From ca748344cd6af59522b303f48e7e6c37f54b042d Mon Sep 17 00:00:00 2001
From: Michal Piechowiak <misiek.piechowiak@gmail.com>
Date: Tue, 29 Jun 2021 12:22:20 +0200
Subject: [PATCH] address Vlad's comment

---
 .../gatsby-worker/src/__tests__/task-queue.ts | 37 +++++++++++++++++++
 packages/gatsby-worker/src/task-queue.ts      |  3 ++
 2 files changed, 40 insertions(+)

diff --git a/packages/gatsby-worker/src/__tests__/task-queue.ts b/packages/gatsby-worker/src/__tests__/task-queue.ts
index 66caa5048b1cd..fd8dc3d7e2d8d 100644
--- a/packages/gatsby-worker/src/__tests__/task-queue.ts
+++ b/packages/gatsby-worker/src/__tests__/task-queue.ts
@@ -198,4 +198,41 @@ describe(`Task Queue`, () => {
       ]
     `)
   })
+
+  describe(`Removed node is not referenced in .next or .prev`, () => {
+    let taskQueue: TaskQueue<number>
+    beforeEach(() => {
+      taskQueue = new TaskQueue<number>()
+
+      taskQueue.enqueue(1)
+      taskQueue.enqueue(2)
+      taskQueue.enqueue(3)
+    })
+
+    it.each([
+      [`removed from head`, 1],
+      [`removed from middle`, 2],
+      [`removed from tail`, 3],
+    ])(`%s`, (_label, itemToRemove) => {
+      for (const item of taskQueue) {
+        if (item.value === itemToRemove) {
+          taskQueue.remove(item)
+        }
+      }
+
+      for (const item of taskQueue) {
+        if (item.value === itemToRemove) {
+          fail(`"${itemToRemove}" found as value`)
+        }
+
+        if (item?.prev?.value === itemToRemove) {
+          fail(`"${itemToRemove}" found as value of previous node`)
+        }
+
+        if (item?.next?.value === itemToRemove) {
+          fail(`"${itemToRemove}" found as value of next node`)
+        }
+      }
+    })
+  })
 })
diff --git a/packages/gatsby-worker/src/task-queue.ts b/packages/gatsby-worker/src/task-queue.ts
index ee390148484c8..42945763e3952 100644
--- a/packages/gatsby-worker/src/task-queue.ts
+++ b/packages/gatsby-worker/src/task-queue.ts
@@ -41,6 +41,9 @@ export class TaskQueue<ValueType> {
     } else {
       if (taskNode === this.tail) {
         this.tail = taskNode.prev
+      } else {
+        // if node is not the tail then it will have .next
+        taskNode.next!.prev = taskNode.prev
       }
       // if node is not the head then it will have .prev
       taskNode.prev!.next = taskNode.next