jekyll/lib/jekyll/plugin.rb

78 lines
2.0 KiB
Ruby

module Jekyll
class Plugin
PRIORITIES = { :lowest => -100,
:low => -10,
:normal => 0,
:high => 10,
:highest => 100 }
# Fetch all the subclasses of this class and its subclasses' subclasses.
#
# Returns an array of descendant classes.
def self.descendants
descendants = []
ObjectSpace.each_object(singleton_class) do |k|
descendants.unshift k unless k == self
end
descendants
end
# Get or set the priority of this plugin. When called without an
# argument it returns the priority. When an argument is given, it will
# set the priority.
#
# priority - The Symbol priority (default: nil). Valid options are:
# :lowest, :low, :normal, :high, :highest
#
# Returns the Symbol priority.
def self.priority(priority = nil)
@priority ||= nil
if priority && PRIORITIES.key?(priority)
@priority = priority
end
@priority || :normal
end
# Get or set the safety of this plugin. When called without an argument
# it returns the safety. When an argument is given, it will set the
# safety.
#
# safe - The Boolean safety (default: nil).
#
# Returns the safety Boolean.
def self.safe(safe = nil)
if safe
@safe = safe
end
@safe || false
end
# Spaceship is priority [higher -> lower]
#
# other - The class to be compared.
#
# Returns -1, 0, 1.
def self.<=>(other)
PRIORITIES[other.priority] <=> PRIORITIES[self.priority]
end
# Spaceship is priority [higher -> lower]
#
# other - The class to be compared.
#
# Returns -1, 0, 1.
def <=>(other)
self.class <=> other.class
end
# Initialize a new plugin. This should be overridden by the subclass.
#
# config - The Hash of configuration options.
#
# Returns a new instance.
def initialize(config = {})
# no-op for default
end
end
end