Switch Jint support to use version 3 previews

[lahma]

Could you consider a PR which would change the used Jint version to 3 preview build? Version 3 has:

• new ES6 features
• performance improvements
• same set of tests as 2.x and on top of that all the new relevant ES6 tests, thousands of test cases in total
• the preview label only to allow moving the cheese if needed

There would be one obvious breaking change though. The oldest supported .NET full framework version is 4.5, and might even change to something like 4.6.1 later on. But the general guidance seems to be to support .NET 4.6.1 and .NET Standard 2.0, older versions are at the end of the road.

[Taritsyn]

Hello, Marko!

I added support of the Jint version 3.0.0 Beta 1598 in the JavaScriptEngineSwitcher.Jint module (9c144b2).

At the moment, unit tests defined in the PrecompilationTestsBase class are failing (error is unstable and is associated with multithreading). I may have to store the instance of the Esprima.Ast.Program class in serialized form.

[lahma]

Great news, thank you for following up so quickly! Engine indeed is not thread-safe and should not be shared between threads. If you have time at some point to run benchmarks, I'd love to hear about possible performance improvements 🙂

[Taritsyn]

Hello, Marko!

To make release and real benchmarks I need a new version of the Jint package that will include fixes for error #667.

[lahma]

Thanks, pinging @sebastienros for a new release

[sebastienros]

https://www.nuget.org/packages/Jint/3.0.0-beta-1612

[Taritsyn]

Thanks! Tomorrow I will make release.

In the meantime, here are the results of the JsExecutionBenchmark benchmark:

.NET Framework 4.6.1

Jint v2.11.58

| Method | withPrecompilation |     Mean |     Error |    StdDev |     Gen 0 |     Gen 1 |   Gen 2 | Allocated |
|------- |------------------- |---------:|----------:|----------:|----------:|----------:|--------:|----------:|
|   Jint |              False | 24.12 ms | 0.1001 ms | 0.0836 ms | 2781.2500 | 1375.0000 |       - |  16.04 MB |
|   Jint |               True | 14.98 ms | 0.2813 ms | 0.3557 ms | 1281.2500 |  609.3750 | 93.7500 |   7.37 MB |

Jint v3.0.0 Beta 1612

| Method | withPrecompilation |      Mean |     Error |    StdDev |     Gen 0 | Gen 1 | Gen 2 | Allocated |
|------- |------------------- |----------:|----------:|----------:|----------:|------:|------:|----------:|
|   Jint |              False | 12.698 ms | 0.1049 ms | 0.0930 ms | 1000.0000 |     - |     - |   7.31 MB |
|   Jint |               True |  4.917 ms | 0.0915 ms | 0.0940 ms |         - |     - |     - |   2.63 MB |

.NET Core App 2.0

Jint v2.11.58

| Method | withPrecompilation |     Mean |     Error |    StdDev |     Gen 0 |     Gen 1 |   Gen 2 | Allocated |
|------- |------------------- |---------:|----------:|----------:|----------:|----------:|--------:|----------:|
|   Jint |              False | 24.01 ms | 0.3713 ms | 0.3291 ms | 2750.0000 | 1375.0000 |       - |  15.92 MB |
|   Jint |               True | 14.53 ms | 0.2710 ms | 0.2661 ms | 1265.6250 |  593.7500 | 62.5000 |   7.27 MB |

Jint v3.0.0 Beta 1612

| Method | withPrecompilation |      Mean |     Error |    StdDev |     Gen 0 | Gen 1 | Gen 2 | Allocated |
|------- |------------------- |----------:|----------:|----------:|----------:|------:|------:|----------:|
|   Jint |              False | 12.842 ms | 0.1123 ms | 0.0995 ms | 1000.0000 |     - |     - |   7.27 MB |
|   Jint |               True |  5.062 ms | 0.1173 ms | 0.1441 ms |         - |     - |     - |   2.61 MB |

[lahma]

I like these numbers 🥳

[sebastienros]

Good job Marko, and thanks Andrey.

[lahma]

Thank you @Taritsyn for upgrading, I hope the new version is a worthwhile upgrade.