Create a TypeScript project

Sean Johnson — Wed, 09 Nov 2022 18:03:22 +0000

Creating a TypeScript project is easy!

Let's get up and running with build and testing scripts!

You will need a few things first:

Install Node.js from nodejs.org.
Install an editor, for example Visual Studio Code from code.visualstudio.com
Open a terminal, and get ready!

Create your project folder

Create a folder with your project's name in [[Project Name]].

NOTE: Node.js convention is to use kebab-case. All letters are lower case, and dashes are used for spaces.

Run the following command:

mkdir [[Project Name]]

Open with an Editor

The following example is for Visual Studio Code. It will likely be similar for other editors.

Open your folder in Visual Studio Code. Open Visual Studio Code, then navigate to File -> Open Folder....

Alternatively, if you have the shortcut set up, you can run the following command:

code [[Project Name]]

Once in the editor, open the Integrated Terminal to continue. Navigate to View -> Terminal, or use the Keyboard Shortcut Ctrl + ` or Cmd + `.

Continue in the system terminal

Alternatively, change directory into the folder in the current terminal:

cd [[Project Name]]

Install Dependencies

Create your package.json, which stores NPM configuration.

NOTE: When prompted, it is HIGHLY recommended to start with version 0.0.0 or 0.0.1.

This implies that the project is in development. Starting with 1.0.0 implies the project is stable.

Run the following command:

npm init

Install TypeScript and Jest as "devDependencies" in package.json. This will also create a package-lock.json file, which stores specific package version information.

Run the following command:

npm i -D typescript jest ts-jest @types/jest

Configure TypeScript

Creates your tsconfig.json file, which stores TypeScript configuration.

Run the following command:

npx tsc --init

Creates your src/index.ts file.

Run the following commands:

mkdir src
touch ./src/index.ts

In tsconfig.json, update the following "compilerOptions". This configures TypeScript to use your source files, and generate all of the necessary declaration and map files. It also enabled ES Modules.

  "module": "ESNext",
  "rootDir": "./src",
  "moduleResolution": "node",
  "declaration": true,
  "declarationMap": true,
  "sourceMap": true,
  "outDir": "./dist",

In package.json, create the following properties. This configures your package to use the TypeScript generated files. It also enabled ES Modules.

  "type": "module",
  "main": "dist/index.js",
  "types": "dist/index.d.ts",

Configure Scripts

In package.json, create the following "scripts". These are common scripts for building and testing.

  "scripts": {
    "test": "jest",
    "start": "tsc --watch",
    "build": "tsc",
    "clean": "tsc --build --clean",
    "prepublishOnly": "tsc --build --clean && tsc"
  }

In package.json, add the following section. This tells Jest how to find and run your TypeScript tests.

  "jest": {
    "preset": "ts-jest",
    "testPathIgnorePatterns": [
      "<rootDir>/dist/"
    ]
  }

Configure Git

Create your Git configuration. It is important to check in only source files.

Run the following commands:

git init
touch .gitignore

Add the following to .gitignore. This will prevent checking in TypeScript generated files.

node_modules/
dist/

Configure NPM publish

Create your NPM publish configuration. It is important to publish BOTH source files, and TypeScript generated files.

Run the following command:

touch .npmignore

Add the following to .npmignore. This will prevent checking in unnecessary files.

NOTE: Do not include dist/ or src/ in your .npmignore file.

tsconfig.json
.gitignore
.npmignore

Forem: Sean Johnson

Create a TypeScript project

Create your project folder

Open with an Editor

Continue in the system terminal

Install Dependencies

Configure TypeScript

Configure Scripts

Configure Git

Configure NPM publish