Class: Jekyll::PathManager

Inherits:
Object
  • Object
show all
Defined in:
lib/jekyll/path_manager.rb

Overview

A singleton class that caches frozen instances of path strings returned from its methods.

NOTE:

This class exists because `File.join` allocates an Array and returns a new String on every
call using **the same arguments**. Caching the result means reduced memory usage.
However, the caches are never flushed so that they can be used even when a site is
regenerating. The results are frozen to deter mutation of the cached string.

Therefore, employ this class only for situations where caching the result is necessary
for performance reasons.

Class Method Summary collapse

Class Method Details

.join(base, item) ⇒ Object

Wraps ‘File.join` to cache the frozen result. Reassigns `nil`, empty strings and empty arrays to a frozen empty string beforehand.

Returns a frozen string.



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# File 'lib/jekyll/path_manager.rb', line 24

def join(base, item)
  base = "" if base.nil? || base.empty?
  item = "" if item.nil? || item.empty?
  @join ||= {}
  @join[base] ||= {}
  @join[base][item] ||= File.join(base, item).freeze
end

.sanitized_path(base_directory, questionable_path) ⇒ Object

Ensures the questionable path is prefixed with the base directory and prepends the questionable path with the base directory if false.

Returns a frozen string.



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# File 'lib/jekyll/path_manager.rb', line 36

def sanitized_path(base_directory, questionable_path)
  @sanitized_path ||= {}
  @sanitized_path[base_directory] ||= {}
  @sanitized_path[base_directory][questionable_path] ||= if questionable_path.nil?
                                                           base_directory.freeze
                                                         else
                                                           sanitize_and_join(
                                                             base_directory, questionable_path
                                                           ).freeze
                                                         end
end