class Hash

Extracted from rails raw.githubusercontent.com/rails/rails/master/activesupport/lib/active_support/core_ext/hash/keys.rb

Public Instance Methods

assert_valid_keys(*valid_keys) click to toggle source

Validates all keys in a hash match *valid_keys, raising ArgumentError on a mismatch.

Note that keys are treated differently than HashWithIndifferentAccess, meaning that string and symbol keys will not match.

{ name: 'Rob', years: '28' }.assert_valid_keys(:name, :age) # => raises "ArgumentError: Unknown key: :years. Valid keys are: :name, :age"
{ name: 'Rob', age: '28' }.assert_valid_keys('name', 'age') # => raises "ArgumentError: Unknown key: :name. Valid keys are: 'name', 'age'"
{ name: 'Rob', age: '28' }.assert_valid_keys(:name, :age)   # => passes, raises nothing
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 78
def assert_valid_keys(*valid_keys)
  valid_keys.flatten!
  each_key do |k|
    unless valid_keys.include?(k)
      raise ArgumentError.new("Unknown key: #{k.inspect}. Valid keys are: #{valid_keys.map(&:inspect).join(', ')}")
    end
  end
end
deep_stringify_keys() click to toggle source

Returns a new hash with all keys converted to strings. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { person: { name: 'Rob', age: '28' } }

hash.deep_stringify_keys
# => {"person"=>{"name"=>"Rob", "age"=>"28"}}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 114
def deep_stringify_keys
  deep_transform_keys(&:to_s)
end
deep_stringify_keys!() click to toggle source

Destructively converts all keys to strings. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 121
def deep_stringify_keys!
  deep_transform_keys!(&:to_s)
end
deep_symbolize_keys() click to toggle source

Returns a new hash with all keys converted to symbols, as long as they respond to to_sym. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { 'person' => { 'name' => 'Rob', 'age' => '28' } }

hash.deep_symbolize_keys
# => {:person=>{:name=>"Rob", :age=>"28"}}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 133
def deep_symbolize_keys
  deep_transform_keys { |key| key.to_sym rescue key }
end
deep_symbolize_keys!() click to toggle source

Destructively converts all keys to symbols, as long as they respond to to_sym. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 140
def deep_symbolize_keys!
  deep_transform_keys! { |key| key.to_sym rescue key }
end
deep_transform_keys(&block) click to toggle source

Returns a new hash with all keys converted by the block operation. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { person: { name: 'Rob', age: '28' } }

hash.deep_transform_keys{ |key| key.to_s.upcase }
# => {"PERSON"=>{"NAME"=>"Rob", "AGE"=>"28"}}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 95
def deep_transform_keys(&block)
  _deep_transform_keys_in_object(self, &block)
end
deep_transform_keys!(&block) click to toggle source

Destructively converts all keys by using the block operation. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 102
def deep_transform_keys!(&block)
  _deep_transform_keys_in_object!(self, &block)
end
stringify_keys() click to toggle source

Returns a new hash with all keys converted to strings.

hash = { name: 'Rob', age: '28' }

hash.stringify_keys
# => {"name"=>"Rob", "age"=>"28"}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 40
def stringify_keys
  transform_keys(&:to_s)
end
stringify_keys!() click to toggle source

Destructively converts all keys to strings. Same as stringify_keys, but modifies self.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 46
def stringify_keys!
  transform_keys!(&:to_s)
end
symbolize_keys() click to toggle source

Returns a new hash with all keys converted to symbols, as long as they respond to to_sym.

hash = { 'name' => 'Rob', 'age' => '28' }

hash.symbolize_keys
# => {:name=>"Rob", :age=>"28"}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 57
def symbolize_keys
  transform_keys { |key| key.to_sym rescue key }
end
Also aliased as: to_options
symbolize_keys!() click to toggle source

Destructively converts all keys to symbols, as long as they respond to to_sym. Same as symbolize_keys, but modifies self.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 64
def symbolize_keys!
  transform_keys! { |key| key.to_sym rescue key }
end
Also aliased as: to_options!
to_options()
Alias for: symbolize_keys
to_options!()
Alias for: symbolize_keys!
transform_keys() { |key| ... } click to toggle source

Returns a new hash with all keys converted using the block operation.

hash = { name: 'Rob', age: '28' }

hash.transform_keys { |key| key.to_s.upcase } # => {"NAME"=>"Rob", "AGE"=>"28"}

If you do not provide a block, it will return an Enumerator for chaining with other methods:

hash.transform_keys.with_index { |k, i| [k, i].join } # => {"name0"=>"Rob", "age1"=>"28"}
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 15
def transform_keys
  return enum_for(:transform_keys) { size } unless block_given?
  result = {}
  each_key do |key|
    result[yield(key)] = self[key]
  end
  result
end
transform_keys!() { |key| ... } click to toggle source

Destructively converts all keys using the block operations. Same as transform_keys but modifies self.

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 26
def transform_keys!
  return enum_for(:transform_keys!) { size } unless block_given?
  keys.each do |key|
    self[yield(key)] = delete(key)
  end
  self
end

Private Instance Methods

_deep_transform_keys_in_object(object) { |key| ... } click to toggle source

support methods for deep transforming nested hashes and arrays

# File lib/liquid_markdown/core_ext/hash/keys.rb, line 146
def _deep_transform_keys_in_object(object, &block)
  case object
    when Hash
      object.each_with_object({}) do |(key, value), result|
        result[yield(key)] = _deep_transform_keys_in_object(value, &block)
      end
    when Array
      object.map { |e| _deep_transform_keys_in_object(e, &block) }
    else
      object
  end
end
_deep_transform_keys_in_object!(object) { |key| ... } click to toggle source
# File lib/liquid_markdown/core_ext/hash/keys.rb, line 159
def _deep_transform_keys_in_object!(object, &block)
  case object
    when Hash
      object.keys.each do |key|
        value = object.delete(key)
        object[yield(key)] = _deep_transform_keys_in_object!(value, &block)
      end
      object
    when Array
      object.map! { |e| _deep_transform_keys_in_object!(e, &block) }
    else
      object
  end
end