From 316245ee12ec73427b5cd9dc9125acbf22b87fb3 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Sun, 13 Feb 2022 00:22:34 +0000
Subject: [PATCH] fix corner case in `merge_vars` (#5353)

fixes #5352
---
 lib/compress.js          | 19 ++++++++++++++++++-
 test/compress/classes.js | 26 ++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/lib/compress.js b/lib/compress.js
index a7b6397274..b0a85dddad 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -6029,7 +6029,7 @@ Compressor.prototype.compress = function(node) {
             if (node instanceof AST_Call) {
                 var exp = node.expression;
                 var tail = exp.tail_node();
-                if (!is_lambda(tail)) {
+                if (!(tail instanceof AST_LambdaExpression)) {
                     descend();
                     return mark_expression(exp);
                 }
@@ -6042,6 +6042,23 @@ Compressor.prototype.compress = function(node) {
                 tail.walk(tw);
                 return true;
             }
+            if (node instanceof AST_Class) {
+                if (node.name) node.name.walk(tw);
+                if (node.extends) node.extends.walk(tw);
+                node.properties.filter(function(prop) {
+                    if (prop.key instanceof AST_Node) prop.key.walk(tw);
+                    return prop.value;
+                }).forEach(function(prop) {
+                    if (prop.static) {
+                        prop.value.walk(tw);
+                    } else {
+                        push(tw);
+                        prop.value.walk(tw);
+                        pop(tw);
+                    }
+                });
+                return true;
+            }
             if (node instanceof AST_Conditional) {
                 walk_cond(node.condition, node.consequent, node.alternative);
                 return true;
diff --git a/test/compress/classes.js b/test/compress/classes.js
index 4471663d7c..2713a24831 100644
--- a/test/compress/classes.js
+++ b/test/compress/classes.js
@@ -2476,3 +2476,29 @@ issue_5322: {
     expect_stdout: "42"
     node_version: ">=12"
 }
+
+issue_5352: {
+    options = {
+        merge_vars: true,
+    }
+    input: {
+        function f(a) {
+            var b;
+            new class {
+                [b = console.log(a)] = b;
+            }(a.p);
+        }
+        f("PASS");
+    }
+    expect: {
+        function f(a) {
+            var b;
+            new class {
+                [b = console.log(a)] = b;
+            }(a.p);
+        }
+        f("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}