Fix Bun.serve error handler error param (#1359)

7 files changed, 37 insertions, 4 deletions

diff --git a/src/bun.js/api/server.zig b/src/bun.js/api/server.zig
index dea478d7a..9d66634d5 100644
--- a/src/bun.js/api/server.zig
+++ b/src/bun.js/api/server.zig
@@ -1460,6 +1460,15 @@ fn NewRequestContext(comptime ssl_enabled: bool, comptime debug_mode: bool, comp
             }
 
             if (response_value.isError() or response_value.isAggregateError(this.globalThis) or response_value.isException(this.globalThis.vm())) {
+                // cast exception to error instance
+                if (response_value.isException(this.globalThis.vm())) {
+                    const err = response_value.toError(this.globalThis);
+                    if (!err.isUndefinedOrNull()) {
+                        ctx.runErrorHandler(err);
+                        return;
+                    }
+                }
+
                 ctx.runErrorHandler(response_value);
 
                 return;
diff --git a/src/bun.js/bindings/bindings.cpp b/src/bun.js/bindings/bindings.cpp
index 0cba2185d..d0de85849 100644
--- a/src/bun.js/bindings/bindings.cpp
+++ b/src/bun.js/bindings/bindings.cpp
@@ -2556,6 +2556,20 @@ void JSC__JSValue__getNameProperty(JSC__JSValue JSValue0, JSC__JSGlobalObject* a
     arg2->len = 0;
 }
 
+JSC__JSValue JSC__JSValue__toError(JSC__JSValue JSValue0, JSC__JSGlobalObject* arg1)
+{
+    JSC::JSValue value = JSC::JSValue::decode(JSValue0);
+    if (JSC::Exception* jscException = JSC::jsDynamicCast<JSC::Exception*>(value)) {
+        if (JSC::ErrorInstance* error = JSC::jsDynamicCast<JSC::ErrorInstance*>(jscException->value())) {
+            return JSC::JSValue::encode(JSC::JSValue(error));
+        }
+    }
+    if (JSC::ErrorInstance* error = JSC::jsDynamicCast<JSC::ErrorInstance*>(value)) {
+        return JSC::JSValue::encode(JSC::JSValue(error));
+    }
+    return JSC::JSValue::encode(JSC::jsUndefined());
+}
+
 void JSC__JSValue__toZigException(JSC__JSValue JSValue0, JSC__JSGlobalObject* arg1,
     ZigException* exception)
 {
diff --git a/src/bun.js/bindings/bindings.zig b/src/bun.js/bindings/bindings.zig
index 021cd2d84..f927e47c7 100644
--- a/src/bun.js/bindings/bindings.zig
+++ b/src/bun.js/bindings/bindings.zig
@@ -3136,6 +3136,10 @@ pub const JSValue = enum(JSValueReprInt) {
         return cppFn("isTerminationException", .{ this, vm });
     }
 
+    pub fn toError(this: JSValue, global: *JSGlobalObject) JSValue {
+        return cppFn("toError", .{ this, global });
+    }
+
     pub fn toZigException(this: JSValue, global: *JSGlobalObject, exception: *ZigException) void {
         return cppFn("toZigException", .{ this, global, exception });
     }
@@ -3493,7 +3497,7 @@ pub const JSValue = enum(JSValueReprInt) {
         return this.asNullableVoid().?;
     }
 
