From 9f7d1f7ac62e80e3f7f83600d28aeeaef60d0d86 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Wed, 27 Dec 2017 16:30:57 +0800
Subject: [PATCH] fix `reduce_vars` on `AST_Destructuring` (#2672)

fixes #2669
fixes #2670
fixes #2673
---
 lib/compress.js              |  6 +++++-
 test/compress/reduce_vars.js | 41 ++++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/lib/compress.js b/lib/compress.js
index 91e3c388..44b27584 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -482,6 +482,10 @@ merge(Compressor.prototype, {
         def(AST_Arrow, mark_func_expr);
         def(AST_Assign, function(tw) {
             var node = this;
+            if (node.left instanceof AST_Destructuring) {
+                node.left.walk(suppressor);
+                return;
+            }
             if (node.operator != "=" || !(node.left instanceof AST_SymbolRef)) return;
             var d = node.left.definition();
             if (safe_to_assign(tw, d, node.right)
@@ -705,7 +709,7 @@ merge(Compressor.prototype, {
             var node = this;
             if (node.name instanceof AST_Destructuring) {
                 node.name.walk(suppressor);
-                return true;
+                return;
             }
             var d = node.name.definition();
             if (d.fixed === undefined || safe_to_assign(tw, d, node.value)) {
diff --git a/test/compress/reduce_vars.js b/test/compress/reduce_vars.js
index f04f7c75..5253026f 100644
--- a/test/compress/reduce_vars.js
+++ b/test/compress/reduce_vars.js
@@ -5446,3 +5446,44 @@ issue_2598: {
     }
     expect_stdout: "true"
 }
+
+issue_2669: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        let foo;
+        console.log(([ foo ] = [ "PASS" ]) && foo);
+    }
+    expect: {
+        let foo;
+        console.log(([ foo ] = [ "PASS" ]) && foo);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_2670: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        const obj = {};
+        obj.prop = "PASS";
+        const {prop: value} = obj;
+        console.log(value);
+    }
+    expect: {
+        const obj = {};
+        obj.prop = "PASS";
+        const {prop: value} = obj;
+        console.log(value);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}