Class: Jekyll::Drops::Drop

Inherits:
Liquid::Drop
  • Object
show all
Includes:
Enumerable
Defined in:
lib/jekyll/drops/drop.rb

Constant Summary collapse

NON_CONTENT_METHODS = 
[:fallback_data, :collapse_document].freeze

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(obj) ⇒ Drop

Create a new Drop

obj - the Jekyll Site, Collection, or Document required by the drop.

Returns nothing



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# File 'lib/jekyll/drops/drop.rb', line 35

def initialize(obj)
  @obj = obj
  @mutations = {} # only if mutable: true
end

Class Method Details

.mutable(is_mutable = nil) ⇒ Object

Get or set whether the drop class is mutable. Mutability determines whether or not pre-defined fields may be overwritten.

is_mutable - Boolean set mutability of the class (default: nil)

Returns the mutability of the class



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# File 'lib/jekyll/drops/drop.rb', line 17

def self.mutable(is_mutable = nil)
  @is_mutable = if is_mutable
                  is_mutable
                else
                  false
                end
end

.mutable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/jekyll/drops/drop.rb', line 25

def self.mutable?
  @is_mutable
end

Instance Method Details

#[](key) ⇒ Object Also known as: invoke_drop

Access a method in the Drop or a field in the underlying hash data. If mutable, checks the mutations first. Then checks the methods, and finally check the underlying hash (e.g. document front matter) if all the previous places didn’t match.

key - the string key whose value to fetch

Returns the value for the given key, or nil if none exists



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# File 'lib/jekyll/drops/drop.rb', line 48

def [](key)
  if self.class.mutable? && @mutations.key?(key)
    @mutations[key]
  elsif self.class.invokable? key
    public_send key
  else
    fallback_data[key]
  end
end

#[]=(key, val) ⇒ Object

Set a field in the Drop. If mutable, sets in the mutations and returns. If not mutable, checks first if it’s trying to override a Drop method and raises a DropMutationException if so. If not mutable and the key is not a method on the Drop, then it sets the key to the value in the underlying hash (e.g. document front matter)

key - the String key whose value to set val - the Object to set the key’s value to

Returns the value the key was set to unless the Drop is not mutable and the key matches a method in which case it raises a DropMutationException.



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# File 'lib/jekyll/drops/drop.rb', line 72

def []=(key, val)
  if respond_to?("#{key}=")
    public_send("#{key}=", val)
  elsif respond_to?(key.to_s)
    if self.class.mutable?
      @mutations[key] = val
    else
      raise Errors::DropMutationException, "Key #{key} cannot be set in the drop."
    end
  else
    fallback_data[key] = val
  end
end

#content_methods ⇒ Object

Generates a list of strings which correspond to content getter methods.

Returns an Array of strings which represent method-specific keys.



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# File 'lib/jekyll/drops/drop.rb', line 90

def content_methods
  @content_methods ||= (
    self.class.instance_methods \
      - Jekyll::Drops::Drop.instance_methods \
      - NON_CONTENT_METHODS
  ).map(&:to_s).reject do |method|
    method.end_with?("=")
  end
end

#each ⇒ Object 



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# File 'lib/jekyll/drops/drop.rb', line 169

def each
  each_key.each do |key|
    yield key, self[key]
  end
end

#each_key(&block) ⇒ Object

Collects all the keys and passes each to the block in turn.

block - a block which accepts one argument, the key

Returns nothing.



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# File 'lib/jekyll/drops/drop.rb', line 165

def each_key(&block)
  keys.each(&block)
end

#fetch(key, default = nil, &block) ⇒ Object

Imitate Hash.fetch method in Drop

Returns value if key is present in Drop, otherwise returns default value KeyError is raised if key is not present and no default value given

Raises:

  • (KeyError) 


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# File 'lib/jekyll/drops/drop.rb', line 204

def fetch(key, default = nil, &block)
  return self[key] if key?(key)
  raise KeyError, %(key not found: "#{key}") if default.nil? && block.nil?
  return yield(key) unless block.nil?
  return default unless default.nil?
end

#hash_for_json ⇒ Object

Generate a Hash for use in generating JSON. This is useful if fields need to be cleared before the JSON can generate.

Returns a Hash ready for JSON generation.



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# File 'lib/jekyll/drops/drop.rb', line 147

def hash_for_json(*)
  to_h
end

#inspect ⇒ Object

Inspect the drop’s keys and values through a JSON representation of its keys and values.

Returns a pretty generation of the hash representation of the Drop.



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# File 'lib/jekyll/drops/drop.rb', line 139

def inspect
  JSON.pretty_generate to_h
end

#key?(key) ⇒ Boolean

Check if key exists in Drop

key - the string key whose value to fetch

Returns true if the given key is present

Returns:

  • (Boolean) 


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# File 'lib/jekyll/drops/drop.rb', line 105

def key?(key)
  return false if key.nil?
  return true if self.class.mutable? && @mutations.key?(key)
  respond_to?(key) || fallback_data.key?(key)
end

#keys ⇒ Object

Generates a list of keys with user content as their values. This gathers up the Drop methods and keys of the mutations and underlying data hashes and performs a set union to ensure a list of unique keys for the Drop.

Returns an Array of unique keys for content for the Drop.



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# File 'lib/jekyll/drops/drop.rb', line 117

def keys
  (content_methods |
    @mutations.keys |
    fallback_data.keys).flatten
end

#merge(other, &block) ⇒ Object 



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# File 'lib/jekyll/drops/drop.rb', line 175

def merge(other, &block)
  self.dup.tap do |me|
    if block.nil?
      me.merge!(other)
    else
      me.merge!(other, block)
    end
  end
end

#merge!(other) ⇒ Object 



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# File 'lib/jekyll/drops/drop.rb', line 185

def merge!(other)
  other.each_key do |key|
    if block_given?
      self[key] = yield key, self[key], other[key]
    else
      if Utils.mergable?(self[key]) && Utils.mergable?(other[key])
        self[key] = Utils.deep_merge_hashes(self[key], other[key])
        next
      end

      self[key] = other[key] unless other[key].nil?
    end
  end
end

#to_h ⇒ Object Also known as: to_hash

Generate a Hash representation of the Drop by resolving each key’s value. It includes Drop methods, mutations, and the underlying object’s data. See the documentation for Drop#keys for more.

Returns a Hash with all the keys and values resolved.



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# File 'lib/jekyll/drops/drop.rb', line 128

def to_h
  keys.each_with_object({}) do |(key, _), result|
    result[key] = self[key]
  end
end

#to_json(state = nil) ⇒ Object

Generate a JSON representation of the Drop.

state - the JSON::State object which determines the state of current processing.

Returns a JSON representation of the Drop in a String.



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# File 'lib/jekyll/drops/drop.rb', line 156

def to_json(state = nil)
  JSON.generate(hash_for_json(state), state)
end