-    pub const Extern = [_][]const u8{ "fastGet_", "getStaticProperty", "createUninitializedUint8Array", "fromInt64NoTruncate", "fromUInt64NoTruncate", "toUInt64NoTruncate", "asPromise", "toInt64", "_then", "put", "makeWithNameAndPrototype", "parseJSON", "symbolKeyFor", "symbolFor", "getSymbolDescription", "createInternalPromise", "asInternalPromise", "asArrayBuffer_", "fromEntries", "createTypeError", "createRangeError", "createObject2", "getIfPropertyExistsImpl", "jsType", "jsonStringify", "kind_", "isTerminationException", "isSameValue", "getLengthOfArray", "toZigString", "createStringArray", "createEmptyObject", "putRecord", "asPromise", "isClass", "getNameProperty", "getClassName", "getErrorsProperty", "toInt32", "toBoolean", "isInt32", "isIterable", "forEach", "isAggregateError", "toZigException", "isException", "toWTFString", "hasProperty", "getPropertyNames", "getDirect", "putDirect", "getIfExists", "asString", "asObject", "asNumber", "isError", "jsNull", "jsUndefined", "jsTDZValue", "jsBoolean", "jsDoubleNumber", "jsNumberFromDouble", "jsNumberFromChar", "jsNumberFromU16", "jsNumberFromInt64", "isBoolean", "isAnyInt", "isUInt32AsAnyInt", "isInt32AsAnyInt", "isNumber", "isString", "isBigInt", "isHeapBigInt", "isBigInt32", "isSymbol", "isPrimitive", "isGetterSetter", "isCustomGetterSetter", "isObject", "isCell", "asCell", "toString", "toStringOrNull", "toPropertyKey", "toPropertyKeyValue", "toObject", "toString", "getPrototype", "getPropertyByPropertyName", "eqlValue", "eqlCell", "isCallable" };
+    pub const Extern = [_][]const u8{ "fastGet_", "getStaticProperty", "createUninitializedUint8Array", "fromInt64NoTruncate", "fromUInt64NoTruncate", "toUInt64NoTruncate", "asPromise", "toInt64", "_then", "put", "makeWithNameAndPrototype", "parseJSON", "symbolKeyFor", "symbolFor", "getSymbolDescription", "createInternalPromise", "asInternalPromise", "asArrayBuffer_", "fromEntries", "createTypeError", "createRangeError", "createObject2", "getIfPropertyExistsImpl", "jsType", "jsonStringify", "kind_", "isTerminationException", "isSameValue", "getLengthOfArray", "toZigString", "createStringArray", "createEmptyObject", "putRecord", "asPromise", "isClass", "getNameProperty", "getClassName", "getErrorsProperty", "toInt32", "toBoolean", "isInt32", "isIterable", "forEach", "isAggregateError", "toError", "toZigException", "isException", "toWTFString", "hasProperty", "getPropertyNames", "getDirect", "putDirect", "getIfExists", "asString", "asObject", "asNumber", "isError", "jsNull", "jsUndefined", "jsTDZValue", "jsBoolean", "jsDoubleNumber", "jsNumberFromDouble", "jsNumberFromChar", "jsNumberFromU16", "jsNumberFromInt64", "isBoolean", "isAnyInt", "isUInt32AsAnyInt", "isInt32AsAnyInt", "isNumber", "isString", "isBigInt", "isHeapBigInt", "isBigInt32", "isSymbol", "isPrimitive", "isGetterSetter", "isCustomGetterSetter", "isObject", "isCell", "asCell", "toString", "toStringOrNull", "toPropertyKey", "toPropertyKeyValue", "toObject", "toString", "getPrototype", "getPropertyByPropertyName", "eqlValue", "eqlCell", "isCallable" };
 };
 
 extern "c" fn Microtask__run(*Microtask, *JSGlobalObject) void;
diff --git a/src/bun.js/bindings/headers-cpp.h b/src/bun.js/bindings/headers-cpp.h
index b0e3128dd..539e71afc 100644
--- a/src/bun.js/bindings/headers-cpp.h
+++ b/src/bun.js/bindings/headers-cpp.h
@@ -1,4 +1,4 @@
-//-- AUTOGENERATED FILE -- 1665449441
+//-- AUTOGENERATED FILE -- 1666254195
 // clang-format off
 #pragma once
 
diff --git a/src/bun.js/bindings/headers.h b/src/bun.js/bindings/headers.h
index 6e24d2e08..de4eb42d4 100644
--- a/src/bun.js/bindings/headers.h
+++ b/src/bun.js/bindings/headers.h
@@ -1,5 +1,5 @@
 // clang-format off
-//-- AUTOGENERATED FILE -- 1665449441
+//-- AUTOGENERATED FILE -- 1666254195
 #pragma once
 
