fix: remove failed bootstrap registrations

docs/api.md

@@ -190,12 +190,12 @@ later calls or undo changes already applied to workers.
 
 Workers contacted by a change must respond or exit before the call settles,
 including when a later send fails. Send failures preserve the original error;
-otherwise, at least one successful response is required and any failed response
-rejects the change. Without a send failure, an unanswered target's exit does not
-reject a change with a successful peer, including synchronous exits from
-protected dispatch hooks. All targets exiting unanswered rejects the change.
-Deno and Bun preserve buffered operation results before an observed unexpected
-exit; browsers preserve only already-delivered results.
+otherwise, at least one accepted response is required and any other failed
+response rejects the change. Without a send failure, an unanswered target's exit
+does not reject a change with a successful peer, including synchronous exits
+from protected dispatch hooks. All targets exiting unanswered rejects the
+change. Deno and Bun preserve buffered operation results before an observed
+unexpected exit; browsers preserve only already-delivered results.
 
 New and replacement workers wait for ongoing task function changes. They accept
 tasks only after restoring successfully registered task functions, the selected
@@ -210,12 +210,13 @@ are enabled.
 
 Custom worker subclasses that defer task function operations must echo the
 request's `taskFunctionOperationId` in their acknowledgement, or retain the
-original `taskFunctionProperties` object when using the standard transport. An
-acknowledgement without a recoverable UUID rejects the operation. Pool-wide
-changes still wait for all contacted workers to respond or exit. Status-only
-overrides that discard this correlation must be updated. Deno and Bun preserve
-incoming asynchronous context; browsers preserve only synchronous context.
-Deferred browser handlers must retain the UUID or original properties object.
+original `taskFunctionProperties` object when using the standard transport.
+Preserve result metadata when forwarding acknowledgements. An acknowledgement
+without a recoverable UUID rejects the operation. Pool-wide changes still wait
+for all contacted workers to respond or exit. Status-only overrides that discard
+this correlation must be updated. Deno and Bun preserve incoming asynchronous
+context; browsers preserve only synchronous context. Deferred browser handlers
+must retain the UUID or original properties object.
 
 ### `pool.removeTaskFunction(name)`
 
@@ -224,6 +225,10 @@ Deferred browser handlers must retain the UUID or original properties object.
 This method is available on both pool implementations and returns a boolean
 promise.
 
+For workers whose initialization failed, confirmed absence of the requested
+function also counts as successful removal. Other removal errors still reject
+the call.
+
 ### `pool.listTaskFunctionsProperties()`
 
 This method is available on both pool implementations and returns an array of

src/pools/abstract-pool.ts

@@ -947,6 +947,7 @@ export abstract class AbstractPool<
     if (this.workerNodes.length === 0) {
       return true
     }
+    const { taskFunctionOperation } = message
     const taskFunctionOperationId = crypto.randomUUID()
     const responsesReceived = new Map<
       WorkerInfo['id'] | undefined,
@@ -1011,7 +1012,19 @@ export abstract class AbstractPool<
           protocolError ??= this.getTaskFunctionOperationAcknowledgementError(
             message.workerId,
           )
-        } else if (!message.taskFunctionOperationStatus) {
+        } else if (
+          !message.taskFunctionOperationStatus &&
+          !(
+            taskFunctionOperation === 'remove' &&
+            message.taskFunctionOperationNotFound === true &&
+            message.workerError == null &&
+            this.failedWorkerTaskFunctionBootstraps.has(
+              this.workerNodes[
+                this.getWorkerNodeKeyByWorkerId(message.workerId)
+              ],
+            )
+          )
+        ) {
           errorResponse ??= message
         }
         complete()

src/utility-types.ts

@@ -188,6 +188,10 @@ export interface MessageValue<Data = unknown, ErrorData = unknown>
    * Task function operation request UUID.
    */
   readonly taskFunctionOperationId?: UUID
+  /**
+   * Whether removal confirmed that the requested task function was absent.
+   */
+  readonly taskFunctionOperationNotFound?: boolean
   /**
    * Whether the task function operation is successful or not.
    */

src/worker/abstract-worker.ts

@@ -131,6 +131,12 @@ export abstract class AbstractWorker<
    */
   protected activeInterval?: ReturnType<typeof setInterval>
 
+  /**
+   * The base removal result and name that confirm absence for the current operation.
+   */
+  private missingTaskFunctionRemoval?: TaskFunctionOperationResult
+  private missingTaskFunctionRemovalName?: string
+
   /**
    * Correlation of task function operations across protected handler overrides.
    */
@@ -308,7 +314,12 @@ export abstract class AbstractWorker<
       }
       const deleteStatus = this.taskFunctions.delete(name)
       this.sendTaskFunctionsPropertiesToMainWorker()
-      return { status: deleteStatus }
+      const response = { status: deleteStatus }
+      if (!deleteStatus) {
+        this.missingTaskFunctionRemoval = response
+        this.missingTaskFunctionRemovalName = name
+      }
+      return response
     } catch (error) {
       return { status: false, error: error as Error }
     }
@@ -466,6 +477,7 @@ export abstract class AbstractWorker<
         'Cannot handle task function operation message without task function properties',
       )
     }
+    let taskFunctionOperationNotFound = false
     let response: TaskFunctionOperationResult
     switch (taskFunctionOperation) {
       case 'add':
@@ -493,7 +505,19 @@ export abstract class AbstractWorker<
         response = this.setDefaultTaskFunction(taskFunctionProperties.name)
         break
       case 'remove':
-        response = this.removeTaskFunction(taskFunctionProperties.name)
+        this.missingTaskFunctionRemoval = undefined
+        this.missingTaskFunctionRemovalName = undefined
+        try {
+          const name = taskFunctionProperties.name
+          response = this.removeTaskFunction(name)
+          taskFunctionOperationNotFound = !response.status &&
+            response.error == null &&
+            Object.is(response, this.missingTaskFunctionRemoval) &&
+            Object.is(name, this.missingTaskFunctionRemovalName)
+        } finally {
+          this.missingTaskFunctionRemoval = undefined
+          this.missingTaskFunctionRemovalName = undefined
+        }
         break
       default:
         response = {
@@ -510,6 +534,7 @@ export abstract class AbstractWorker<
       taskFunctionOperationId: this.getTaskFunctionOperationId(message),
       taskFunctionOperationStatus: status,
       taskFunctionProperties,
+      ...(taskFunctionOperationNotFound && { taskFunctionOperationNotFound }),
       ...(!status &&
         error != null && {
         workerError: {