fix `dead_code` on nested `try` (#2599)

fixes #2597

1 files changed, 6 insertions, 7 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 0162fa4e..a8bcf54f 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -4751,11 +4751,7 @@ merge(Compressor.prototype, {
                 node = parent;
                 parent = compressor.parent(level++);
                 if (parent instanceof AST_Exit) {
-                    var try_node = find_try(level);
-                    if (try_node) {
-                        if (try_node.bfinally) break;
-                        if (parent instanceof AST_Throw && try_node.bcatch) break;
-                    }
+                    if (in_try(level, parent instanceof AST_Throw)) break;
                     if (self.operator == "=") return self.right;
                     return make_node(AST_Binary, self, {
                         operator: self.operator.slice(0, -1),
@@ -4787,11 +4783,14 @@ merge(Compressor.prototype, {
         }
         return self;
 
-        function find_try(level) {
+        function in_try(level, no_catch) {
             var scope = self.left.definition().scope;
             var parent;
             while ((parent = compressor.parent(level++)) !== scope) {
-                if (parent instanceof AST_Try) return parent;
+                if (parent instanceof AST_Try) {
+                    if (parent.bfinally) return true;
+                    if (no_catch && parent.bcatch) return true;
+                }
             }
         }
     });