clear timeout on rejected command (#36)

Author: fatal10110

lib/Command.ts

@@ -339,6 +339,12 @@ export default class Command implements Respondable {
       } else {
         this.reject = reject;
       }
+    }).finally(() => {
+      const existingTimer = this._commandTimeoutTimer;
+      if (existingTimer) {
+        clearTimeout(existingTimer);
+        delete this._commandTimeoutTimer;
+      }
     });
 
     this.promise = asCallback(promise, this.callback);
@@ -370,12 +376,6 @@ export default class Command implements Respondable {
   private _convertValue(resolve: Function): (result: any) => void {
     return (value) => {
       try {
-        const existingTimer = this._commandTimeoutTimer;
-        if (existingTimer) {
-          clearTimeout(existingTimer);
-          delete this._commandTimeoutTimer;
-        }
-
         resolve(this.transformReply(value));
         this.isResolved = true;
       } catch (err) {

package-lock.json

@@ -34,4 +34,27 @@ describe("commandTimeout", () => {
     redis.disconnect();
     await server.disconnectPromise();
   });
+
+  it("does not leak timers on rejected commands", async () => {
+    const server = new MockServer(30001, (argv, socket, flags) => {
+      if (argv[0] === "evalsha") {
+        return new Error("test error");
+      }
+    });
+
+    const redis = new Redis({ port: 30001, commandTimeout: 1000000000 });
+    const clock = sinon.useFakeTimers();
+    let error: any;
+    try {
+      await redis.evalsha("asd", 0);
+    } catch (err) {
+      error = err;
+    }
+
+    expect(error.message).to.eql("test error");
+    expect(clock.countTimers()).to.eql(0);
+    clock.restore();
+    redis.disconnect();
+    server.disconnect();
+  });
 });