From 88f3160c37e26258d0fbac284380e68113be4f38 Mon Sep 17 00:00:00 2001
From: Fedor Indutny <fedor@indutny.com>
Date: Mon, 20 Apr 2015 17:06:24 +0200
Subject: [PATCH] lib: do not render `undefined`

---
 lib/bemhtml/runtime/index.js |  2 ++
 test/api-test.js             | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/bemhtml/runtime/index.js b/lib/bemhtml/runtime/index.js
index 8719f740..bd4305dd 100644
--- a/lib/bemhtml/runtime/index.js
+++ b/lib/bemhtml/runtime/index.js
@@ -136,6 +136,8 @@ BEMHTML.prototype.runMany = function runMany(arr) {
 };
 
 BEMHTML.prototype.runOne = function runOne(context) {
+  if (context === undefined)
+    return '';
   if (utils.isSimple(context))
     return context + '';
 
diff --git a/test/api-test.js b/test/api-test.js
index 9655487b..abc4d464 100644
--- a/test/api-test.js
+++ b/test/api-test.js
@@ -200,4 +200,14 @@ describe('BEMHTML compiler', function() {
     }, '<div class="b2"><div class="b1"><div class="b1__e1"></div></div>' +
        '<div class="b2__e1"></div></div>');
   });
+
+  it('should not render `undefined`', function () {
+    test(function() {
+    }, [
+      undefined,
+      undefined,
+      { block: 'b1' },
+      undefined
+    ], '<div class="b1"></div>');
+  });
 });