More perf issues with closure classes

Looks like V8 really hates those closure classes. Its taking 36s to generate 100 samples, with most of the time spent in the generate method of:

  noBias(): Arbitrary<T> {
    const arb = this;
    return new class extends Arbitrary<T> {
      generate(mrng: Random): Shrinkable<T> {
        return arb.generate(mrng);
      }
    }();
  }

Should I try to do a PR that removes them all?

[dubzzz]

I just replayed the tests on my computer by modifying package.json file between each performance test:

  "dependencies": {
    "fast-check": "1.5.0",
    "pure-rand": "1.1.1"
  }

Resulted in:

yarn run v1.10.1
$ tsc && node src/index
perf: 147862.483ms
Asertion count: 20000
Done in 149.53s.

While:

  "dependencies": {
    "fast-check": "1.7.1",
    "pure-rand": "1.5.0"
  }

Resulted in:

yarn run v1.10.1
$ tsc && node src/index
perf: 73844.808ms
Asertion count: 20000
Done in 75.49s.

[dubzzz]

@spion Next version of fast-check will feature a way to change the random generator by setting the randomType attribute - see #200 - switching to congruential32 might reduce the time taken to generate values.

Meanwhile I am looking for ways to accelerate the generation of values by reducing gc, recompile…