Adding a Step to Your Github Action.md

Let's start by adding a build step after installing our dependencies and before running our test.

Building the application is a verification step in-and-of itself since we're using TypeScript. (I'll leave it as an exercise to the reader if you want to run some other type checker like tsc, but this gets the jobs done.)

name: Unit Tests

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  build-and-test:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout respository
        uses: actions/checkout@v3
      - name: Setup Node
        uses: actions/setup-node@v3
      - run: npm ci
        name: Install modules from npm
      - run: npm run build
        name: Build the application
      - run: npm test
        name: Run the tests

You'll notice that I also named the steps. This is totally optional. I like it, but it really doesn't matter much.

(No, I don't know what to do about the inconsistent capitalization.)

Adding a Second Job

What if we want build and test to run in parallel? We could try something like this:

name: Unit Tests

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout respository
        uses: actions/checkout@v3
      - name: Setup Node
        uses: actions/setup-node@v3
      - run: npm ci
        name: Install modules from npm
      - run: npm test
        name: Run the tests
  build:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout respository
        uses: actions/checkout@v3
      - name: Setup Node
        uses: actions/setup-node@v3
      - run: npm ci
        name: Install modules from npm
      - run: npm run build
        name: Build the application

You'll now have to jobs running in parallel:

There seems to be some amount of duplication though, right? Part of this is because they're running in parallel. You can actually see this in the Actions tab in your repository:

It doesn't look like much, but trust me, we're running in parallel. That said, we're still downloading and installing our assets twice.