solution

src/App.scss

@@ -5,32 +5,3 @@ iframe {
 .App__title {
   text-align: center;
 }
-
-.PostInfo {
-  margin: 10px auto;
-  width: 90%;
-  border: 1px solid #000;
-  border-radius: 8px;
-  background-color: lightgray;
-  padding: 1em;
-
-  &__title {
-    margin: 0;
-  }
-
-  &__header {
-    margin-bottom: 1em;
-  }
-}
-
-.UserInfo {
-  font-weight: bold;
-}
-
-.CommentList {
-  display: flex;
-  flex-direction: column;
-  gap: 0.7em;
-  background-color: #eee;
-  padding: 1em;
-}

src/App.tsx

@@ -2,105 +2,44 @@ import React from 'react';
 
 import './App.scss';
 
-// import postsFromServer from './api/posts';
-// import commentsFromServer from './api/comments';
-// import usersFromServer from './api/users';
+import postsFromServer from './api/posts';
+import commentsFromServer from './api/comments';
+import usersFromServer from './api/users';
+import { User } from './types/User';
+import { Post } from './types/Post';
+import { IDGenericFunc } from './types/IDGenericFunc';
+import { PostList } from './components/PostList';
+
+function getById<T extends IDGenericFunc>(array: T[], id: number) {
+  return array.find(element => element.id === id) || null;
+}
+
+function getPostList() {
+  const posts = postsFromServer.map(post => ({
+    ...post,
+    user: getById<User>(usersFromServer, post.userId),
+    comments: [],
+  }));
+
+  commentsFromServer.forEach(comment => {
+    const post = getById<Post>(posts, comment.postId);
+    const resultComment = {
+      ...comment,
+      post,
+    };
+
+    post?.comments.push(resultComment);
+  });
+
+  return posts;
+}
+
+const postList: Post[] = getPostList();
 
 export const App: React.FC = () => (
   <section className="App">
     <h1 className="App__title">Static list of posts</h1>
 
-    <div className="PostList">
-      <div className="PostInfo">
-        <div className="PostInfo__header">
-          <h3 className="PostInfo__title">qui est esse</h3>
-
-          <p>
-            {' Posted by  '}
-
-            <a className="UserInfo" href="mailto:Sincere@april.biz">
-              Leanne Graham
-            </a>
-          </p>
-        </div>
-
-        <p className="PostInfo__body">
-          est rerum tempore vitae sequi sint nihil reprehenderit dolor beatae ea
-          dolores neque fugiat blanditiis voluptate porro vel nihil molestiae ut
-          reiciendis qui aperiam non debitis possimus qui neque nisi nulla
-        </p>
-
-        <hr />
-
-        <b data-cy="NoCommentsMessage">No comments yet</b>
-      </div>
-
-      <div className="PostInfo">
-        <div className="PostInfo__header">
-          <h3 className="PostInfo__title">doloremque illum aliquid sunt</h3>
-
-          <p>
-            {' Posted by  '}
-
-            <a className="UserInfo" href="mailto:Julianne.OConner@kory.org">
-              Patricia Lebsack
-            </a>
-          </p>
-        </div>
-
-        <p className="PostInfo__body">
-          deserunt eos nobis asperiores et hic est debitis repellat molestiae
-          optio nihil ratione ut eos beatae quibusdam distinctio maiores earum
-          voluptates et aut adipisci ea maiores voluptas maxime
-        </p>
-
-        <div className="CommentList">
-          <div className="CommentInfo">
-            <div className="CommentInfo__title">
-              <strong className="CommentInfo__name">pariatur omnis in</strong>
-
-              {' by '}
-
-              <a
-                className="CommentInfo__email"
-                href="mailto:Telly_Lynch@karl.co.uk"
-              >
-                Telly_Lynch@karl.co.uk
-              </a>
-            </div>
-
-            <div className="CommentInfo__body">
-              dolorum voluptas laboriosam quisquam ab totam beatae et aut
-              aliquid optio assumenda voluptas velit itaque quidem voluptatem
-              tempore cupiditate in itaque sit molestiae minus dolores magni
-            </div>
-          </div>
-
-          <div className="CommentInfo">
-            <div className="CommentInfo__title">
-              <strong className="CommentInfo__name">
-                odio adipisci rerum aut animi
-              </strong>
-
-              {' by '}
-
-              <a
-                className="CommentInfo__email"
-                href="mailto:Nikita@garfield.biz"
-              >
-                Nikita@garfield.biz
-              </a>
-            </div>
-
-            <div className="CommentInfo__body">
-              quia molestiae reprehenderit quasi aspernatur aut expedita
-              occaecati aliquam eveniet laudantium omnis quibusdam delectus
-              saepe quia accusamus maiores nam est cum et ducimus et vero
-              voluptates excepturi deleniti ratione
-            </div>
-          </div>
-        </div>
-      </div>
-    </div>
+    <PostList posts={postList} />
   </section>
 );

src/components/CommentInfo/CommentInfo.tsx

@@ -1,3 +1,25 @@
-import React from 'react';
+type Props = {
+  comment: {
+    name: string;
+    email: string;
+    body: string;
+  };
+};
 
