Do not apply negate_iife optimization to `new` expression

2 files changed, 29 insertions, 0 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 2bcfcf30..1d6a943b 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -811,6 +811,11 @@ merge(Compressor.prototype, {
                 if (stat instanceof AST_SimpleStatement) {
                     stat.body = (function transform(thing) {
                         return thing.transform(new TreeTransformer(function(node){
+                            if (node instanceof AST_New
+                                && node.expression instanceof AST_Call
+                                && node.expression.expression instanceof AST_Function) {
+                                return node;
+                            }
                             if (node instanceof AST_Call && node.expression instanceof AST_Function) {
                                 return make_node(AST_UnaryPrefix, node, {
                                     operator: "!",
diff --git a/test/compress/negate-iife.js b/test/compress/negate-iife.js
index 89c3f064..20b3f56e 100644
--- a/test/compress/negate-iife.js
+++ b/test/compress/negate-iife.js
@@ -74,3 +74,27 @@ negate_iife_4: {
         }();
     }
 }
+
+negate_iife_issue_1073: {
+    options = {
+        negate_iife: true,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        new (function(a) {
+            return function Foo() {
+                this.x = a;
+                console.log(this);
+            };
+        }(7))();
+    }
+    expect: {
+        new (function(a) {
+            return function Foo() {
+                this.x = a,
+                console.log(this);
+            };
+        }(7))();
+    }
+}