refactor: move jest around and add code coverage

package.json

@@ -37,7 +37,6 @@
     "@types/http-proxy": "^1.17.4",
     "@types/js-yaml": "^3.12.3",
     "@types/node": "^12.12.7",
-    "@types/node-fetch": "^2.5.7",
     "@types/parcel-bundler": "^1.12.1",
     "@types/pem": "^1.9.5",
     "@types/proxy-from-env": "^1.0.1",
@@ -107,5 +106,28 @@
   ],
   "engines": {
     "node": ">= 12"
+  },
+  "jest": {
+    "transform": {
+      "^.+\\.ts$": "<rootDir>/test/node_modules/ts-jest"
+    },
+    "testEnvironment": "node",
+    "testPathIgnorePatterns": [
+      "/node_modules/",
+      "<rootDir>/lib/vscode",
+      "<rootDir>/out"
+    ],
+    "collectCoverage": true,
+    "collectCoverageFrom": [
+      "<rootDir>/src/**/*.ts"
+    ],
+    "coverageDirectory": "<rootDir>/coverage",
+    "coverageReporters": [
+      "json",
+      "text"
+    ],
+    "coveragePathIgnorePatterns": [
+      "out"
+    ]
   }
 }