From 631bd9ab38f9fc232f851fcb82121e258d729d11 Mon Sep 17 00:00:00 2001
From: Lefteris Karapetsas <lefteris@refu.co>
Date: Mon, 5 Jan 2015 16:37:43 +0100
Subject: [PATCH] Fix for sol scanner where empty multiline comment became
 Natspec comment

---
 libsolidity/Scanner.cpp  | 23 ++++++++++++++++-------
 libsolidity/Scanner.h    |  1 +
 test/SolidityScanner.cpp |  7 +++++++
 3 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/libsolidity/Scanner.cpp b/libsolidity/Scanner.cpp
index f22e69bc8..1f700d8b1 100644
--- a/libsolidity/Scanner.cpp
+++ b/libsolidity/Scanner.cpp
@@ -285,8 +285,6 @@ Token::Value Scanner::scanMultiLineDocComment()
 	bool endFound = false;
 	bool charsAdded = false;
 
-	advance(); //consume the last '*' at /**
-	skipWhitespaceExceptLF();
 	while (!isSourcePastEndOfInput())
 	{
 		//handle newlines in multline comments
@@ -354,11 +352,22 @@ Token::Value Scanner::scanSlash()
 			return Token::WHITESPACE;
 		else if (m_char == '*')
 		{
-			Token::Value comment;
-			m_nextSkippedComment.location.start = firstSlashPosition;
-			comment = scanMultiLineDocComment();
-			m_nextSkippedComment.location.end = getSourcePos();
-			m_nextSkippedComment.token = comment;
+			advance(); //consume the last '*' at /**
+			skipWhitespaceExceptLF();
+
+			// special case of a closed normal multiline comment
+			if (!m_source.isPastEndOfInput() && m_source.get(0) == '/')
+			{
+				advance(); //skip the closing slash
+			}
+			else // we actually have a multiline documentation comment
+			{
+				Token::Value comment;
+				m_nextSkippedComment.location.start = firstSlashPosition;
+				comment = scanMultiLineDocComment();
+				m_nextSkippedComment.location.end = getSourcePos();
+				m_nextSkippedComment.token = comment;
+			}
 			return Token::WHITESPACE;
 		}
 		else
diff --git a/libsolidity/Scanner.h b/libsolidity/Scanner.h
index 5b90a94eb..d93b79df0 100644
--- a/libsolidity/Scanner.h
+++ b/libsolidity/Scanner.h
@@ -119,6 +119,7 @@ public:
 	{
 		return m_currentToken.token;
 	}
+
 	Location getCurrentLocation() const { return m_currentToken.location; }
 	std::string const& getCurrentLiteral() const { return m_currentToken.literal; }
 	///@}
diff --git a/test/SolidityScanner.cpp b/test/SolidityScanner.cpp
index 355ea9e22..b7942d293 100644
--- a/test/SolidityScanner.cpp
+++ b/test/SolidityScanner.cpp
@@ -227,6 +227,13 @@ BOOST_AUTO_TEST_CASE(documentation_comment_before_eos)
 	BOOST_CHECK_EQUAL(scanner.getCurrentCommentLiteral(), "");
 }
 
+BOOST_AUTO_TEST_CASE(empty_multiline_comment)
+{
+	Scanner scanner(CharStream("/**/"));
+	BOOST_CHECK_EQUAL(scanner.getCurrentToken(), Token::EOS);
+	BOOST_CHECK_EQUAL(scanner.getCurrentCommentLiteral(), "");
+}
+
 BOOST_AUTO_TEST_CASE(empty_multiline_documentation_comment_before_eos)
 {
 	Scanner scanner(CharStream("/***/"));