ci(test coverage): add nyc and cross-env to include test coverage

BREAKING CHANGE: need to install nyc, cross-env and babel-plugin-istanbul plugins

.babelrc

@@ -2,7 +2,7 @@
   "presets": ["env"],
   "env":{
     "test":{
-      "presets":["env"]
+      "plugins": ["istanbul"]
     }
   }
 }

.gitignore

@@ -1,3 +1,10 @@
 .idea/
 node_modules/
 *.log
+
+# build
+build/
+
+# code coverage
+.nyc_output
+coverage/

package.json

@@ -4,7 +4,7 @@
   "description": "It is to locate the location of a user",
   "main": "src/index.js",
   "scripts": {
-    "test": "NODE_ENV=test ./node_modules/.bin/mocha --require babel-register --require isomorphic-fetch --require babel-polyfill tests/*.js --reporter spec||exit 0",
+    "test": "cross-env NODE_ENV=test nyc --require babel-register --require isomorphic-fetch --require babel-polyfill --reporter=lcov --reporter=text mocha ./tests/*.js",
     "clean": "rm -rf build",
     "prepublish": "npm test",
     "commit": "git-cz",
@@ -33,18 +33,21 @@
     "babel-core": "^6.26.0",
     "babel-eslint": "^8.2.1",
     "babel-loader": "^7.1.2",
+    "babel-plugin-istanbul": "^4.1.5",
     "babel-polyfill": "^6.26.0",
     "babel-preset-env": "^1.6.1",
     "babel-register": "^6.26.0",
     "chai": "^4.1.2",
     "commitizen": "^2.9.6",
+    "cross-env": "^5.1.3",
     "cz-conventional-changelog": "^2.1.0",
     "eslint": "^4.17.0",
     "eslint-config-airbnb-base": "^12.1.0",
     "eslint-plugin-import": "^2.8.0",
     "fetch-mock": "^6.0.0",
     "isomorphic-fetch": "^2.2.1",
     "mocha": "^5.0.0",
+    "nyc": "10",
     "sinon": "^4.3.0",
     "webpack": "^3.11.0",
     "webpack-dev-server": "^2.11.1"
@@ -54,6 +57,24 @@
       "path": "./node_modules/cz-conventional-changelog"
     }
   },
+  "nyc": {
+    "check-coverage": true,
+    "per-file": true,
+    "lines": 99,
+    "statements": 99,
+    "functions": 99,
+    "branches": 99,
+    "include": [
+      "src/**/*.js"
+    ],
+    "require": [
+      "babel-register",
+      "isomorphic-fetch",
+      "babel-polyfill"
+    ],
+    "sourceMap": false,
+    "instrument": false
+  },
   "dependencies": {
     "geo-amazon": "^0.2.0"
   }