Disable on CI (#116)

index.js

@@ -12,6 +12,7 @@ const isNpm = importLazy('is-npm');
 const isInstalledGlobally = importLazy('is-installed-globally');
 const boxen = importLazy('boxen');
 const xdgBasedir = importLazy('xdg-basedir');
+const isCi = importLazy('is-ci');
 const ONE_DAY = 1000 * 60 * 60 * 24;
 
 class UpdateNotifier {
@@ -37,7 +38,8 @@ class UpdateNotifier {
 		this.hasCallback = typeof options.callback === 'function';
 		this.callback = options.callback || (() => {});
 		this.disabled = 'NO_UPDATE_NOTIFIER' in process.env ||
-			process.argv.indexOf('--no-update-notifier') !== -1;
+			process.argv.indexOf('--no-update-notifier') !== -1 ||
+			isCi();
 
 		if (!this.disabled && !this.hasCallback) {
 			try {

package.json

@@ -37,6 +37,7 @@
     "chalk": "^2.0.1",
     "configstore": "^3.0.0",
     "import-lazy": "^2.1.0",
+    "is-ci": "^1.0.10",
     "is-installed-globally": "^0.1.0",
     "is-npm": "^1.0.0",
     "latest-version": "^3.0.0",
@@ -47,6 +48,7 @@
     "ava": "*",
     "clear-module": "^2.1.0",
     "fixture-stdout": "^0.2.1",
+    "mock-require": "^2.0.2",
     "strip-ansi": "^4.0.0",
     "xo": "^0.18.2"
   }

readme.md

@@ -159,6 +159,8 @@ Users of your module have the ability to opt-out of the update notifier by chang
 
 Users can also opt-out by [setting the environment variable](https://github.com/sindresorhus/guides/blob/master/set-environment-variables.md) `NO_UPDATE_NOTIFIER` with any value or by using the `--no-update-notifier` flag on a per run basis.
 
+The check is also skipped on CI automatically.
+
 
 ## About
 

test/update-notifier.js

@@ -1,5 +1,10 @@
 import fs from 'fs';
 import test from 'ava';
+import mockRequire from 'mock-require';
+
+mockRequire('is-ci', false);
+
+// eslint-disable-next-line import/first
 import updateNotifier from '..';
 
 const generateSettings = options => {