From 12985d86c2a7ae66adaf4a08fe44ac3be1f6ef14 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Fri, 23 Mar 2018 07:27:35 +0800
Subject: [PATCH] fix corner case in `hoist_props` (#3022)

fixes #3021
---
 lib/compress.js              |  3 ++-
 test/compress/hoist_props.js | 30 ++++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/lib/compress.js b/lib/compress.js
index 972341bb..03ed9e8a 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -3624,8 +3624,9 @@ merge(Compressor.prototype, {
                 var sym = node.name, def, value;
                 if (sym.scope === self
                     && (def = sym.definition()).escaped != 1
-                    && !def.single_use
+                    && !def.assignments
                     && !def.direct_access
+                    && !def.single_use
                     && !top_retain(def)
                     && (value = sym.fixed_value()) === node.value
                     && value instanceof AST_Object) {
diff --git a/test/compress/hoist_props.js b/test/compress/hoist_props.js
index 26887af2..90a7f1d8 100644
--- a/test/compress/hoist_props.js
+++ b/test/compress/hoist_props.js
@@ -686,3 +686,33 @@ undefined_key: {
     }
     expect_stdout: "3"
 }
+
+issue_3021: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        var a = 1, b = 2;
+        (function() {
+            b = a;
+            if (a++ + b--)
+                return 1;
+            return;
+            var b = {};
+        })();
+        console.log(a, b);
+    }
+    expect: {
+        var a = 1, b = 2;
+        (function() {
+            b = a;
+            if (a++ + b--)
+                return 1;
+            return;
+            var b = {};
+        })();
+        console.log(a, b);
+    }
+    expect_stdout: "2 2"
+}
-- 
2.34.1