Added remaining exercises

Author: mattpocock

README.md

@@ -10,8 +10,6 @@ yarn exercise 01
 
 ## How to take the course
 
-First, start up the [video on YouTube](TODO).
-
 You'll notice that the course is split into exercises. Each exercise is split into a `*.problem.ts` and a `*.solution.ts`.
 
 To take an exercise:
@@ -23,7 +21,7 @@ The `exercise` script will run TypeScript typechecks and a test suite on the exe
 
 This course encourages **active, exploratory learning**. In the video, I'll explain a problem, and **you'll be asked to try to find a solution**. To attempt a solution, you'll need to:
 
-1. Check out [Zod's docs](https://github.com/colinhacks/zod)
+1. Check out [TypeScript's docs](https://www.typescriptlang.org/docs/handbook/intro.html)
 2. Try to find something that looks relevant.
 3. Give it a go to see if it solves the problem.
 

package.json

@@ -3,7 +3,7 @@
   "version": "1.0.0",
   "main": "index.js",
   "author": "Matt Pocock <mattpocockvoice@gmail.com>",
-  "license": "GPT-3",
+  "license": "MIT",
   "devDependencies": {
     "@types/node": "^18.6.5",
     "chokidar": "^3.5.3",
@@ -13,7 +13,9 @@
   },
   "scripts": {
     "exercise": "node scripts/exercise.js",
-    "solution": "SOLUTION=true node scripts/exercise.js"
+    "e": "yarn exercise",
+    "solution": "SOLUTION=true node scripts/exercise.js",
+    "s": "yarn solution"
   },
   "dependencies": {
     "@types/express": "^4.17.13",

scripts/exercise.js

@@ -15,15 +15,15 @@ if (!exercise) {
 
 const allExercises = fs.readdirSync(srcPath);
 
-let suffix = ".problem.ts";
+let pathIndicator = ".problem.";
 
 if (process.env.SOLUTION) {
-  suffix = ".solution.ts";
+  pathIndicator = ".solution.";
 }
 
 const exercisePath = allExercises.find(
   (exercisePath) =>
-    exercisePath.startsWith(exercise) && exercisePath.endsWith(suffix),
+    exercisePath.startsWith(exercise) && exercisePath.includes(pathIndicator),
 );
 
 if (!exercisePath) {
@@ -35,12 +35,17 @@ const exerciseFile = path.resolve(srcPath, exercisePath);
 
 // One-liner for current directory
 chokidar.watch(exerciseFile).on("all", (event, path) => {
+  const fileContents = fs.readFileSync(exerciseFile, "utf8");
+
+  const containsVitest = fileContents.includes("vitest");
   try {
     console.clear();
-    console.log("Running tests...");
-    execSync(`vitest run ${exerciseFile} --passWithNoTests`, {
-      stdio: "inherit",
-    });
+    if (containsVitest) {
+      console.log("Running tests...");
+      execSync(`vitest run ${exerciseFile} --passWithNoTests`, {
+        stdio: "inherit",
+      });
+    }
     console.log("Checking types...");
     execSync(`tsc ${exerciseFile} --noEmit --strict`, {
       stdio: "inherit",

src/05-assigning-types-to-variables.problem.ts

@@ -0,0 +1,22 @@
+import { expect, it } from "vitest";
+
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  isAdmin: boolean;
+}
+
+/**
+ * How do we ensure that defaultUser is of type User
+ * at THIS LINE - not further down in the code?
+ */
+const defaultUser = {};
+
+const getUserId = (user: User) => {
+  return user.id;
+};
+
+it("Should get the user id", () => {
+  expect(getUserId(defaultUser)).toEqual(1);
+});

src/05-assigning-types-to-variables.solution.ts

@@ -0,0 +1,27 @@
+import { expect, it } from "vitest";
+
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  isAdmin: boolean;
+}
+
+/**
+ * How do we ensure that defaultUser is of type User
+ * at THIS LINE - not further down in the code?
+ */
+const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  isAdmin: true,
+};
+
+const getUserId = (user: User) => {
+  return user.id;
+};
+
+it("Should get the user id", () => {
+  expect(getUserId(defaultUser)).toEqual(1);
+});

src/06-unions.problem.ts

@@ -0,0 +1,20 @@
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  /**
+   * How do we ensure that role is only one of:
+   * - 'admin'
+   * - 'user'
+   * - 'super-admin'
+   */
+  role: string;
+}
+
+export const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  // @ts-expect-error
+  role: "I_SHOULD_NOT_BE_ALLOWED",
+};

src/06-unions.solution.ts

@@ -0,0 +1,20 @@
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  /**
+   * How do we ensure that role is only one of:
+   * - 'admin'
+   * - 'user'
+   * - 'super-admin'
+   */
+  role: "admin" | "user" | "super-admin";
+}
+
+export const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  // @ts-expect-error
+  role: "I_SHOULD_NOT_BE_ALLOWED",
+};

src/07-arrays.problem.ts

@@ -0,0 +1,31 @@
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  /**
+   * How do we ensure that role is only one of:
+   * - 'admin'
+   * - 'user'
+   * - 'super-admin'
+   */
+  role: "admin" | "user" | "super-admin";
+  posts: Post;
+}
+
+interface Post {
+  id: number;
+  title: string;
+}
+
+export const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  role: "admin",
+  posts: [
+    {
+      id: 1,
+      title: "How I eat so much cheese",
+    },
+  ],
+};

src/07-arrays.solution.1.ts

@@ -0,0 +1,31 @@
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  /**
+   * How do we ensure that role is only one of:
+   * - 'admin'
+   * - 'user'
+   * - 'super-admin'
+   */
+  role: "admin" | "user" | "super-admin";
+  posts: Post[];
+}
+
+interface Post {
+  id: number;
+  title: string;
+}
+
+export const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  role: "admin",
+  posts: [
+    {
+      id: 1,
+      title: "How I eat so much cheese",
+    },
+  ],
+};

src/07-arrays.solution.2.ts

@@ -0,0 +1,31 @@
+interface User {
+  id: number;
+  firstName: string;
+  lastName: string;
+  /**
+   * How do we ensure that role is only one of:
+   * - 'admin'
+   * - 'user'
+   * - 'super-admin'
+   */
+  role: "admin" | "user" | "super-admin";
+  posts: Array<Post>;
+}
+
+interface Post {
+  id: number;
+  title: string;
+}
+
+export const defaultUser: User = {
+  id: 1,
+  firstName: "Matt",
+  lastName: "Pocock",
+  role: "admin",
+  posts: [
+    {
+      id: 1,
+      title: "How I eat so much cheese",
+    },
+  ],
+};