns.map { |column|
      [column.name, column.alias]
    }
  }
end