From f2495e5ee9ecdb26492da510dc38730718cb28c5 Mon Sep 17 00:00:00 2001
From: Manuel Astudillo <manuel@optimalbits.com>
Date: Thu, 14 Nov 2024 16:14:23 +0100
Subject: [PATCH] fix(queue): fix generics to be able to properly be extended

---
 src/classes/queue.ts | 92 ++++++++++++++++++++++++++++++++++----------
 1 file changed, 72 insertions(+), 20 deletions(-)

diff --git a/src/classes/queue.ts b/src/classes/queue.ts
index 84cfbcacaf..6601784cdf 100644
--- a/src/classes/queue.ts
+++ b/src/classes/queue.ts
@@ -29,7 +29,7 @@ export interface ObliterateOpts {
   count?: number;
 }
 
-export interface QueueListener<DataType, ResultType, NameType extends string>
+export interface QueueListener<JobBase extends Job = Job>
   extends IoredisListener {
   /**
    * Listen to 'cleaned' event.
@@ -57,17 +57,14 @@ export interface QueueListener<DataType, ResultType, NameType extends string>
    *
    * This event is triggered when the job updates its progress.
    */
-  progress: (
-    job: Job<DataType, ResultType, NameType>,
-    progress: number | object,
-  ) => void;
+  progress: (job: JobBase, progress: number | object) => void;
 
   /**
    * Listen to 'removed' event.
    *
    * This event is triggered when a job is removed.
    */
-  removed: (job: Job<DataType, ResultType, NameType>) => void;
+  removed: (job: JobBase) => void;
 
   /**
    * Listen to 'resumed' event.
@@ -81,21 +78,74 @@ export interface QueueListener<DataType, ResultType, NameType extends string>
    *
    * This event is triggered when the queue creates a new job.
    */
-  waiting: (job: Job<DataType, ResultType, NameType>) => void;
+  waiting: (job: JobBase) => void;
 }
 
+// Helper for JobBase type
+type JobBase<T, ResultType, NameType extends string> = T extends Job<
+  any,
+  any,
+  any
+>
+  ? T
+  : Job<T, ResultType, NameType>;
+
+// Helper types to extract DataType, ResultType, and NameType
+type ExtractDataType<DataTypeOrJob, Default> = DataTypeOrJob extends Job<
+  infer D,
+  any,
+  any
+>
+  ? D
+  : Default;
+
+type ExtractResultType<DataTypeOrJob, Default> = DataTypeOrJob extends Job<
+  any,
+  infer R,
+  any
+>
+  ? R
+  : Default;
+
+type ExtractNameType<
+  DataTypeOrJob,
+  Default extends string,
+> = DataTypeOrJob extends Job<any, any, infer N> ? N : Default;
+
 /**
  * Queue
  *
  * This class provides methods to add jobs to a queue and some other high-level
  * administration such as pausing or deleting queues.
  *
+ * @template DataType - The type of the data that the job will process.
+ * @template ResultType - The type of the result of the job.
+ * @template NameType - The type of the name of the job.
+ *
+ * @example
+ *
+ * ```typescript
+ * import { Queue } from 'bullmq';
+ *
+ * interface MyDataType {
+ *  foo: string;
+ * }
+ *
+ * interface MyResultType {
+ *   bar: string;
+ * }
+ *
+ * const queue = new Queue<MyDataType, MyResultType, "blue" | "brown">('myQueue');
+ * ```
  */
 export class Queue<
-  DataType = any,
-  ResultType = any,
-  NameType extends string = string,
-> extends QueueGetters<Job<DataType, ResultType, NameType>> {
+  DataTypeOrJob = any,
+  DefaultResultType = any,
+  DefaultNameType extends string = string,
+  DataType = ExtractDataType<DataTypeOrJob, DataTypeOrJob>,
+  ResultType = ExtractResultType<DataTypeOrJob, DefaultResultType>,
+  NameType extends string = ExtractNameType<DataTypeOrJob, DefaultNameType>,
+> extends QueueGetters<JobBase<DataTypeOrJob, ResultType, NameType>> {
   token = v4();
   jobsOpts: BaseJobOptions;
   opts: QueueOptions;
@@ -132,32 +182,34 @@ export class Queue<
       });
   }
 
-  emit<U extends keyof QueueListener<DataType, ResultType, NameType>>(
+  emit<U extends keyof QueueListener<JobBase<DataType, ResultType, NameType>>>(
     event: U,
-    ...args: Parameters<QueueListener<DataType, ResultType, NameType>[U]>
+    ...args: Parameters<
+      QueueListener<JobBase<DataType, ResultType, NameType>>[U]
+    >
   ): boolean {
     return super.emit(event, ...args);
   }
 
-  off<U extends keyof QueueListener<DataType, ResultType, NameType>>(
+  off<U extends keyof QueueListener<JobBase<DataType, ResultType, NameType>>>(
     eventName: U,
-    listener: QueueListener<DataType, ResultType, NameType>[U],
+    listener: QueueListener<JobBase<DataType, ResultType, NameType>>[U],
   ): this {
     super.off(eventName, listener);
     return this;
   }
 
-  on<U extends keyof QueueListener<DataType, ResultType, NameType>>(
+  on<U extends keyof QueueListener<JobBase<DataType, ResultType, NameType>>>(
     event: U,
-    listener: QueueListener<DataType, ResultType, NameType>[U],
+    listener: QueueListener<JobBase<DataType, ResultType, NameType>>[U],
   ): this {
     super.on(event, listener);
     return this;
   }
 
-  once<U extends keyof QueueListener<DataType, ResultType, NameType>>(
+  once<U extends keyof QueueListener<JobBase<DataType, ResultType, NameType>>>(
     event: U,
-    listener: QueueListener<DataType, ResultType, NameType>[U],
+    listener: QueueListener<JobBase<DataType, ResultType, NameType>>[U],
   ): this {
     super.once(event, listener);
     return this;
@@ -290,7 +342,7 @@ export class Queue<
               jobId,
             },
           );
-          this.emit('waiting', job);
+          this.emit('waiting', job as JobBase<DataType, ResultType, NameType>);
 
           span?.setAttributes({
             [TelemetryAttributes.JobId]: job.id,