require 'set'
module ActiveRecord
# :stopdoc:
module ConnectionAdapters
# An abstract definition of a column in a table.
class Column
FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE', 'off', 'OFF'].to_set
module Format
ISO_DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
end
attr_reader :name, :cast_type, :null, :sql_type, :default, :default_function
delegate :precision, :scale, :limit, :type, to: :cast_type
# Instantiates a new column in the table.
#
# +name+ is the column's name, such as supplier_id in supplier_id int(11).
# +default+ is the type-casted default value, such as +new+ in sales_stage varchar(20) default 'new'.
# +cast_type+ is the object used for type casting and type information.
# +sql_type+ is used to extract the column's length, if necessary. For example +60+ in
# company_name varchar(60).
# It will be mapped to one of the standard Rails SQL types in the type attribute.
# +null+ determines if this column allows +NULL+ values.
def initialize(name, default, cast_type, sql_type = nil, null = true, default_function = nil)
@name = name
@cast_type = cast_type
@sql_type = sql_type
@null = null
@default = default
@default_function = default_function
end
def has_default?
!default.nil?
end
# Returns the human name of the column name.
#
# ===== Examples
# Column.new('sales_stage', ...).human_name # => 'Sales stage'
def human_name
Base.human_attribute_name(@name)
end
def with_type(type)
dup.tap do |clone|
clone.instance_variable_set('@cast_type', type)
end
end
def ==(other)
other.name == name &&
other.default == default &&
other.cast_type == cast_type &&
other.sql_type == sql_type &&
other.null == null &&
other.default_function == default_function
end
alias :eql? :==
def hash
attributes_for_hash.hash
end
private
def attributes_for_hash
[self.class, name, default, cast_type, sql_type, null, default_function]
end
end
class NullColumn < Column
def initialize(name)
super name, nil, Type::Value.new
end
end
end
# :startdoc:
end