From 8195a664fd83e7381d0823e01a4ea30dc28e9f0d Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Wed, 19 Jun 2024 05:15:03 +0300
Subject: [PATCH] fix corner case in `collapse_vars` (#5855)

fixes #5854
---
 lib/compress.js               |  6 +++--
 test/compress/destructured.js | 48 +++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/lib/compress.js b/lib/compress.js
index 02d68e2d384..ff5652e4ba9 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2722,8 +2722,10 @@ Compressor.prototype.compress = function(node) {
                 if (sym instanceof AST_PropAccess) return true;
                 if (check_destructured(sym)) return true;
                 return sym.match_symbol(function(node) {
-                    return node instanceof AST_SymbolRef
-                        && (lvalues.has(node.name) || read_toplevel && compressor.exposed(node.definition()));
+                    if (node instanceof AST_PropAccess) return true;
+                    if (node instanceof AST_SymbolRef) {
+                        return lvalues.has(node.name) || read_toplevel && compressor.exposed(node.definition());
+                    }
                 }, true);
 
                 function reject(node) {
diff --git a/test/compress/destructured.js b/test/compress/destructured.js
index 8b394b0ed65..a8a194d3c5c 100644
--- a/test/compress/destructured.js
+++ b/test/compress/destructured.js
@@ -3959,3 +3959,51 @@ issue_5844: {
     expect_stdout: "PASS"
     node_version: ">=6"
 }
+
+issue_5854_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            [ b[0] ] = [ "foo" ];
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            [ b[0] ] = [ "foo" ];
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5854_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            ({ p: b[0] } = { p: "foo" });
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            ({ p: b[0] } = { p: "foo" });
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}