From dc07891c9bd2dbab2bfd7da0b7664d70132a29fb Mon Sep 17 00:00:00 2001
From: Kabir Shah <iamkbrsh@gmail.com>
Date: Sun, 28 Apr 2019 00:24:05 -0700
Subject: [PATCH] add support for empty attribute values

---
 packages/moon/dist/moon.js                | 2 +-
 packages/moon/dist/moon.min.js            | 2 +-
 packages/moon/src/compiler/lexer/lexer.js | 4 +++-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/packages/moon/dist/moon.js b/packages/moon/dist/moon.js
index bf253606..5d958662 100644
--- a/packages/moon/dist/moon.js
+++ b/packages/moon/dist/moon.js
@@ -274,7 +274,7 @@
 					} else {
 						// Store the key/value pair using the matched value or
 						// expression.
-						attributes[attributeKey] = attributeExpression === undefined ? attributeValue : scopeExpression(attributeExpression); // Add a wrapper function for events.
+						attributes[attributeKey] = attributeExpression === undefined ? attributeValue === undefined ? "\"\"" : attributeValue : scopeExpression(attributeExpression); // Add a wrapper function for events.
 
 						if (attributeKey[0] === "@") {
 							attributes[attributeKey] = "function($event){" + attributes[attributeKey] + "}";
diff --git a/packages/moon/dist/moon.min.js b/packages/moon/dist/moon.min.js
index b1b99da5..f17233d8 100644
--- a/packages/moon/dist/moon.min.js
+++ b/packages/moon/dist/moon.min.js
@@ -4,4 +4,4 @@
  * Released under the MIT License
  * https://kbrsh.github.io/moon
  */
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\ No newline at end of file
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diff --git a/packages/moon/src/compiler/lexer/lexer.js b/packages/moon/src/compiler/lexer/lexer.js
index 0ef43c23..8761d4df 100644
--- a/packages/moon/src/compiler/lexer/lexer.js
+++ b/packages/moon/src/compiler/lexer/lexer.js
@@ -232,7 +232,9 @@ export function lex(input) {
 					// expression.
 					attributes[attributeKey] =
 						attributeExpression === undefined ?
-							attributeValue :
+							attributeValue === undefined ?
+								"\"\"" :
+								attributeValue :
 							scopeExpression(attributeExpression);
 
 					// Add a wrapper function for events.