tools: add number-isnan rule

PR-URL: https://github.com/nodejs/node/pull/17556
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/test/parallel/test-eslint-number-isnan.js b/test/parallel/test-eslint-number-isnan.js
new file mode 100644
index 0000000000..deeac48bcc
--- /dev/null
+++ b/test/parallel/test-eslint-number-isnan.js
@@ -0,0 +1,20 @@
+'use strict';
+
+require('../common');
+
+const RuleTester = require('../../tools/eslint').RuleTester;
+const rule = require('../../tools/eslint-rules/number-isnan');
+
+const message = 'Please use Number.isNaN instead of the global isNaN function';
+
+new RuleTester().run('number-isnan', rule, {
+  valid: [
+    'Number.isNaN()'
+  ],
+  invalid: [
+    {
+      code: 'isNaN()',
+      errors: [{ message }]
+    }
+  ]
+});