Fix unchecked exception in Bun.plugin when target toString throws

src/jsc/bindings/BunPlugin.cpp

@@ -304,11 +304,13 @@ static inline JSC::EncodedJSValue setupBunPlugin(JSC::JSGlobalObject* globalObje
     if (targetValue) {
         if (auto* targetJSString = targetValue.toStringOrNull(globalObject)) {
             String targetString = targetJSString->value(globalObject);
+            RETURN_IF_EXCEPTION(throwScope, {});
             if (!(targetString == "node"_s || targetString == "bun"_s || targetString == "browser"_s)) {
                 JSC::throwTypeError(globalObject, throwScope, "plugin target must be one of 'node', 'bun' or 'browser'"_s);
                 return {};
             }
         }
+        RETURN_IF_EXCEPTION(throwScope, {});
     }
 
     JSObject* builderObject = JSC::constructEmptyObject(globalObject, globalObject->objectPrototype(), 4);

test/js/bun/plugin/plugins.test.ts

@@ -366,6 +366,21 @@ describe("errors", () => {
     }).toThrow("plugin target must be one of 'node', 'bun' or 'browser'");
   });
 
+  it("propagates exception from 'target' toString", () => {
+    const opts = {
+      setup: () => {},
+      target: {
+        toString() {
+          throw new Error("boom");
+        },
+      },
+    };
+
+    expect(() => {
+      plugin(opts as any);
+    }).toThrow("boom");
+  });
+
   it("invalid loaders throw", () => {
     const invalidLoaders = ["blah", "blah2", "blah3", "blah4"];
     const inputs = ["body { background: red; }", "<h1>hi</h1>", '{"hi": "there"}', "hi"];