From 9eb9758635bee8b1a30765818e46ee09e7741de5 Mon Sep 17 00:00:00 2001
From: Alexander Amosov <aamosov@avito.ru>
Date: Fri, 6 Oct 2017 14:27:43 +0300
Subject: [PATCH 1/2] Fixed issue #55 undefined attribute values are converted
 to strings

---
 index.js     | 1 +
 test/attr.js | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/index.js b/index.js
index 209f3b6..2eed790 100644
--- a/index.js
+++ b/index.js
@@ -265,6 +265,7 @@ module.exports = function (h, opts) {
     if (typeof x === 'function') return x
     else if (typeof x === 'string') return x
     else if (x && typeof x === 'object') return x
+    else if (x === null || x === undefined) return x
     else return concat('', x)
   }
 }
diff --git a/test/attr.js b/test/attr.js
index 0cd3859..21e9ae8 100644
--- a/test/attr.js
+++ b/test/attr.js
@@ -74,3 +74,9 @@ test('strange inbetween character attributes', function (t) {
   t.equal(vdom.create(tree).toString(), `<div f@o="bar" b&z="qux"></div>`)
   t.end()
 })
+
+test('null and undefined attributes', function (t) {
+  var tree = hx`<div onclick="alert(1)" onmouseenter=${undefined} onmouseleave=${null}></div>`
+  t.equal(vdom.create(tree).toString(), `<div onclick="alert(1)"></div>`)
+  t.end()
+})

From 1028609990cad895f8b015600f13f47daf151abf Mon Sep 17 00:00:00 2001
From: jjurman <jjurman@constantcontact.com>
Date: Mon, 11 Feb 2019 13:55:02 +0100
Subject: [PATCH 2/2] ignore attribute if injected value is null or undefined

---
 test/attr.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/attr.js b/test/attr.js
index 21e9ae8..d4c94c7 100644
--- a/test/attr.js
+++ b/test/attr.js
@@ -80,3 +80,33 @@ test('null and undefined attributes', function (t) {
   t.equal(vdom.create(tree).toString(), `<div onclick="alert(1)"></div>`)
   t.end()
 })
+
+test('undefined (with quotes) attribute value is evaluated', function (t) {
+  var tree = hx`<div foo='undefined'></div>`
+  t.equal(vdom.create(tree).toString(), `<div foo="undefined"></div>`)
+  t.end()
+})
+
+test('null (with quotes) attribute value is evaluated', function (t) {
+  var tree = hx`<div foo='null'></div>`
+  t.equal(vdom.create(tree).toString(), `<div foo="null"></div>`)
+  t.end()
+})
+
+test('undefined (without quotes) attribute value is evaluated', function (t) {
+  var tree = hx`<div foo=undefined></div>`
+  t.equal(vdom.create(tree).toString(), `<div foo="undefined"></div>`)
+  t.end()
+})
+
+test('null (without quotes) attribute value is evaluated', function (t) {
+  var tree = hx`<div foo=null></div>`
+  t.equal(vdom.create(tree).toString(), `<div foo="null"></div>`)
+  t.end()
+})
+
+test('null is ignored and adjacent attribute is evaluated', function (t) {
+  var tree = hx`<div foo=${null} t></div>`
+  t.equal(vdom.create(tree).toString(), `<div t="t"></div>`)
+  t.end()
+})