webrat/lib/merb_support/indifferent_access.rb

139 lines
3.1 KiB
Ruby

# This class has dubious semantics and we only have it so that
# people can write params[:key] instead of params['key']
# and they get the same value for both keys.
class HashWithIndifferentAccess < Hash
def initialize(constructor = {})
if constructor.is_a?(Hash)
super()
update(constructor)
else
super(constructor)
end
end
def default(key = nil)
if key.is_a?(Symbol) && include?(key = key.to_s)
self[key]
else
super
end
end
alias_method :regular_writer, :[]= unless method_defined?(:regular_writer)
alias_method :regular_update, :update unless method_defined?(:regular_update)
#
# Assigns a new value to the hash.
#
# Example:
#
# hash = HashWithIndifferentAccess.new
# hash[:key] = "value"
#
def []=(key, value)
regular_writer(convert_key(key), convert_value(value))
end
#
# Updates the instantized hash with values from the second.
#
# Example:
#
# >> hash_1 = HashWithIndifferentAccess.new
# => {}
#
# >> hash_1[:key] = "value"
# => "value"
#
# >> hash_2 = HashWithIndifferentAccess.new
# => {}
#
# >> hash_2[:key] = "New Value!"
# => "New Value!"
#
# >> hash_1.update(hash_2)
# => {"key"=>"New Value!"}
#
def update(other_hash)
other_hash.each_pair { |key, value| regular_writer(convert_key(key), convert_value(value)) }
self
end
alias_method :merge!, :update
# Checks the hash for a key matching the argument passed in
def key?(key)
super(convert_key(key))
end
alias_method :include?, :key?
alias_method :has_key?, :key?
alias_method :member?, :key?
# Fetches the value for the specified key, same as doing hash[key]
def fetch(key, *extras)
super(convert_key(key), *extras)
end
# Returns an array of the values at the specified indicies.
def values_at(*indices)
indices.collect {|key| self[convert_key(key)]}
end
# Returns an exact copy of the hash.
def dup
HashWithIndifferentAccess.new(self)
end
# Merges the instantized and the specified hashes together, giving precedence to the values from the second hash
# Does not overwrite the existing hash.
def merge(hash)
self.dup.update(hash)
end
# Removes a specified key from the hash.
def delete(key)
super(convert_key(key))
end
def stringify_keys!; self end
def symbolize_keys!; self end
def to_options!; self end
# Convert to a Hash with String keys.
def to_hash
Hash.new(default).merge(self)
end
protected
def convert_key(key)
key.kind_of?(Symbol) ? key.to_s : key
end
def convert_value(value)
case value
when Hash
value.with_indifferent_access
when Array
value.collect { |e| e.is_a?(Hash) ? e.with_indifferent_access : e }
else
value
end
end
end
module ActiveSupport #:nodoc:
module CoreExtensions #:nodoc:
module Hash #:nodoc:
module IndifferentAccess #:nodoc:
def with_indifferent_access
hash = HashWithIndifferentAccess.new(self)
hash.default = self.default
hash
end
end
end
end
end