From 46b5de472e9174cb1e30bb44ad7166672a9e9530 Mon Sep 17 00:00:00 2001
From: David Kaya <david@kaya.sk>
Date: Wed, 25 Mar 2026 22:28:36 +0100
Subject: [PATCH] tests: some additional tests

---
 .../appServiceSidecarCapabilities.test.ts     | 118 +++++++++++++++
 tests/main/sidecarProcess.test.ts             | 138 ++++++++++++++++++
 2 files changed, 256 insertions(+)
 create mode 100644 tests/main/appServiceSidecarCapabilities.test.ts
 create mode 100644 tests/main/sidecarProcess.test.ts

diff --git a/tests/main/appServiceSidecarCapabilities.test.ts b/tests/main/appServiceSidecarCapabilities.test.ts
new file mode 100644
index 0000000..c50014e
--- /dev/null
+++ b/tests/main/appServiceSidecarCapabilities.test.ts
@@ -0,0 +1,118 @@
+import { describe, expect, mock, test } from 'bun:test';
+
+import type { SidecarCapabilities } from '@shared/contracts/sidecar';
+
+mock.module('electron', () => ({
+  app: {
+    isPackaged: false,
+    getAppPath: () => 'C:\\workspace\\personal\\repositories\\eryx',
+    getPath: () => 'C:\\workspace\\personal\\repositories\\eryx\\tests\\fixtures',
+  },
+  dialog: {
+    showOpenDialog: async () => ({ canceled: true, filePaths: [] }),
+  },
+  shell: {
+    openPath: async () => '',
+  },
+}));
+
+mock.module('keytar', () => ({
+  default: {
+    getPassword: async () => null,
+    setPassword: async () => undefined,
+    deletePassword: async () => false,
+  },
+}));
+
+const { EryxAppService } = await import('@main/EryxAppService');
+
+const SIDECAR_STOPPED_BEFORE_COMPLETION_MESSAGE =
+  'The .NET sidecar was stopped before the command completed.';
+
+const CAPABILITIES_FIXTURE: SidecarCapabilities = {
+  runtime: 'dotnet-maf',
+  modes: {
+    single: { available: true },
+    sequential: { available: true },
+    concurrent: { available: true },
+    handoff: { available: true },
+    magentic: { available: false, reason: 'Not yet supported.' },
+    'group-chat': { available: true },
+  },
+  models: [],
+  runtimeTools: [],
+  connection: {
+    status: 'ready',
+    summary: 'Connected',
+    checkedAt: '2026-03-25T00:00:00.000Z',
+  },
+};
+
+function setSidecar(
+  service: InstanceType<typeof EryxAppService>,
+  describeCapabilities: () => Promise<SidecarCapabilities>,
+): void {
+  (
+    service as unknown as {
+      sidecar: {
+        describeCapabilities: () => Promise<SidecarCapabilities>;
+        dispose: () => Promise<void>;
+      };
+    }
+  ).sidecar = {
+    describeCapabilities,
+    dispose: async () => undefined,
+  };
+}
+
+function createDeferred<T>() {
+  let resolve!: (value: T) => void;
+  const promise = new Promise<T>((resolvePromise) => {
+    resolve = resolvePromise;
+  });
+
+  return { promise, resolve };
+}
+
+describe('EryxAppService sidecar capabilities', () => {
+  test('retries describe-capabilities after an intentional sidecar stop', async () => {
+    const service = new EryxAppService();
+    let attempts = 0;
+
+    setSidecar(service, async () => {
+      attempts += 1;
+      if (attempts === 1) {
+        throw new Error(SIDECAR_STOPPED_BEFORE_COMPLETION_MESSAGE);
+      }
+
+      return CAPABILITIES_FIXTURE;
+    });
+
+    await expect(service.describeSidecarCapabilities()).resolves.toEqual(CAPABILITIES_FIXTURE);
+    expect(attempts).toBe(2);
+  });
+
+  test('coalesces concurrent capability requests while the cache is empty', async () => {
+    const service = new EryxAppService();
+    const deferred = createDeferred<SidecarCapabilities>();
+    let calls = 0;
+
+    setSidecar(service, async () => {
+      calls += 1;
+      return deferred.promise;
+    });
+
+    const first = service.describeSidecarCapabilities();
+    const second = service.describeSidecarCapabilities();
+
+    expect(calls).toBe(1);
+
+    deferred.resolve(CAPABILITIES_FIXTURE);
+
+    await expect(first).resolves.toEqual(CAPABILITIES_FIXTURE);
+    await expect(second).resolves.toEqual(CAPABILITIES_FIXTURE);
+    await expect(service.describeSidecarCapabilities()).resolves.toEqual(CAPABILITIES_FIXTURE);
