From e51fb90a6db53588ab2b884e4309d4eea9e37bbd Mon Sep 17 00:00:00 2001
From: Anatoli Papirovski <apapirovski@mac.com>
Date: Fri, 8 Dec 2017 16:06:02 -0500
Subject: [PATCH] tools: prefer common.expectsError in tests

Add lint rule to validate that common.expectsError(fn, err) is being
used instead of assert.throws(fn, common.expectsError(err));

PR-URL: https://github.com/nodejs/node/pull/17557
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
---
 test/.eslintrc.yaml                           |  1 +
 .../test-eslint-prefer-common-expectserror.js | 27 +++++++++++++++++++
 .../prefer-common-expectserror.js             | 21 +++++++++++++++
 3 files changed, 49 insertions(+)
 create mode 100644 test/parallel/test-eslint-prefer-common-expectserror.js
 create mode 100644 tools/eslint-rules/prefer-common-expectserror.js

diff --git a/test/.eslintrc.yaml b/test/.eslintrc.yaml
index aa320996aa4b16..7a5d002e1b51e8 100644
--- a/test/.eslintrc.yaml
+++ b/test/.eslintrc.yaml
@@ -10,6 +10,7 @@ rules:
   # Custom rules in tools/eslint-rules
   prefer-assert-iferror: error
   prefer-assert-methods: error
+  prefer-common-expectserror: error
   prefer-common-mustnotcall: error
   crypto-check: error
   inspector-check: error
diff --git a/test/parallel/test-eslint-prefer-common-expectserror.js b/test/parallel/test-eslint-prefer-common-expectserror.js
new file mode 100644
index 00000000000000..16ce66bc24e644
--- /dev/null
+++ b/test/parallel/test-eslint-prefer-common-expectserror.js
@@ -0,0 +1,27 @@
+'use strict';
+
+require('../common');
+
+const RuleTester = require('../../tools/eslint').RuleTester;
+const rule = require('../../tools/eslint-rules/prefer-common-expectserror');
+
+const message = 'Please use common.expectsError(fn, err) instead of ' +
+                'assert.throws(fn, common.expectsError(err)).';
+
+new RuleTester().run('prefer-common-expectserror', rule, {
+  valid: [
+    'assert.throws(fn, /[a-z]/)',
+    'assert.throws(function () {}, function() {})',
+    'common.expectsError(function() {}, err)'
+  ],
+  invalid: [
+    {
+      code: 'assert.throws(function() {}, common.expectsError(err))',
+      errors: [{ message }]
+    },
+    {
+      code: 'assert.throws(fn, common.expectsError(err))',
+      errors: [{ message }]
+    }
+  ]
+});
diff --git a/tools/eslint-rules/prefer-common-expectserror.js b/tools/eslint-rules/prefer-common-expectserror.js
new file mode 100644
index 00000000000000..f33241697a68ef
--- /dev/null
+++ b/tools/eslint-rules/prefer-common-expectserror.js
@@ -0,0 +1,21 @@
+'use strict';
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+const msg = 'Please use common.expectsError(fn, err) instead of ' +
+            'assert.throws(fn, common.expectsError(err)).';
+
+const astSelector =
+  'CallExpression[arguments.length=2]' +
+                '[callee.object.name="assert"]' +
+                '[callee.property.name="throws"]' +
+                '[arguments.1.callee.object.name="common"]' +
+                '[arguments.1.callee.property.name="expectsError"]';
+
+module.exports = function(context) {
+  return {
+    [astSelector]: (node) => context.report(node, msg)
+  };
+};