From: Mihai Bazon <mihai@bazon.net>
Date: Sat, 17 Nov 2012 10:05:31 +0000 (+0200)
Subject: retain (1,eval) as is when it's the expression of an AST_Call
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=0d3fd2ef30d0a85edb76d6db6e9f6ef034f1cee4;p=UglifyJS.git

retain (1,eval) as is when it's the expression of an AST_Call

otherwise we change the meaning of eval from global to lexical.
---

diff --git a/lib/compress.js b/lib/compress.js
index 66375be8..7c4c910d 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1549,8 +1549,19 @@ merge(Compressor.prototype, {
     OPT(AST_Seq, function(self, compressor){
         if (!compressor.option("side_effects"))
             return self;
-        if (!self.car.has_side_effects())
-            return self.cdr;
+        if (!self.car.has_side_effects()) {
+            // we shouldn't compress (1,eval)(something) to
+            // eval(something) because that changes the meaning of
+            // eval (becomes lexical instead of global).
+            var p;
+            if (!(self.cdr instanceof AST_SymbolRef
+                  && self.cdr.name == "eval"
+                  && self.cdr.undeclared()
+                  && (p = compressor.parent()) instanceof AST_Call
+                  && p.expression === self)) {
+                return self.cdr;
+            }
+        }
         if (compressor.option("cascade")) {
             if (self.car instanceof AST_Assign
                 && !self.car.left.has_side_effects()