Add testing config.

package.json

@@ -11,7 +11,7 @@
     "build:chromium": "VITE_BROWSER=chromium vite build && web-ext build -n re-nav-chromium-{version}.zip -s build/chromium",
     "build:firefox": "VITE_BROWSER=firefox vite build && web-ext build -n re-nav-firefox-{version}.zip -s build/firefox",
     "zip-source": "git archive --format zip --output web-ext-artifacts/re-nav-source.zip HEAD",
-    "test": "xo && stylelint 'source/**/*.scss' && tsc"
+    "test": "xo && stylelint 'source/**/*.scss' && tsc && c8 ava"
   },
   "dependencies": {
     "@holllo/migration-helper": "^0.1.3",
@@ -25,18 +25,54 @@
     "@preact/preset-vite": "^2.4.0",
     "@types/babel__core": "^7.1.19",
     "@types/webextension-polyfill": "^0.9.1",
+    "ava": "^4.3.3",
+    "c8": "^7.12.0",
     "postcss": "^8.4.16",
     "sass": "^1.55.0",
     "stylelint": "^14.13.0",
     "stylelint-config-standard-scss": "^5.0.0",
     "trash-cli": "^5.0.0",
+    "ts-node": "^10.9.1",
     "typescript": "^4.8.4",
     "vite": "^3.1.4",
     "vite-plugin-web-extension": "^1.4.4",
     "web-ext": "^7.2.0",
     "xo": "^0.52.3"
   },
+  "ava": {
+    "extensions": [
+      "ts"
+    ],
+    "files": [
+      "tests/**/*.test.ts"
+    ],
+    "require": [
+      "ts-node/register"
+    ],
+    "snapshotDir": "tests/snapshots"
+  },
+  "c8": {
+    "include": [
+      "source",
+      "tests"
+    ],
+    "reportDir": "coverage",
+    "reporter": [
+      "text",
+      "html"
+    ]
+  },
   "xo": {
+    "overrides": [
+      {
+        "files": "tests/**/*.test.ts",
+        "rules": {
+          "@typescript-eslint/triple-slash-reference": "off",
+          "import/extensions": "off",
+          "no-await-in-loop": "off"
+        }
+      }
+    ],
     "prettier": true,
     "rules": {
       "@typescript-eslint/consistent-type-definitions": "off",

tsconfig.json

@@ -13,6 +13,12 @@
   },
   "include": [
     "source/**/*.ts",
+    "tests/**/*.ts",
     "vite.config.ts"
-  ]
+  ],
+  "ts-node": {
+    "compilerOptions": {
+      "module": "CommonJS"
+    }
+  }
 }