2020-02-11, Version 12.16.0 'Erbium' (LTS)

Notable changes:

New assert APIs

The `assert` module now provides experimental `assert.match()` and
`assert.doesNotMatch()` methods. They will validate that the first argument is a
string and matches (or does not match) the provided regular expression

This is an experimental feature.

Ruben Bridgewater [#30929](https://github.com/nodejs/node/pull/30929).

Advanced serialization for IPC

The `child_process` and `cluster` modules now support a `serialization` option
to change the serialization mechanism used for IPC. The option can have one of
two values:

* `'json'` (default): `JSON.stringify()` and `JSON.parse()` are used. This is
  how message serialization was done before.
* `'advanced'`: The serialization API of the `v8` module is used. It is based on
  the HTML structured clone algorithm.
  and is able to serialize more built-in JavaScript object types, such as
  `BigInt`, `Map`, `Set` etc. as well as circular data structures.

Anna Henningsen [#30162](https://github.com/nodejs/node/pull/30162).

CLI flags

The new `--trace-exit` CLI flag makes Node.js print a stack trace whenever the
Node.js environment is exited proactively (i.e. by invoking the `process.exit()`
function or pressing Ctrl+C).

legendecas [#30516](https://github.com/nodejs/node/pull/30516).

___

The new `--trace-uncaught` CLI flag makes Node.js print a stack trace at the
time of throwing uncaught exceptions, rather than at the creation of the `Error`
object, if there is any.
This option is not enabled by default because it may affect garbage collection
behavior negatively.

Anna Henningsen [#30025](https://github.com/nodejs/node/pull/30025).

___

The `--disallow-code-generation-from-strings` V8 CLI flag is now whitelisted in
the `NODE_OPTIONS` environment variable.

Shelley Vohr [#30094](https://github.com/nodejs/node/pull/30094).

New crypto APIs

For DSA and ECDSA, a new signature encoding is now supported in addition to the
existing one (DER). The `verify` and `sign` methods accept a `dsaEncoding`
option, which can have one of two values:

* `'der'` (default): DER-encoded ASN.1 signature structure encoding `(r, s)`.
* `'ieee-p1363'`: Signature format `r || s` as proposed in IEEE-P1363.

Tobias Nießen [#29292](https://github.com/nodejs/node/pull/29292).

___

A new method was added to `Hash`: `Hash.prototype.copy`. It makes it possible to
clone the internal state of a `Hash` object into a new `Hash` object, allowing
to compute the digest between updates.

Ben Noordhuis [#29910](https://github.com/nodejs/node/pull/29910).

Dependency updates

libuv was updated to 1.34.0. This includes fixes to `uv_fs_copyfile()` and
`uv_interface_addresses()` and adds two new functions: `uv_sleep()` and
`uv_fs_mkstemp()`.

Colin Ihrig [#30783](https://github.com/nodejs/node/pull/30783).

___

V8 was updated to 7.8.279.23. This includes performance improvements to object
destructuring, RegExp match failures and WebAssembly startup time.
The official release notes are available at https://v8.dev/blog/v8-release-78.

Michaël Zasso [#30109](https://github.com/nodejs/node/pull/30109).

New EventEmitter APIs

The new `EventEmitter.on` static method allows to async iterate over events.

Matteo Collina [#27994](https://github.com/nodejs/node/pull/27994).

___

It is now possible to monitor `'error'` events on an `EventEmitter` without
consuming the emitted error by installing a listener using the symbol
`EventEmitter.errorMonitor`.

Gerhard Stoebich [#30932](https://github.com/nodejs/node/pull/30932).

___

Using `async` functions with event handlers is problematic, because it
can lead to an unhandled rejection in case of a thrown exception.

The experimental `captureRejections` option in the `EventEmitter` constructor or
the global setting change this behavior, installing a
`.then(undefined, handler)` handler on the `Promise`. This handler routes the
exception asynchronously to the `Symbol.for('nodejs.rejection')` method if there
is one, or to the `'error'` event handler if there is none.

Setting `EventEmitter.captureRejections = true` will change the default for all
new instances of `EventEmitter`.

This is an experimental feature.

Matteo Collina [#27867](https://github.com/nodejs/node/pull/27867).

Performance Hooks are no longer experimental

The `perf_hooks` module is now considered a stable API.

legendecas [#31101](https://github.com/nodejs/node/pull/31101).

Introduction of experimental WebAssembly System Interface (WASI) support

A new core module, `wasi`, is introduced to provide an implementation of the
[WebAssembly System Interface](https://wasi.dev/) specification.
WASI gives sandboxed WebAssembly applications access to the
underlying operating system via a collection of POSIX-like functions.

This is an experimental feature.

Colin Ihrig [#30258](https://github.com/nodejs/node/pull/30258).

PR-URL: https://github.com/nodejs/node/pull/31691