Fix typeof evaluation for regex and function

1 files changed, 12 insertions, 1 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 5a6adcd5..216826d6 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -625,7 +625,18 @@ merge(Compressor.prototype, {
             var e = this.expression;
             switch (this.operator) {
               case "!": return !ev(e);
-              case "typeof": return typeof ev(e);
+              case "typeof":
+                // Function would be evaluated to an array and so typeof would
+                // incorrectly return 'object'. Hence making is a special case.
+                if (e instanceof AST_Function) return typeof function(){};
+
+                e = ev(e);
+
+                // typeof <RegExp> returns "object" or "function" on different platforms
+                // so cannot evaluate reliably
+                if (e instanceof RegExp) throw def;
+
+                return typeof e;
               case "void": return void ev(e);
               case "~": return ~ev(e);
               case "-":