fix: Crash in emit attempt when stream closed

src/Recording.ts

@@ -12,6 +12,7 @@ import { getDefaultMetadata } from "./metadata";
 import type { FunctionInfo } from "./registry";
 import compactObject from "./util/compactObject";
 import { shouldRecord } from "./recorderControl";
+import { warn } from "./message";
 
 export default class Recording {
   constructor(type: AppMap.RecorderType, recorder: string, ...names: string[]) {
@@ -180,7 +181,11 @@ export default class Recording {
     // (http, sqlite, pg, mysql, ...) will save some CPU cycles but
     // will complicate their code.
     if (!shouldRecord()) return;
-    assert(this.stream);
+
+    if (this.stream == undefined) {
+      warn("Event emitted while stream is closed");
+      return;
+    }
     this.stream.emit(event);
   }
 

src/__tests__/Recording.test.ts

@@ -23,4 +23,14 @@ describe(Recording.prototype.fixup, () => {
   });
 });
 
+describe("Recording", () => {
+  it("Does not throw when emit is called with stream closed", () => {
+    const recording = new Recording("tests", "test", "test");
+    const funInfo = createTestFn("testFun");
+    const call = recording.functionCall(funInfo, undefined, []);
+    recording.finish();
+    recording.functionReturn(call.id, "result", undefined);
+  });
+});
+
 jest.mock("../AppMapStream");