fix(node-runtime-worker-thread): remove function properties before serializing errors COMPASS-5919

packages/node-runtime-worker-thread/src/index.spec.ts

@@ -144,6 +144,50 @@ describe('WorkerRuntime', function () {
           .to.have.property('stack')
           .matches(/SyntaxError: Syntax!/);
       });
+
+      it('COMPASS-5919 - correctly serializes babel parse errors', async function () {
+        /**
+         * babel syntax errors have a `clone()` method, which breaks structured cloning
+         */
+        runtime = new WorkerRuntime('mongodb://nodb/', dummyOptions, {
+          nodb: true,
+        });
+
+        const err: Error = await runtime.evaluate('1 +* 3').catch((e) => e);
+
+        expect(err).to.be.instanceof(Error);
+        expect(err).to.have.property('name', 'SyntaxError');
+      });
+
+      context(
+        'when `evaluate` returns an error that has a function property',
+        function () {
+          it('removes the function property from the error', async function () {
+            runtime = new WorkerRuntime('mongodb://nodb/', dummyOptions, {
+              nodb: true,
+            });
+
+            const script = `
+          class CustomError extends Error {
+            constructor() {
+              super('custom error');
+            }
+            foo() {
+              return 'hello, world';
+            }
+          }
+          throw new CustomError();
+          `;
+
+            const err: Error = await runtime.evaluate(script).catch((e) => e);
+
+            expect(err).to.be.instanceof(Error);
+            expect(err).to.have.property('name', 'Error');
+            expect(err).not.to.have.property('foo');
+            expect(err).to.have.property('message', 'custom error');
+          });
+        }
+      );
     });
   });
 

packages/node-runtime-worker-thread/src/serializer.ts

@@ -27,7 +27,10 @@ function getNames<T>(obj: T): (keyof T)[] {
  */
 export function serializeError(err: Error) {
   // Name is the only constructor property we care about
-  const keys = getNames(err).concat('name');
+  const keys = getNames(err)
+    .concat('name')
+    // structured cloning cannot handle functions
+    .filter((key) => typeof err[key] !== 'function');
   return keys.reduce((acc, key) => {
     (acc as any)[key] = err[key];
     return acc;