Initialize the monitor for new subarrays on Rubinius #665
Conversation
Rubinius uses the public methods `new_range` and `new_reserved` to
create new sub-arrays in methods like `Array#slice`, `Array#[](range)`
or similar.
Here, Rubinius does not call `Array.allocate` to create the new object
resulting in the monitor not being initialized which then causes errors
like
NoMethodError: undefined method `synchronize' on nil:NilClass.
when calling any methods of the new sub-array. By overwriting the two
methods and explicitly initializing the monitor there, we can ensure
that the monitor is always initialized correctly.
|
For reference, It is used in e.g. |
| @@ -14,5 +14,15 @@ module Concurrent | |||
| end | |||
| end.map(&:join) | |||
| end | |||
|
|
|||
| describe '#slice' do | |||
| # This is mostly relevant on Rubinius and Truffle | |||
There was a problem hiding this comment.
FWIW TruffleRuby tries to avoid extra public methods, so new_range/new_reserved are not defined on Array in TruffleRuby.
Arguably, this is a Rubinius bug to expose internal methods as public.
There was a problem hiding this comment.
The problem is not so much that this method is public rather than that they are "special" to Rubinius in that they create objects without calling allocate. They would still have to be overwritten by concurrent-ruby if they were private, although it would have to be done slightly different...
As for the comment itself, I have not tested this on Truffle nor have I specifically checked their implementation to be honest. The comment might thus be not 100% exact in this regard. However, since the monitor is only used on Rubinius and Truffle at all, the test still applies to this locking variant used here.
This pull request should fix #559.
Rubinius uses the public methods
new_rangeandnew_reservedtocreate new sub-arrays in methods like
Array#slice,Array#[](range)or similar.
Here, Rubinius does not call
Array.allocateto create the new objectresulting in the monitor not being initialized which then causes errors
like
when calling any methods of the new sub-array. By overwriting the two
methods and explicitly initializing the monitor there, we can ensure
that the monitor is always initialized correctly.