From dec5900c421166291612afabe2832d11dde2d201 Mon Sep 17 00:00:00 2001
From: Rich Trott <rtrott@gmail.com>
Date: Fri, 4 Nov 2016 14:08:50 -0700
Subject: [PATCH] tools: add lint rule to enforce timer arguments

Add a custom ESLint rule to require that setTimeout() and setInterval()
get called with at least two arguments. This prevents omitting the
duration or interval.

PR-URL: https://github.com/nodejs/node/pull/9472
Reviewed-By: Teddy Katz <teddy.katz@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 .eslintrc                             |  1 +
 tools/eslint-rules/timer-arguments.js | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 tools/eslint-rules/timer-arguments.js

diff --git a/.eslintrc b/.eslintrc
index d2cc8ea000ac3f..34f32e59f0a626 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -124,6 +124,7 @@ rules:
   assert-fail-single-argument: 2
   assert-throws-arguments: [2, { requireTwo: false }]
   new-with-error: [2, Error, RangeError, TypeError, SyntaxError, ReferenceError]
+  timer-arguments: 2
 
 # Global scoped method and vars
 globals:
diff --git a/tools/eslint-rules/timer-arguments.js b/tools/eslint-rules/timer-arguments.js
new file mode 100644
index 00000000000000..4dd7816ff82ff2
--- /dev/null
+++ b/tools/eslint-rules/timer-arguments.js
@@ -0,0 +1,25 @@
+/**
+ * @fileoverview Require at least two arguments when calling setTimeout() or
+ * setInterval().
+ * @author Rich Trott
+ */
+'use strict';
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+function isTimer(name) {
+  return ['setTimeout', 'setInterval'].includes(name);
+}
+
+module.exports = function(context) {
+  return {
+    'CallExpression': function(node) {
+      const name = node.callee.name;
+      if (isTimer(name) && node.arguments.length < 2) {
+        context.report(node, `${name} must have at least 2 arguments`);
+      }
+    }
+  };
+};