diff --git a/pglab/SqlSyntaxHighlighter.cpp b/pglab/SqlSyntaxHighlighter.cpp
index d61b08e..e5d0f11 100644
--- a/pglab/SqlSyntaxHighlighter.cpp
+++ b/pglab/SqlSyntaxHighlighter.cpp
@@ -46,7 +46,7 @@ void SqlSyntaxHighlighter::highlightBlock(const QString &text)
 	int startpos, length;
 	BasicTokenType tokentype;
 	QString s;
-	while (lexer.nextBasicToken(startpos, length, tokentype, s)) {
+	while (lexer.nextBasicToken(startpos, length, tokentype, s) && tokentype != BasicTokenType::End) {
 		switch (tokentype) {
 		case BasicTokenType::None:
 		case BasicTokenType::End: // End of input