From 432795724aede561049fa165d6de5779839630f9 Mon Sep 17 00:00:00 2001
From: cjihrig <cjihrig@gmail.com>
Date: Sun, 6 Dec 2015 00:17:26 -0500
Subject: [PATCH] assert: handle class constructors in throws()

Currently, if a class constructor is passed as the expected value
to throws(), and a match is not received, the code falls through
to the validation function case, which uses fn.prototype.call().
Class constructors must be called with new, so this throws a
TypeError. This commit adds a try...catch, which handles the
thrown error.
---
 lib/assert.js                |  8 +++++++-
 test/parallel/test-assert.js | 16 ++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/lib/assert.js b/lib/assert.js
index f8e4920cf38959..f8d8fc63da6d5e 100644
--- a/lib/assert.js
+++ b/lib/assert.js
@@ -278,7 +278,13 @@ function expectedException(actual, expected) {
     // Ignore.  The instanceof check doesn't work for arrow functions.
   }
 
-  return expected.call({}, actual) === true;
+  try {
+    return expected.call({}, actual) === true;
+  } catch (e) {
+    // Ignore. If expected is a class constructor, an error will be thrown
+  }
+
+  return false;
 }
 
 function _throws(shouldThrow, block, expected, message) {
diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js
index 0b300e737b367d..25ba94ef6c2fc5 100644
--- a/test/parallel/test-assert.js
+++ b/test/parallel/test-assert.js
@@ -334,6 +334,22 @@ try {
 }
 assert.ok(threw, 'wrong constructor validation');
 
+// Validate that a class constructor works with throws()
+threw = false;
+
+try {
+  const ClassError = class {};
+
+  assert.throws(() => {
+    throw new RangeError();
+  }, ClassError);
+} catch (e) {
+  assert(e instanceof RangeError);
+  threw = true;
+}
+
+assert.ok(threw, 'wrong constructor validation');
+
 // use a RegExp to validate error message
 a.throws(makeBlock(thrower, TypeError), /test/);