 #include <stddef.h>
@@ -541,6 +541,7 @@ CPP_DECL void JSC__JSValue__putRecord(JSC__JSValue JSValue0, JSC__JSGlobalObject
 CPP_DECL JSC__JSValue JSC__JSValue__symbolFor(JSC__JSGlobalObject* arg0, ZigString* arg1);
 CPP_DECL bool JSC__JSValue__symbolKeyFor(JSC__JSValue JSValue0, JSC__JSGlobalObject* arg1, ZigString* arg2);
 CPP_DECL bool JSC__JSValue__toBoolean(JSC__JSValue JSValue0);
+CPP_DECL JSC__JSValue JSC__JSValue__toError(JSC__JSValue JSValue0, JSC__JSGlobalObject* arg1);
 CPP_DECL int32_t JSC__JSValue__toInt32(JSC__JSValue JSValue0);
 CPP_DECL int64_t JSC__JSValue__toInt64(JSC__JSValue JSValue0);
 CPP_DECL JSC__JSObject* JSC__JSValue__toObject(JSC__JSValue JSValue0, JSC__JSGlobalObject* arg1);
diff --git a/src/bun.js/bindings/headers.zig b/src/bun.js/bindings/headers.zig
index 2f23e8dac..242056ecb 100644
--- a/src/bun.js/bindings/headers.zig
+++ b/src/bun.js/bindings/headers.zig
@@ -334,6 +334,7 @@ pub extern fn JSC__JSValue__putRecord(JSValue0: JSC__JSValue, arg1: ?*JSC__JSGlo
 pub extern fn JSC__JSValue__symbolFor(arg0: ?*JSC__JSGlobalObject, arg1: [*c]ZigString) JSC__JSValue;
 pub extern fn JSC__JSValue__symbolKeyFor(JSValue0: JSC__JSValue, arg1: ?*JSC__JSGlobalObject, arg2: [*c]ZigString) bool;
 pub extern fn JSC__JSValue__toBoolean(JSValue0: JSC__JSValue) bool;
+pub extern fn JSC__JSValue__toError(JSValue0: JSC__JSValue, arg1: ?*JSC__JSGlobalObject) JSC__JSValue;
 pub extern fn JSC__JSValue__toInt32(JSValue0: JSC__JSValue) i32;
 pub extern fn JSC__JSValue__toInt64(JSValue0: JSC__JSValue) i64;
 pub extern fn JSC__JSValue__toObject(JSValue0: JSC__JSValue, arg1: ?*JSC__JSGlobalObject) [*c]JSC__JSObject;
diff --git a/test/bun.js/serve.test.ts b/test/bun.js/serve.test.ts
index 1ade9ed55..64634b841 100644
--- a/test/bun.js/serve.test.ts
+++ b/test/bun.js/serve.test.ts
@@ -206,18 +206,20 @@ describe("streaming", () => {
     var server;
     try {
       var pass = false;
+      var err = { name: '', message: '' };
       server = serve({
         port: port++,
         development: false,
         error(e) {
           pass = true;
+          err = e;
           return new Response("Fail", { status: 500 });
         },
         fetch(req) {
           return new Response(
             new ReadableStream({
               start(controller) {
-                throw new Error("error");
+                throw new TypeError("error");
               },
             })
           );
@@ -228,6 +230,8 @@ describe("streaming", () => {
       expect(response.status).toBe(500);
       expect(await response.text()).toBe("Fail");
       expect(pass).toBe(true);
+      expect(err.name).toBe("TypeError");
+      expect(err.message).toBe("error");
     } catch (e) {
       throw e;
     } finally {