From 5562b190d63901984f50deb85cbb56f0b9a1b914 Mon Sep 17 00:00:00 2001
From: Luca Casonato <lucacasonato@yahoo.com>
Date: Fri, 2 Apr 2021 00:55:22 +0200
Subject: [PATCH] fix(websocket): ignore resource close error (#9755)

It is possible that the WebSocket is already closed when we try to
close it with `WebSocket#close` or in the `error` or `close` events.
Currently this leads to an uncatchable promise rejection. This changes
this so that closing an already closed WebSocket is a noop.
---
 op_crates/websocket/01_websocket.js | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/op_crates/websocket/01_websocket.js b/op_crates/websocket/01_websocket.js
index 4a303679b5..67fc0e4812 100644
--- a/op_crates/websocket/01_websocket.js
+++ b/op_crates/websocket/01_websocket.js
@@ -25,6 +25,19 @@
     }
   }
 
+  /**
+   * Tries to close the resource (and ignores BadResource errors).
+   * @param {number} rid
+   */
+  function tryClose(rid) {
+    try {
+      core.close(rid);
+    } catch (err) {
+      // Ignore error if the socket has already been closed.
+      if (!(err instanceof Deno.errors.BadResource)) throw err;
+    }
+  }
+
   const handlerSymbol = Symbol("eventHandlers");
   function makeWrappedHandler(handler) {
     function wrappedHandler(...args) {
@@ -125,7 +138,7 @@
               const event = new CloseEvent("close");
               event.target = this;
               this.dispatchEvent(event);
-              core.close(this.#rid);
+              tryClose(this.#rid);
             });
           } else {
             this.#readyState = OPEN;
@@ -289,7 +302,7 @@
           });
           event.target = this;
           this.dispatchEvent(event);
-          core.close(this.#rid);
+          tryClose(this.#rid);
         });
       }
     }
@@ -350,7 +363,7 @@
             });
             event.target = this;
             this.dispatchEvent(event);
-            core.close(this.#rid);
+            tryClose(this.#rid);
 
             break;
           }
@@ -365,7 +378,7 @@
             const closeEv = new CloseEvent("close");
             closeEv.target = this;
             this.dispatchEvent(closeEv);
-            core.close(this.#rid);
+            tryClose(this.#rid);
 
             break;
           }