Just an Azure DevOps meme...

meme.ts

class Project {
  private _workItems: WorkItem[] = [];

  public get workItems(): WorkItem[] {
    return this._workItems;
  }

  public addWorkItem(item: WorkItem): number {
    const id = this._workItems.push(item);
    item.id = id;

    return id;
  }
}

type State = 'New' | 'Active' | 'Resolved' | 'QA' | 'Closed';
type BugRootCause = 'Unknown' | 'Coding Error' | 'Communication Error'
  | 'Design Error' | 'Specification Error';

interface User {
  name: string;
}
interface Comment {
  content: string;
  author: User;
  timestamp: string;
}

abstract class WorkItem {
  public id: number;
  public state: State = 'New';
  private _children: number[] = [];
  private _comments: Comment[] = [];
  public readonly createdAt: string = Date.now().toString();

  public get children() {
    return this._children;
  }
  public get comments() {
    return this._comments;
  }

  constructor (
    public assignedTo?: User,
    public priority?: 1 | 2 | 3 | 4,
  ) {}

  public get isItDone(): boolean {
    return ['Resolved', 'QA', 'Closed'].includes(this.state);
  }

  public get isItDoneDone(): boolean {
    return this.state === 'Closed';
  }

  public addChild(id: number): number {
    return this._children.push(id);
  }

  public addComment(comment: Comment) {
    this._comments.push(comment);
  }
}

class UserStory extends WorkItem {
  constructor (
    public assignedTo?: User,
    public priority?: 1 | 2 | 3 | 4,
    public points?: 1 | 3 | 5,
    public acceptanceCriteria?: string,
  ) { super(assignedTo, priority); }
}

class Bug extends WorkItem {
  public rootCause: BugRootCause;
  public type: string;

  constructor (
    public assignedTo?: User,
    public priority?: 1 | 2 | 3 | 4,
    public severity?: 1 | 2 | 3 | 4,
    public reproSteps?: string,
  ) { super(assignedTo, priority); }
}

class Task extends WorkItem {}

const project = new Project();
const story = new UserStory(
  { name: 'Alex Garcia' },
  1,
  5,
  'Given Alex Garcia has this ticket\nWhen he completes it\nThen it will be "Done Done"',
);

project.addWorkItem(story);
console.log('is it done?', story.isItDone);
console.log('is it "Done Done"?', story.isItDoneDone);

console.log('Opening PR...');
story.state = 'Resolved';
console.log('is it done?', story.isItDone);
console.log('is it "Done Done"?', story.isItDoneDone);

console.log('Merging Dev to UAT...');
story.state = 'QA';
console.log('is it done?', story.isItDone);
console.log('is it "Done Done"?', story.isItDoneDone);

console.log('QA Verified!');
story.state = 'Closed';
console.log('is it done?', story.isItDone);
console.log('is it "Done Done"?', story.isItDoneDone);