fix corner case in `evaluate` (#3388)

fixes #3387

1 files changed, 2 insertions, 4 deletions

diff --git a/lib/compress.js b/lib/compress.js
index a7585a60..1a1b64f9 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2553,9 +2553,6 @@ merge(Compressor.prototype, {
             return this.tail_node().is_string(compressor);
         });
         def(AST_String, return_true);
-        def(AST_Sub, function(compressor) {
-            return this.expression.is_string(compressor) && this.property instanceof AST_Number;
-        });
         def(AST_SymbolRef, function(compressor) {
             var fixed = this.fixed_value();
             if (!fixed) return false;
@@ -2994,7 +2991,8 @@ merge(Compressor.prototype, {
                     val = global_objs[exp.name];
                 } else {
                     val = exp._eval(compressor, cached, depth + 1);
-                    if (!val || val === exp || !HOP(val, key)) return this;
+                    if (!val || val === exp) return this;
+                    if (typeof val == "object" && !HOP(val, key)) return this;
                     if (typeof val == "function") switch (key) {
                       case "name":
                         return val.node.name ? val.node.name.name : "";