Events queue in emitter can grow without bound, leading to "out of memory" in runtime

[vjorlikowski]

While generating large YAML documents in one of our projects, we encountered an issue where we could easily run out of memory in the emitter.

It turned out that the reason was that the events queue was growing without bound.

We have patched this in a fork, possibly in a sub-optimal fashion; the patch can be found here:

a24d571

The "deep-copy-to-shrink" strategy may not be ideal (lots of allocs, lots of GC), but it allows our document generation to successfully complete.

[costela]

We also observe a similar phenomenon, causing multiple megabytes of memory usage when dumping a ~400kb YAML file:

(this is 2.4.0, but the code in question does not seem to have been touched in v3?)