fix: add exception check in JSC__JSValue__getPrototype

The getPrototype function was missing a proper exception check
using DECLARE_THROW_SCOPE and RETURN_IF_EXCEPTION. This fixes
exception validation when BUN_JSC_validateExceptionChecks is enabled.

Also fixed the exception check pattern in forEachPropertyImpl to check
for exceptions immediately after getPrototype returns, rather than
only in the else branch (when getPrototype returns null/falsy).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/bun.js/ConsoleObject.zig

@@ -2037,7 +2037,7 @@ pub const Formatter = struct {
         try value.getClassName(globalThis, &name_str);
         if (!name_str.eqlComptime("Object")) {
             return name_str;
-        } else if (value.getPrototype(globalThis).eqlValue(JSValue.null)) {
+        } else if ((try value.getPrototype(globalThis)) == .null) {
             return ZigString.static("[Object: null prototype]").*;
         }
         return null;
@@ -2318,7 +2318,7 @@ pub const Formatter = struct {
                 try value.getClassName(this.globalThis, &printable);
                 this.addForNewLine(printable.len);
 
-                const proto = value.getPrototype(this.globalThis);
+                const proto = try value.getPrototype(this.globalThis);
                 var printable_proto = ZigString.init(&name_buf);
                 try proto.getClassName(this.globalThis, &printable_proto);
                 this.addForNewLine(printable_proto.len);
@@ -2341,7 +2341,7 @@ pub const Formatter = struct {
                 var printable = try value.getName(this.globalThis);
                 defer printable.deref();
 
-                const proto = value.getPrototype(this.globalThis);
+                const proto = try value.getPrototype(this.globalThis);
                 const func_name = try proto.getName(this.globalThis); // "Function" | "AsyncFunction" | "GeneratorFunction" | "AsyncGeneratorFunction"
                 defer func_name.deref();
 

src/bun.js/bindings/JSValue.zig

@@ -1275,9 +1275,8 @@ pub const JSValue = enum(i64) {
     }
     extern fn JSC__JSValue__unwrapBoxedPrimitive(*JSGlobalObject, JSValue) JSValue;
 
-    extern fn JSC__JSValue__getPrototype(this: JSValue, globalObject: *JSGlobalObject) JSValue;
-    pub fn getPrototype(this: JSValue, globalObject: *JSGlobalObject) JSValue {
-        return JSC__JSValue__getPrototype(this, globalObject);
+    pub fn getPrototype(this: JSValue, globalObject: *JSGlobalObject) JSError!JSValue {
+        return bun.cpp.JSC__JSValue__getPrototype(this, globalObject);
     }
 
     extern fn JSC__JSValue__eqlValue(this: JSValue, other: JSValue) bool;

src/bun.js/bindings/bindings.cpp

@@ -3691,10 +3691,14 @@ bool JSC__JSValue__eqlValue(JSC::EncodedJSValue JSValue0, JSC::EncodedJSValue JS
 {
     return JSC::JSValue::decode(JSValue0) == JSC::JSValue::decode(JSValue1);
 };
-JSC::EncodedJSValue JSC__JSValue__getPrototype(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1)
+[[ZIG_EXPORT(zero_is_throw)]] JSC::EncodedJSValue JSC__JSValue__getPrototype(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* globalObject)
 {
+    auto& vm = JSC::getVM(globalObject);
+    auto scope = DECLARE_THROW_SCOPE(vm);
     auto value = JSC::JSValue::decode(JSValue0);
-    return JSC::JSValue::encode(value.getPrototype(arg1));
+    JSValue result = value.getPrototype(globalObject);
+    RETURN_IF_EXCEPTION(scope, {});
+    return JSC::JSValue::encode(result);
 }
 bool JSC__JSValue__isException(JSC::EncodedJSValue JSValue0, JSC::VM* arg1)
 {
@@ -4964,7 +4968,9 @@ static void JSC__JSValue__forEachPropertyImpl(JSC::EncodedJSValue JSValue0, JSC:
         if (structure->outOfLineSize() == 0 && structure->inlineSize() == 0) {
             fast = false;
 
-            if (JSValue proto = object->getPrototype(globalObject)) {
+            JSValue proto = object->getPrototype(globalObject);
+            RETURN_IF_EXCEPTION(scope, void());
+            if (proto) {
                 if ((structure = proto.structureOrNull())) {
                     prototypeObject = proto;
                     fast = canPerformFastPropertyEnumerationForIterationBun(structure);
@@ -5041,7 +5047,9 @@ restart:
         if (anyHits) {
             if (prototypeCount++ < 5) {
 
