2 files changed, 62 insertions, 6 deletions

diff --git a/src/bun.js/bindings/bindings.cpp b/src/bun.js/bindings/bindings.cpp
index be3408555..96fcde303 100644
--- a/src/bun.js/bindings/bindings.cpp
+++ b/src/bun.js/bindings/bindings.cpp
@@ -679,8 +679,8 @@ bool Bun__deepEquals(JSC__JSGlobalObject* globalObject, JSValue v1, JSValue v2,
             return false;
         }
 
-        JSC::PropertyNameArray a1(vm, PropertyNameMode::Symbols, PrivateSymbolMode::Include);
-        JSC::PropertyNameArray a2(vm, PropertyNameMode::Symbols, PrivateSymbolMode::Include);
+        JSC::PropertyNameArray a1(vm, PropertyNameMode::Symbols, PrivateSymbolMode::Exclude);
+        JSC::PropertyNameArray a2(vm, PropertyNameMode::Symbols, PrivateSymbolMode::Exclude);
         JSObject::getOwnPropertyNames(o1, globalObject, a1, DontEnumPropertiesMode::Exclude);
         JSObject::getOwnPropertyNames(o2, globalObject, a2, DontEnumPropertiesMode::Exclude);
 
@@ -753,7 +753,7 @@ bool Bun__deepEquals(JSC__JSGlobalObject* globalObject, JSValue v1, JSValue v2,
             }
 
             o1Structure->forEachProperty(vm, [&](const PropertyTableEntry& entry) -> bool {
-                if (entry.attributes() & PropertyAttribute::DontEnum) {
+                if (entry.attributes() & PropertyAttribute::DontEnum || PropertyName(entry.key()).isPrivateName()) {
                     return true;
                 }
                 count1++;
@@ -787,7 +787,7 @@ bool Bun__deepEquals(JSC__JSGlobalObject* globalObject, JSValue v1, JSValue v2,
             if (result && o2Structure->id() != o1Structure->id()) {
                 size_t remain = count1;
                 o2Structure->forEachProperty(vm, [&](const PropertyTableEntry& entry) -> bool {
-                    if (entry.attributes() & PropertyAttribute::DontEnum) {
+                    if (entry.attributes() & PropertyAttribute::DontEnum || PropertyName(entry.key()).isPrivateName()) {
                         return true;
                     }
 
@@ -815,8 +815,8 @@ bool Bun__deepEquals(JSC__JSGlobalObject* globalObject, JSValue v1, JSValue v2,
         }
     }
 
-    JSC::PropertyNameArray a1(vm, PropertyNameMode::StringsAndSymbols, PrivateSymbolMode::Include);
-    JSC::PropertyNameArray a2(vm, PropertyNameMode::StringsAndSymbols, PrivateSymbolMode::Include);
+    JSC::PropertyNameArray a1(vm, PropertyNameMode::StringsAndSymbols, PrivateSymbolMode::Exclude);
+    JSC::PropertyNameArray a2(vm, PropertyNameMode::StringsAndSymbols, PrivateSymbolMode::Exclude);
     o1->getPropertyNames(globalObject, a1, DontEnumPropertiesMode::Exclude);
     o2->getPropertyNames(globalObject, a2, DontEnumPropertiesMode::Exclude);
 
diff --git a/test/js/bun/test/expect.test.js b/test/js/bun/test/expect.test.js
index e7195d6f8..ed94b7e9a 100644
--- a/test/js/bun/test/expect.test.js
+++ b/test/js/bun/test/expect.test.js
@@ -1335,6 +1335,62 @@ describe("expect()", () => {
     expect([1, 2, 3, 4]).not.toEqual([1, 2, 3]);
   });
 
+  test("toEqual() - private class fields", () => {
+    class A {
+      #three = 3;
+      set three(value) {
+        this.#three = value;
+      }
+
+      get three() {
+        return this.#three;
+      }
+    }
+
+    class B {
+      #three = 3;
+      set three(value) {
+        this.#three = value;
+      }
+
+      get three() {
+        return this.#three;
+      }
+    }
+
+    let a1 = new A();
+    let a2 = new A();
+    a1.three = 4;
+    expect(a1).toEqual(a2);
+    expect(a2).toEqual(a1);
+
+    let a3 = new A();
+    let a4 = new A();
+    a3.three = 4;
+    // use indexed properties for slow path
+    a3[1] = 2;
+    a4[1] = 2;
+    expect(a3).toEqual(a4);
+    expect(a4).toEqual(a3);
+
+    let b1 = new B();
+    let a5 = new A();
+    expect(b1).toEqual(a5);
+    expect(a5).toEqual(b1);
+
+    b1.three = 4;
+    expect(b1).toEqual(a5);
+    expect(a5).toEqual(b1);
+
+    b1[1] = 2;
+    expect(b1).not.toEqual(a5);
+    expect(a5).not.toEqual(b1);
+
+    a5[1] = 2;
+    expect(b1).toEqual(a5);
+    expect(a5).toEqual(b1);
+  });
+
   test("properties with different circularity are not equal", () => {
     const a = {};
     a.x = { y: a };