set up jest for unit tests

Author: aurelticot

jest.config.js

@@ -0,0 +1,10 @@
+module.exports = {
+  roots: ["<rootDir>/src"],
+  testMatch: [
+    "**/__tests__/**/*.+(ts|tsx|js)",
+    "**/?(*.)+(spec|test).+(ts|tsx|js)",
+  ],
+  transform: {
+    "^.+\\.(ts|tsx)$": "ts-jest",
+  },
+};