🛠 Add postinstall script to check node version

README.md

@@ -29,4 +29,8 @@ Write your solution in `src/index.js`
 1. Open [rs app](https://app.rs.school) and login
 2. Go to [submit task page](https://app.rs.school/course/submit-task?course=rs-2019-q3)
 3. Select your task (morse-decoder)
-4. Press the submit button and enjoy 
+4. Press the submit button and enjoy
+
+### Notes
+1. We recommend you to use nodejs of version 10 or lower. If you using any of features that does not supported by node v10, score won't be submitted.
+2. Please be sure that each of your test in limit of 30sec.

package.json

@@ -4,7 +4,11 @@
   "description": "Morse code decoder",
   "main": "test.js",
   "scripts": {
-    "test": "mocha test.js"
+    "test": "mocha test.js",
+    "postinstall": "node postinstall.js"
+  },
+  "engines": {
+    "node": "<=10"
   },
   "repository": {
     "type": "git",
@@ -19,5 +23,9 @@
   "devDependencies": {
     "chai": "^4.2.0",
     "mocha": "^6.2.0"
+  },
+  "dependencies": {
+    "colors": "^1.4.0",
+    "semver": "^6.3.0"
   }
 }

postinstall.js

@@ -0,0 +1,13 @@
+const semver = require('semver');
+const colors = require('colors/safe');
+
+const { engines: { node: nodeVersion }} = require('./package');
+
+if (!semver.satisfies(process.version, nodeVersion)) {
+  process.emitWarning(
+    colors.red(`
+      For this task we are strictly recomend you to use node ${nodeVersion}.
+      Now you are using node ${process.version}, if you are using any of features that not supported by node ${nodeVersion}, score won't be submitted
+    `)
+  );
+}