From 864c5fd45309c96462003587b21ba9e5b0c2f7e8 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Fri, 15 May 2026 10:54:12 +0000
Subject: [PATCH] test: Add tests for `connectWorkerPort` in `rpc.ts`

Adds full test coverage for the previously untested `connectWorkerPort` function inside `src/core/rpc.ts`. Tests cover all major scenarios:
- Successful routing of invocations and responses
- Correct handling of Transfer objects via `postMessage`
- Fallback behavior to copying when transfer lists fail or throw
- Routing of logs to the provided `onLog` callback
---
 tests/unit/rpc.test.ts | 141 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 139 insertions(+), 2 deletions(-)

diff --git a/tests/unit/rpc.test.ts b/tests/unit/rpc.test.ts
index 279e8ef..8c7ff46 100644
--- a/tests/unit/rpc.test.ts
+++ b/tests/unit/rpc.test.ts
@@ -1,6 +1,6 @@
-import { describe, it } from 'node:test';
+import { describe, it, afterEach } from 'node:test';
 import assert from 'node:assert';
-import { processProtocolMessage, buildMethodProxy, Transfer } from '../../src/core/rpc';
+import { processProtocolMessage, buildMethodProxy, connectWorkerPort, WorkerPort, Transfer } from '../../src/core/rpc';
 
 describe('RPC', () => {
   describe('processProtocolMessage', () => {
@@ -149,4 +149,141 @@ describe('RPC', () => {
       assert.strictEqual(transfer[0], buffer);
     });
   });
+
+  describe('connectWorkerPort', () => {
+    let originalWarn: any;
+
+    afterEach(() => {
+      if (originalWarn) {
+        console.warn = originalWarn;
+        originalWarn = undefined;
+      }
+    });
+
+    it('should route invocations and responses', async () => {
+      let messageHandler: ((data: any) => void) | undefined;
+      let postedMessage: any;
+
+      const port: WorkerPort = {
+        postMessage: (msg: any, transfer: any) => {
+          postedMessage = msg;
+        },
+        on: (event: string, handler: any) => {
+          if (event === 'message') messageHandler = handler;
+        }
+      };
+
+      const proxy = connectWorkerPort<{ add: (a: number, b: number) => Promise<number> }>(
+        port,
+        ['add']
+      );
+
+      assert.ok(messageHandler);
+
+      // Call proxy
+      const promise = proxy.add(2, 3);
+
+      // Check envelope
+      assert.strictEqual(postedMessage.kind, 'invoke');
+      assert.strictEqual(postedMessage.methodName, 'add');
+      assert.deepStrictEqual(postedMessage.parameters, [2, 3]);
+
+      // Emulate reply
+      messageHandler({
+        kind: 'result',
+        correlationId: postedMessage.correlationId,
+        payload: 5
+      });
+
+      const result = await promise;
+      assert.strictEqual(result, 5);
+    });
+
+    it('should pass transfer list to postMessage', async () => {
+      let postedTransfer: any;
+
+      const port: WorkerPort = {
+        postMessage: (msg: any, transfer: any) => {
+          postedTransfer = transfer;
+        },
+        on: () => {}
+      };
+
+      const proxy = connectWorkerPort<{ send: (data: any) => Promise<void> }>(
+        port,
+        ['send']
+      );
+
+      const buffer = new ArrayBuffer(8);
+      proxy.send(new Transfer({ buf: buffer }, [buffer])).catch(() => {});
+
+      assert.strictEqual(postedTransfer?.length, 1);
+      assert.strictEqual(postedTransfer?.[0], buffer);
+    });
+
+    it('should fallback to copy if transfer throws', async () => {
+      let callCount = 0;
+      let hadTransfer = false;
+      let fallbackMessage = null;
+
+      originalWarn = console.warn;
+      let warnCalled = false;
+      console.warn = () => { warnCalled = true; };
+
+      const port: WorkerPort = {
+        postMessage: (msg: any, transfer: any) => {
+          callCount++;
+          if (transfer && transfer.length > 0) {
+            hadTransfer = true;
+            throw new Error('Transfer not supported');
+          } else {
+            fallbackMessage = msg;
+          }
+        },
+        on: () => {}
+      };
+
+      const proxy = connectWorkerPort<{ send: (data: any) => Promise<void> }>(
+        port,
+        ['send']
+      );
+
+      const buffer = new ArrayBuffer(8);
+      proxy.send(new Transfer({ buf: buffer }, [buffer])).catch(() => {});
+
+      assert.strictEqual(callCount, 2);
+      assert.strictEqual(hadTransfer, true);
+      assert.ok(fallbackMessage);
+      assert.strictEqual(warnCalled, true);
+    });
+
+    it('should route log messages to onLog', () => {
+      let messageHandler: ((data: any) => void) | undefined;
+      let logLevel: string | null = null;
+      let logArgs: any = null;
+
+      const port: WorkerPort = {
+        postMessage: () => {},
+        on: (event: string, handler: any) => {
+          if (event === 'message') messageHandler = handler;
+        }
+      };
+
+      connectWorkerPort(port, [], (level, args) => {
+        logLevel = level;
+        logArgs = args;
+      });
+
+      assert.ok(messageHandler);
+
+      messageHandler({
+        kind: 'log',
+        level: 'info',
+        args: ['hello world']
+      });
+
+      assert.strictEqual(logLevel, 'info');
+      assert.deepStrictEqual(logArgs, ['hello world']);
+    });
+  });
 });