-export const CommentInfo: React.FC = () => <>Put the comment here</>;
+export const CommentInfo = ({ comment: { name, email, body } }: Props) => {
+  return (
+    <div className="CommentInfo">
+      <div className="CommentInfo__title">
+        <strong className="CommentInfo__name">{name}</strong>
+
+        {' by '}
+
+        <a className="CommentInfo__email" href={`mailto:${email}`}>
+          {email}
+        </a>
+      </div>
+
+      <div className="CommentInfo__body">{body}</div>
+    </div>
+  );
+};

src/components/CommentList/CommentList.scss

@@ -1 +1,7 @@
-// add styles here
+.CommentList {
+  display: flex;
+  flex-direction: column;
+  gap: 0.7em;
+  background-color: #eee;
+  padding: 1em;
+}

src/components/CommentList/CommentList.tsx

@@ -1,3 +1,18 @@
 import React from 'react';
+import { Comment } from '../../types/Comment';
+import { CommentInfo } from '../CommentInfo';
+import './CommentList.scss';
 
-export const CommentList: React.FC = () => <>Put the list here</>;
+type Props = {
+  comments: Comment[];
+};
+
+export const CommentList: React.FC<Props> = ({ comments }) => {
+  return (
+    <div className="CommentList">
+      {comments.map(comment => (
+        <CommentInfo comment={comment} key={comment.id} />
+      ))}
+    </div>
+  );
+};

src/components/PostInfo/PostInfo.scss

@@ -1 +1,16 @@
-// add styles here
+.PostInfo {
+  margin: 10px auto;
+  width: 90%;
+  border: 1px solid #000;
+  border-radius: 8px;
+  background-color: lightgray;
+  padding: 1em;
+
+  &__title {
+    margin: 0;
+  }
+
+  &__header {
+    margin-bottom: 1em;
+  }
+}

src/components/PostInfo/PostInfo.tsx

@@ -1,3 +1,36 @@
-import React from 'react';
+import { Post } from '../../types/Post';
+import { UserInfo } from '../UserInfo';
+import { CommentList } from '../CommentList';
+import './PostInfo.scss';
 
-export const PostInfo: React.FC = () => <>Put the post here</>;
+type Props = {
+  post: Post;
+};
+
+export const PostInfo = ({ post: { title, body, user, comments } }: Props) => {
+  const commentsElement = comments.length ? (
+    <CommentList comments={comments} />
+  ) : (
+    <b data-cy="NoCommentsMessage">No comments yet</b>
+  );
+
+  return (
+    <div className="PostInfo">
+      <div className="PostInfo__header">
+        <h3 className="PostInfo__title">{title}</h3>
+
+        <p>
+          {' Posted by '}
+
+          {user && <UserInfo user={user} />}
+        </p>
+      </div>
+
+      <p className="PostInfo__body">{body}</p>
+
+      <hr />
+
+      {commentsElement}
+    </div>
+  );
+};

src/components/PostList/PostList.tsx

@@ -1,3 +1,17 @@
 import React from 'react';
+import { Post } from '../../types/Post';
+import { PostInfo } from '../PostInfo';
 
-export const PostList: React.FC = () => <>Put the list here</>;
+type Props = {
+  posts: Post[];
+};
+
+export const PostList: React.FC<Props> = ({ posts }) => {
+  return (
+    <div className="PostList">
+      {posts.map(post => (
+        <PostInfo post={post} key={post.id} />
+      ))}
+    </div>
+  );
+};

src/components/UserInfo/UserInfo.scss

@@ -1 +1,3 @@
-// add styles here
+.UserInfo {
+  font-weight: bold;
+}

src/components/UserInfo/UserInfo.tsx

@@ -1,3 +1,15 @@
 import React from 'react';
+import { User } from '../../types/User';
+import './UserInfo.scss';
 
-export const UserInfo: React.FC = () => <>Put the user here</>;
+type Props = {
+  user: User;
+};
+
+export const UserInfo: React.FC<Props> = ({ user: { email, name } }) => {
+  return (
+    <a className="UserInfo" href={`mailto:${email}`}>
+      {name}
+    </a>
+  );
+};

src/types/Comment.ts

@@ -0,0 +1,7 @@
+export interface Comment {
+  postId: number;
+  id: number;
+  name: string;
+  email: string;
+  body: string;
+}

src/types/IDGenericFunc.ts

@@ -0,0 +1,3 @@
+export interface IDGenericFunc {
+  id: number;
+}

src/types/Post.ts

@@ -0,0 +1,11 @@
+import { User } from './User';
+import { Comment } from './Comment';
+
+export interface Post {
+  userId: number;
+  id: number;
+  title: string;
+  body: string;
+  user: User | null;
+  comments: Comment[];
+}

src/types/User.ts

@@ -0,0 +1,6 @@
+export interface User {
+  id: number;
+  name: string;
+  username: string;
+  email: string;
+}