The using((arena) => ...) function provided by jni is great for ensuring that all references are disposed at the end of the code block.

There are many instances where the arena is not used to dispose the reference.
When using:

• booleanValue(releaseOriginal: true)
• intValue(releaseOriginal: true)
• toDartString(releaseOriginal: true)
• etc.

It is quite easy to mistakenly use a releaseBy(...) in conjunction with one of these functions and get yourself a DoubleReleaseError.

However using provides no helpful information about where this 2nd release is registered.

Possible Solutions

Don't throw on double release

My personal favorite

import 'dart:ffi';

import 'package:ffi/ffi.dart';
/// Runs [computation] with a new [Arena], and releases all allocations at the
/// end.
///
/// If the return value of [computation] is a [Future], all allocations are
/// released when the future completes.
///
/// If the isolate is shut down, through `Isolate.kill()`, resources are _not_
/// cleaned up.
/// 
/// Does not throw DoubleReleaseError.
R myUsing<R>(
  R Function(Arena) computation, [
  Allocator wrappedAllocator = calloc,
]) {
  final arena = Arena(wrappedAllocator);
  var isAsync = false;
  try {
    final result = computation(arena);
    if (result is Future) {
      isAsync = true;
      return result.whenComplete(() {
            try {
              arena.releaseAll();
            } on DoubleReleaseError {
              // ignore
            }
          })
          as R;
    }
    return result;
  } finally {
    if (!isAsync) {
      try {
        arena.releaseAll();
      } on DoubleReleaseError {
        // ignore
      }
    }
  }
}

Throw on release

Add/replace an option called booleanValue(releaseWith: arena) to each built-in converter:

using((arena ){
  return JString().toDartString(releaseWith:arena);
})

The arena should store references as a set of references (Set<JReference>) or Map of references to release Callbacks (Map<JReference,Function>), adding duplicate references will throw an upon registration.
Stack traces would then contain useful information.

This is similar to the syntax that the ffi uses anyway:

final pTitle = 'Window title'.toNativeUtf16(allocator: arena);