free_mutant/lib/mutant/zombifier.rb

127 lines
2.5 KiB
Ruby

module Mutant
# Zombifier namespace
class Zombifier
include Anima.new(
:includes,
:namespace,
:load_path,
:kernel,
:require_highjack,
:root_require,
:pathname
)
include AST::Sexp
LoadError = Class.new(::LoadError)
# Initialize object
#
# @param [Symbol] namespace
#
# @return [undefined]
#
# @api private
def initialize(*)
super
@includes = %r{\A#{Regexp.union(includes)}(?:/.*)?\z}
@zombified = Set.new
end
# Call zombifier
#
# @return [self]
#
# @api private
def self.call(*args)
new(*args).__send__(:call)
self
end
private
# Run zombifier
#
# @return [undefined]
#
# @api private
def call
@original = require_highjack.call(method(:require))
require(root_require)
end
# Test if logical name is subjected to zombification
#
# @param [String]
#
# @api private
def include?(logical_name)
!@zombified.include?(logical_name) && @includes =~ logical_name
end
# Require file in zombie namespace
#
# @param [#to_s] logical_name
#
# @return [undefined]
#
# @api private
def require(logical_name)
logical_name = logical_name.to_s
@original.call(logical_name)
return unless include?(logical_name)
@zombified << logical_name
zombify(find(logical_name))
end
# Find file by logical path
#
# @param [String] logical_name
#
# @return [File]
#
# @raise [LoadError]
# otherwise
#
# @api private
def find(logical_name)
file_name = "#{logical_name}.rb"
load_path.each do |path|
path = pathname.new(path).join(file_name)
return path if path.file?
end
fail LoadError, "Cannot find file #{file_name.inspect} in load path"
end
# Zombify contents of file
#
# Probably the 2nd valid use of eval ever. (First one is inserting mutants!).
#
# @param [Pathname] source_path
#
# @return [undefined]
#
# @api private
def zombify(source_path)
kernel.eval(
Unparser.unparse(namespaced_node(source_path)),
TOPLEVEL_BINDING,
source_path.to_s
)
end
# Namespaced root node
#
# @param [Pathname] source_path
#
# @return [Parser::AST::Node]
#
# @api private
def namespaced_node(source_path)
s(:module, s(:const, nil, namespace), Parser::CurrentRuby.parse(source_path.read))
end
end # Zombifier
end # Mutant