Generate adapter code for arrays and typed arrays

[vmoroz]

Authored by jasongin on Feb 9, 2023, merged on Feb 10, 2023
Imported from jasongin/napi-dotnet repo

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• Generate adapter code for arrays: C# T[] <-> JS T[] for any T that can be converted including primitives, structs, classes, etc.
  • Unfortunately array data must be copied because it's impossible to create a C# array over external memory.
• Add JSTypedArray<T> value type.
• Generate adapter code for typed arrays: C# Memory<T> <-> JS TypedArrays, where T is one of the valid typed-array element types, for example Memory<int> <-> Int32Array.
  • Typed arrays can be passed back and forth without copying the data, with some careful marshalling and lifetime management -- see JSTypedArray.MemoryManager.
• Generate TS type definitions for arrays, typed arrays, and collections.

(Runtime adapter code is not yet generated for collections; I'm planning to work on that next. Collections should be adaptable without copying, by leveraging JS Proxy objects.)

[Hiwen]

I Test Memory<T> to TypedArray<T> on Electron 19.1.9,That Worked fine and has amazing Performance.
But when I Test on higher Electron, such as 32.1.2, it was not worked. And reported an error:

External buffers are not allowed: Error in CreateExternalArrayBuffer at D:\a\1\s\src\NodeApi\JSValue.cs:264

I did some research，the use of External buffers has actually been officially banned.
electron/electron#35801

Does anyone know how to turn on External buffers support in the new version of Electron? Like turn it on by some command parameter or something。

[jasongin]

Thanks for the comment @Hiwen, I wasn't aware of that limitation on Electron.

Let's continue discussion in #383 instead of on this old closed PR.