Fix #105: property comparison to undefined is not always safe

2013-01-23 23:52:04 -05:00
parent 297af47c89
commit 522566ea80
2 changed files with 19 additions and 1 deletions
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1739,7 +1739,8 @@ merge(Compressor.prototype, {
            if (self.left instanceof AST_String
                && self.left.value == "undefined"
                && self.right instanceof AST_UnaryPrefix
-                && self.right.operator == "typeof") {
+                && self.right.operator == "typeof"
+                && compressor.option("unsafe")) {
                if (!(self.right.expression instanceof AST_SymbolRef)
                    || !self.right.expression.undeclared()) {
                    self.left = self.right.expression;