From a81e8c1ea080984ddd6d5e58c154b866ee44c14c Mon Sep 17 00:00:00 2001
From: enisdenjo <badurinadenis@gmail.com>
Date: Sun, 1 Nov 2020 00:32:28 +0100
Subject: [PATCH] fix: Drop TypeScript DOM lib dependency

---
 src/client.ts | 22 +++++++++++++++++++---
 src/types.ts  |  9 +++++++--
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/src/client.ts b/src/client.ts
index 902125c3..1be4495d 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -20,12 +20,28 @@ export type EventConnected = 'connected'; // connected = socket opened + acknowl
 export type EventClosed = 'closed';
 export type Event = EventConnecting | EventConnected | EventClosed;
 
+/**
+ * The argument is actually the `WebSocket`, but to avoid bundling DOM typings
+ * because the client can run in Node env too, you should assert
+ * the websocket type during implementation.
+ */
+export type EventConnectedHandler = (socket: unknown) => void;
+
+export type EventConnectingHandler = () => void;
+
+/**
+ * The argument is actually the websocket `CloseEvent`, but to avoid
+ * bundling DOM typings because the client can run in Node env too,
+ * you should assert the websocket type during implementation.
+ */
+export type EventClosedHandler = (event: unknown) => void;
+
 export type EventListener<E extends Event> = E extends EventConnecting
-  ? () => void
+  ? EventConnectingHandler
   : E extends EventConnected
-  ? (socket: WebSocket) => void
+  ? EventConnectedHandler
   : E extends EventClosed
-  ? (event: CloseEvent) => void
+  ? EventClosedHandler
   : never;
 
 type CancellerRef = { current: (() => void) | null };
diff --git a/src/types.ts b/src/types.ts
index 43fbc351..2777fcd9 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -24,8 +24,13 @@ export interface Disposable {
 export interface Sink<T = unknown> {
   /** Next value arriving. */
   next(value: T): void;
-  /** An error that has occured. Calling this function "closes" the sink. */
-  error(error: Error | CloseEvent | readonly GraphQLError[]): void;
+  /**
+   * An error that has occured. Calling this function "closes" the sink.
+   * The error can be also `CloseEvent`, but to avoid bundling DOM typings
+   * because the client can run in Node env too, you should assert
+   * the close event type during implementation.
+   */
+  error(error: Error | readonly GraphQLError[] | unknown): void;
   /** The sink has completed. This function "closes" the sink. */
   complete(): void;
 }