Environment work, and start of testing

chapter05/package.json

@@ -94,6 +94,7 @@
         "flow-coverage-report": "^0.5.0",
         "flow-remove-types": "^1.2.3",
         "flow-typed": "^2.4.0",
+        "jest": "^23.0.1",
         "nodemon": "^1.17.5",
         "prettier": "^1.11.1"
     }

chapter05/src/show_env.js

@@ -0,0 +1,13 @@
+// flow()
+"use strict";
+
+const dotenv = require("dotenv");
+
+console.log(process.env);
+
+const dev = process.env.NODE_ENV || "development";
+const isDev = dev === "development";
+
+if (isDev) {
+    dotenv.load();
+}