I think I have found a bug in marshaling in version “ruby 1.8.1
(2003-10-31) [powerpc-darwin]”. It’s difficult to describe in
words, but I have a failing test.
It seems to require a subclass of Array that adds an instance
variable, an object of that class, and another object that refers to
the first object. Change any of those facts, and you do not get this
failure upon loading the marshaled data:
- Error:
test_marshaling(SessionTests):
EOFError: End of file reached
/Users/marick/src/timeclock/timeclock/server/marshal-test.rb:32:in
load' /Users/marick/src/timeclock/timeclock/server/marshal-test.rb:32:inload’
/Users/marick/src/timeclock/timeclock/server/marshal-test.rb:31:in
open' /Users/marick/src/timeclock/timeclock/server/marshal-test.rb:31:inload’
/Users/marick/src/timeclock/timeclock/server/marshal-test.rb:52:in
`test_marshaling’
Here is the Test::Unit test. I hope it’s reasonably clear. It’s a
drastically stripped-down version of the original code+test.
Is this a true bug?
========== snip ================
require ‘pp’
Inherit from some user-defined class, and the test passes
class RecordList < Array
def initialize
super
@next_record_id = 0 # Delete this line, and the test passes.
end
end
class ActiveJobManager
def initialize(all_records)
@all_records = all_records # Delete this line, and the test passes
end
end
class Session
def initialize(user)
@user = user
@records = RecordList.new
# Use the following instead of the above, and the test passes.
# @records = []
@active_job_manager = ActiveJobManager.new(@records)
# Use the following instead of the above, and the test passes.
# @active_job_manager = ActiveJobManager.new([])
end
def load
@records, @active_job_manager = File.open(@user, “r”) { | f |
Marshal.load(f)
}
end
def save
File.open(@user, “w”) { | f |
Marshal.dump([@records, @active_job_manager], f)
}
end
end
class SessionTests < Test::Unit::TestCase
TEST_USER = “marshal-test-data”
def test_marshaling
File.delete(TEST_USER) if FileTest.exists?(TEST_USER)
@session = Session.new(TEST_USER)
@session.save
pp @session.load
end
end
···
Brian Marick
Consulting, training, contracting, and research
Focused on the intersection of testing, programming, and design
marick@testing.com, marick@visibleworkings.com
www.testing.com, www.visibleworkings.com