Refactor evaluations (#285)

* Replace evaluations with proxies and messages

* Return proxies synchronously

Otherwise events can be lost.

* Ensure events cannot be missed

* Refactor remaining fills

* Use more up-to-date version of util

For callbackify.

* Wait for dispose to come back before removing

This prevents issues with the "done" event not always being the last
event fired. For example a socket might close and then end, but only
if the caller called end.

* Remove old node-pty tests

* Fix emitting events twice on duplex streams

* Preserve environment when spawning processes

* Throw a better error if the proxy doesn't exist

* Remove rimraf dependency from ide

* Update net.Server.listening

* Use exit event instead of killed

Doesn't look like killed is even a thing.

* Add response timeout to server

* Fix trash

* Require node-pty & spdlog after they get unpackaged

This fixes an error when running in the binary.

* Fix errors in down emitter preventing reconnecting

* Fix disposing proxies when nothing listens to "error" event

* Refactor event tests to use jest.fn()

* Reject proxy call when disconnected

Otherwise it'll wait for the timeout which is a waste of time since we
already know the connection is dead.

* Use nbin for binary packaging

* Remove additional module requires

* Attempt to remove require for local bootstrap-fork

* Externalize fsevents

packages/protocol/src/common/proxy.ts

@@ -0,0 +1,83 @@
+import { EventEmitter } from "events";
+import { isPromise } from "./util";
+
+// tslint:disable no-any
+
+/**
+ * Allow using a proxy like it's returned synchronously. This only works because
+ * all proxy methods return promises.
+ */
+const unpromisify = <T extends ServerProxy>(proxyPromise: Promise<T>): T => {
+	return new Proxy({}, {
+		get: (target: any, name: string): any => {
+			if (typeof target[name] === "undefined") {
+				target[name] = async (...args: any[]): Promise<any> => {
+					const proxy = await proxyPromise;
+
+					return proxy ? (proxy as any)[name](...args) : undefined;
+				};
+			}
+
+			return target[name];
+		},
+	});
+};
+
+/**
+ * Client-side emitter that just forwards proxy events to its own emitter.
+ * It also turns a promisified proxy into a non-promisified proxy so we don't
+ * need a bunch of `then` calls everywhere.
+ */
+export abstract class ClientProxy<T extends ServerProxy> extends EventEmitter {
+	protected readonly proxy: T;
+
+	/**
+	 * You can specify not to bind events in order to avoid emitting twice for
+	 * duplex streams.
+	 */
+	public constructor(proxyPromise: Promise<T> | T, bindEvents: boolean = true) {
+		super();
+		this.proxy = isPromise(proxyPromise) ? unpromisify(proxyPromise) : proxyPromise;
+		if (bindEvents) {
+			this.proxy.onEvent((event, ...args): void => {
+				this.emit(event, ...args);
+			});
+		}
+	}
+}
+
+/**
+ * Proxy to the actual instance on the server. Every method must only accept
+ * serializable arguments and must return promises with serializable values. If
+ * a proxy itself has proxies on creation (like how ChildProcess has stdin),
+ * then it should return all of those at once, otherwise you will miss events
+ * from those child proxies and fail to dispose them properly.
+ */
+export interface ServerProxy {
+	dispose(): Promise<void>;
+
+	/**
+	 * This is used instead of an event to force it to be implemented since there
+	 * would be no guarantee the implementation would remember to emit the event.
+	 */
+	onDone(cb: () => void): Promise<void>;
+
+	/**
+	 * Listen to all possible events. On the client, this is to reduce boilerplate
+	 * that would just be a bunch of error-prone forwarding of each individual
+	 * event from the proxy to its own emitter. It also fixes a timing issue
+	 * because we just always send all events from the server, so we never miss
+	 * any due to listening too late.
+	 */
+	// tslint:disable-next-line no-any
+	onEvent(cb: (event: string, ...args: any[]) => void): Promise<void>;
+}
+
+export enum Module {
+	Fs = "fs",
+	ChildProcess = "child_process",
+	Net = "net",
+	Spdlog = "spdlog",
+	NodePty = "node-pty",
+	Trash = "trash",
+}