test(client): initial Jest + RTL setup

.github/workflows/tests.yml

@@ -0,0 +1,39 @@
+name: Tests
+
+on:
+  push:
+    branches:
+      - main
+      - beta
+      - next
+  pull_request:
+    branches:
+      - main
+      - beta
+      - next
+
+jobs:
+  types:
+    name: "Types"
+    runs-on: ubuntu-latest
+    steps:
+      - name: Init
+        uses: actions/checkout@v2
+      - name: Use Node.js
+        uses: actions/setup-node@v1
+      - name: Install dependencies
+        uses: bahmutov/npm-install@v1
+      - name: Check types
+        run: npm run test:types
+  tests:
+    name: "Integration Tests"
+    runs-on: ubuntu-latest
+    steps:
+      - name: Init
+        uses: actions/checkout@v2
+      - name: Use Node.js
+        uses: actions/setup-node@v1
+      - name: Install dependencies
+        uses: bahmutov/npm-install@v1
+      - name: Run tests
+        run: npm test -- --ci

config/babel.config.js

@@ -18,5 +18,16 @@ module.exports = {
       test: ["../src/server/pages/**"],
       presets: ["preact"],
     },
+    {
+      test: ["../src/**/*.test.js"],
+      presets: [
+        [
+          "@babel/preset-react",
+          {
+            runtime: "automatic",
+          },
+        ],
+      ],
+    },
   ],
 }

config/jest-setup.js

@@ -0,0 +1,2 @@
+import "@testing-library/jest-dom"
+import "whatwg-fetch"

config/jest.config.js

@@ -0,0 +1,8 @@
+module.exports = {
+  transform: {
+    "\\.js$": ["babel-jest", { configFile: "./config/babel.config.js" }],
+  },
+  roots: ["../src"],
+  setupFilesAfterEnv: ["./jest-setup.js"],
+  testMatch: ["**/*.test.js"],
+}