Is msgpackr deterministic?

[Llorx]

I've found that V8.serialize() is not deterministic. You can serialize the same object, but created at different times, and you can receive different outputs because of how V8 internals work: nodejs/help#2448

I'm thinking a way to serialize an object and receive the same output, no matter if I pushed/spliced/whatever the arrays, Maps and Sets. Is this msgpackr case?

Thank you.

[kriszyp]

Yes, msgpackr is deterministic: ordering of serialization follows the natural iterative order of objects, maps, and sets (order of insertion).

[Llorx]

To be clear, I don't mean ordering of serialization, but internal object representation. In V8, two very same exact arrays could lead to different representation because one was just created and the other had a push and a pop. I see that msgpackr has native addons so I don't know how it works with memory.

[kriszyp]

Yes, all msgpackr serialization should be deterministic, including arrays (exactly identical arrays should serialize to identical binary output). The native addon is only used for decoding/deserialization.