From 3aabf88c0bcfeaeb398ae0d26c90c7c6267ec017 Mon Sep 17 00:00:00 2001
From: Jean-Louis GUENEGO <jlguenego@gmail.com>
Date: Sat, 23 Sep 2017 12:50:55 +0200
Subject: [PATCH] issue 2316 mangle and reserved

---
 lib/scope.js             |  3 +++
 test/compress/harmony.js | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/lib/scope.js b/lib/scope.js
index de35688e..48f4f3cb 100644
--- a/lib/scope.js
+++ b/lib/scope.js
@@ -549,6 +549,9 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
         var mangle_with_block_scope =
             (!options.ie8 && node instanceof AST_SymbolCatch) ||
             node instanceof AST_SymbolBlockDeclaration;
+        if (options.reserved.indexOf(node.name) >= 0) {
+            mangle_with_block_scope = false;
+        }
         if (mangle_with_block_scope) {
             to_mangle.push(node.definition());
             return;
diff --git a/test/compress/harmony.js b/test/compress/harmony.js
index 6078dd98..87cadebf 100644
--- a/test/compress/harmony.js
+++ b/test/compress/harmony.js
@@ -804,3 +804,21 @@ object_spread_of_sequence: {
         console.log({ ...o || o });
     }
 }
+
+// issue 2316
+class_name_can_be_preserved_with_reserved: {
+    mangle = {
+        reserved: ['Foo']
+    }
+    input: {
+        function x() {
+            class Foo {};
+            Foo.bar;
+            class Bar {};
+            Bar.foo;
+        }
+    }
+    expect: {
+        function x(){class Foo{}Foo.bar;class o{}o.foo}
+    }
+}
\ No newline at end of file