+
+    expect(calls).toBe(1);
+  });
+});
diff --git a/tests/main/sidecarProcess.test.ts b/tests/main/sidecarProcess.test.ts
new file mode 100644
index 0000000..01a8c8c
--- /dev/null
+++ b/tests/main/sidecarProcess.test.ts
@@ -0,0 +1,138 @@
+import { EventEmitter } from 'node:events';
+
+import { describe, expect, mock, test } from 'bun:test';
+
+import type { SidecarCapabilities } from '@shared/contracts/sidecar';
+
+class FakeReadableStream extends EventEmitter {
+  setEncoding(_encoding: BufferEncoding): void {}
+}
+
+class FakeWritableStream {
+  readonly writes: string[] = [];
+
+  write(chunk: string): boolean {
+    this.writes.push(chunk);
+    return true;
+  }
+}
+
+class FakeChildProcess extends EventEmitter {
+  readonly stdout = new FakeReadableStream();
+  readonly stderr = new FakeReadableStream();
+  readonly stdin = new FakeWritableStream();
+  exitCode: number | null = null;
+  killed = false;
+
+  kill(): boolean {
+    this.killed = true;
+    return true;
+  }
+
+  emitStdout(line: string): void {
+    this.stdout.emit('data', line);
+  }
+
+  completeExit(code = 0): void {
+    this.exitCode = code;
+    this.emit('exit', code, null);
+    this.emit('close', code, null);
+  }
+}
+
+const spawnedProcesses: FakeChildProcess[] = [];
+
+mock.module('electron', () => ({
+  app: {
+    isPackaged: false,
+    getAppPath: () => 'C:\\workspace\\personal\\repositories\\eryx',
+  },
+}));
+
+mock.module('node:child_process', () => ({
+  spawn: () => {
+    const child = new FakeChildProcess();
+    spawnedProcesses.push(child);
+    return child;
+  },
+}));
+
+const { SidecarClient } = await import('@main/sidecar/sidecarProcess');
+
+const CAPABILITIES_FIXTURE: SidecarCapabilities = {
+  runtime: 'dotnet-maf',
+  modes: {
+    single: { available: true },
+    sequential: { available: true },
+    concurrent: { available: true },
+    handoff: { available: true },
+    magentic: { available: true },
+    'group-chat': { available: true },
+  },
+  models: [],
+  runtimeTools: [],
+  connection: {
+    status: 'ready',
+    summary: 'Connected',
+    checkedAt: '2026-03-25T00:00:00.000Z',
+  },
+};
+
+function getRequestId(process: FakeChildProcess): string {
+  const rawRequest = process.stdin.writes.at(-1);
+  if (!rawRequest) {
+    throw new Error('Expected the fake sidecar to receive a request.');
+  }
+
+  return (JSON.parse(rawRequest.trim()) as { requestId: string }).requestId;
+}
+
+describe('SidecarClient', () => {
+  test('waits for the disposed sidecar to fully close before spawning a replacement process', async () => {
+    spawnedProcesses.length = 0;
+    const client = new SidecarClient();
+
+    const firstCapabilities = client.describeCapabilities();
+    await Promise.resolve();
+    expect(spawnedProcesses).toHaveLength(1);
+    spawnedProcesses[0]!.emitStdout(
+      `${JSON.stringify({
+        type: 'capabilities',
+        requestId: getRequestId(spawnedProcesses[0]!),
+        capabilities: CAPABILITIES_FIXTURE,
+      })}\n`,
+    );
+    await expect(firstCapabilities).resolves.toEqual(CAPABILITIES_FIXTURE);
+
+    let disposeCompleted = false;
+    const disposePromise = client.dispose().then(() => {
+      disposeCompleted = true;
+    });
+
+    const replacementCapabilities = client.describeCapabilities();
+
+    await Promise.resolve();
+
+    expect(disposeCompleted).toBe(false);
+    expect(spawnedProcesses).toHaveLength(1);
+
+    spawnedProcesses[0]!.completeExit();
+    await disposePromise;
+
+    expect(disposeCompleted).toBe(true);
+    expect(spawnedProcesses).toHaveLength(2);
+
+    spawnedProcesses[1]!.emitStdout(
+      `${JSON.stringify({
+        type: 'capabilities',
+        requestId: getRequestId(spawnedProcesses[1]!),
+        capabilities: CAPABILITIES_FIXTURE,
+      })}\n`,
+    );
+    await expect(replacementCapabilities).resolves.toEqual(CAPABILITIES_FIXTURE);
+
+    const finalDispose = client.dispose();
+    spawnedProcesses[1]!.completeExit();
+    await finalDispose;
+  });
+});