-                if (JSValue proto = prototypeObject.getPrototype(globalObject)) {
+                JSValue proto = prototypeObject.getPrototype(globalObject);
+                RETURN_IF_EXCEPTION(scope, void());
+                if (proto) {
                     if (!(proto == globalObject->objectPrototype() || proto == globalObject->functionPrototype() || (proto.inherits<JSGlobalProxy>() && jsCast<JSGlobalProxy*>(proto)->target() != globalObject))) {
                         if ((structure = proto.structureOrNull())) {
                             prototypeObject = proto;
@@ -5050,8 +5058,6 @@ restart:
                         }
                     }
                 }
-                // Ignore exceptions from Proxy "getPrototype" trap.
-                CLEAR_IF_EXCEPTION(scope);
             }
             return;
         }
@@ -5164,7 +5170,11 @@ restart:
                 break;
             if (iterating == globalObject)
                 break;
-            iterating = iterating->getPrototype(globalObject).getObject();
+
+            JSValue proto = iterating->getPrototype(globalObject);
+            RETURN_IF_EXCEPTION(scope, void());
+
+            iterating = proto.getObject();
         }
     }
 

src/bun.js/bindings/headers.h

@@ -229,7 +229,6 @@ CPP_DECL JSC::EncodedJSValue JSC__JSValue__getErrorsProperty(JSC::EncodedJSValue
 CPP_DECL JSC::EncodedJSValue JSC__JSValue__getIfPropertyExistsFromPath(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1, JSC::EncodedJSValue JSValue2);
 CPP_DECL double JSC__JSValue__getLengthIfPropertyExistsInternal(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1);
 CPP_DECL void JSC__JSValue__getNameProperty(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1, ZigString* arg2);
-CPP_DECL JSC::EncodedJSValue JSC__JSValue__getPrototype(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1);
 CPP_DECL void JSC__JSValue__getSymbolDescription(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1, ZigString* arg2);
 CPP_DECL double JSC__JSValue__getUnixTimestamp(JSC::EncodedJSValue JSValue0);
 CPP_DECL bool JSC__JSValue__hasOwnProperty(JSC::EncodedJSValue JSValue0, JSC::JSGlobalObject* arg1, ZigString arg2);

src/bun.js/bindings/napi.cpp

@@ -1831,7 +1831,9 @@ extern "C" napi_status napi_get_all_property_names(
                 // Climb up the prototype chain to find inherited properties
                 JSObject* current_object = object;
                 while (!current_object->getOwnPropertyDescriptor(globalObject, key.toPropertyKey(globalObject), desc)) {
-                    JSObject* proto = current_object->getPrototype(globalObject).getObject();
+                    JSValue protoValue = current_object->getPrototype(globalObject);
+                    NAPI_RETURN_IF_EXCEPTION(env);
+                    JSObject* proto = protoValue.getObject();
                     if (!proto) {
                         break;
                     }

src/bun.js/modules/NodeUtilTypesModule.cpp

@@ -140,6 +140,7 @@ JSC_DEFINE_HOST_FUNCTION(jsFunctionIsError,
         }
 
         JSValue proto = object->getPrototype(globalObject);
+        RETURN_IF_EXCEPTION(scope, {});
         if (proto.isCell() && (proto.inherits<JSC::ErrorInstance>() || proto.asCell()->type() == ErrorInstanceType || proto.inherits<JSC::ErrorPrototype>()))
             return JSValue::encode(jsBoolean(true));
     }

src/bun.js/test/ScopeFunctions.zig

@@ -453,7 +453,7 @@ pub fn createUnbound(globalThis: *JSGlobalObject, mode: Mode, each: jsc.JSValue,
 pub fn bind(value: JSValue, globalThis: *JSGlobalObject, name: bun.String) bun.JSError!JSValue {
     const callFn = jsc.JSFunction.create(globalThis, name, callAsFunction, 1, .{});
     const bound = try callFn.bind(globalThis, value, &name, 1, &.{});
-    try bound.setPrototypeDirect(value.getPrototype(globalThis), globalThis);
+    try bound.setPrototypeDirect(try value.getPrototype(globalThis), globalThis);
     return bound;
 }
 

src/bun.js/test/pretty_format.zig

@@ -725,7 +725,7 @@ pub const JestPrettyFormat = struct {
                         if (name_str.len > 0 and !name_str.eqlComptime("Object")) {
                             writer.print("{f} ", .{name_str});
                         } else {
-                            try value.getPrototype(globalThis).getNameProperty(globalThis, &name_str);
+                            try (try value.getPrototype(globalThis)).getNameProperty(globalThis, &name_str);
                             if (name_str.len > 0 and !name_str.eqlComptime("Object")) {
                                 writer.print("{f} ", .{name_str});
                             }

test/js/bun/util/inspect.test.js

@@ -82,6 +82,30 @@ it("getter/setters", () => {
   expect(Bun.inspect(obj)).toBe("{\n" + "  foo: [Getter/Setter]," + "\n" + "}");
 });
 
+it("stack overflow exception checks", () => {
+  function probe(value) {
+    let originalPrototype, newPrototype;
+    let handler = {
+      set(target, key, value, receiver) {
+        return Reflect.set(target, key, value, receiver);
+      },
+    };
+    originalPrototype = Object.getPrototypeOf(value);
+    newPrototype = new Proxy(originalPrototype, handler);
+    Object.setPrototypeOf(value, newPrototype);
+  }
+  class Foo {
+    get bar() {
+      Bun.inspect(this);
+    }
+  }
+  const foo = new Foo();
+  probe(foo);
+  expect(() => {
+    foo.bar(Foo, foo);
+  }).toThrow("Maximum call stack size exceeded");
+});
+
 it("Timeout", () => {
   const id = setTimeout(() => {}, 0);
   expect(Bun.inspect(id)).toBe(`Timeout (#${+id})`);