Add a Test

How to add a new test to Ollama Copilot. Covers both test harnesses.

Step 1 — Choose the Harness

If the code under test…	Use	Location
Uses `vscode` API, extension activation, storage URIs, workspace folders	Extension host (Mocha)	`tests/extension/suite/`
Is a backend service (database, HTTP client, session index, terminal)	Extension host (Mocha)	`tests/extension/suite/services/`
Is a pure utility (no `vscode` dependency)	Extension host (Mocha)	`tests/extension/suite/utils/`
Lives in `src/webview/scripts/core/*` (state, actions, computed, handlers)	Webview (Vitest)	`tests/webview/core/`
Is a Vue component	Webview (Vitest)	`tests/webview/components/`

Step 2 — Create the Test File

Extension host test

Create tests/extension/suite/<category>/<moduleName>.test.ts:

typescript

import * as assert from 'assert';
// Import from source — note the path prefix
import { myFunction } from '../../../../src/utils/myModule';

suite('myFunction', () => {
  test('returns expected result for valid input', () => {
    const result = myFunction('input');
    assert.strictEqual(result, 'expected');
  });

  test('handles edge case', () => {
    assert.throws(() => myFunction(''), /error message/);
  });
});

Import path reference:

Test in	Import prefix to reach `src/`
`suite/*.test.ts`	`../../../src/`
`suite/agent/*.test.ts`	`../../../../src/`
`suite/services/*.test.ts`	`../../../../src/`
`suite/utils/*.test.ts`	`../../../../src/`
Mock server	`../../mocks/ollamaMockServer`

Required conventions:

•Use tdd style: suite() + test() (not describe/it)
•Use Node's assert module (not expect)
•Use async test functions when awaiting
•If you need the mock Ollama server: import { startOllamaMockServer } from '../../mocks/ollamaMockServer';
•If you need VS Code APIs: import * as vscode from 'vscode';

Webview test (core logic)

Create tests/webview/core/<moduleName>.test.ts:

typescript

import { beforeEach, describe, expect, test, vi } from 'vitest';

beforeEach(() => {
  vi.useFakeTimers();
  vi.setSystemTime(new Date('2026-02-03T00:00:00Z'));
  vi.resetModules();
});

afterEach(() => {
  vi.useRealTimers();
});

describe('myModule', () => {
  test('does something', async () => {
    // Dynamic import for fresh module instance
    const state = await import('../../../src/webview/scripts/core/state');
    const myModule = await import('../../../src/webview/scripts/core/myModule');

    state.someValue.value = 'test';
    expect(myModule.computedThing.value).toBe('expected');
  });
});

Critical: Use vi.resetModules() + await import() to get fresh module instances. Static imports share state across tests.

Webview test (Vue component)

Create tests/webview/components/<ComponentName>.test.ts:

typescript

import { mount } from '@vue/test-utils';
import { describe, expect, test, vi } from 'vitest';
import MyComponent from '../../../src/webview/components/chat/components/MyComponent.vue';

// Mock dependencies if needed
vi.mock('../../../src/webview/scripts/core/actions', () => ({
  someAction: vi.fn()
}));

describe('MyComponent', () => {
  test('renders with default props', () => {
    const wrapper = mount(MyComponent, {
      props: { /* ... */ }
    });
    expect(wrapper.text()).toContain('expected text');
  });
});

Import path reference for webview tests:

Test in	Import prefix to reach `src/webview/`
`core/*.test.ts`	`../../../src/webview/`
`components/*.test.ts`	`../../../src/webview/`

Step 3 — Run and Verify

bash

# Extension host test
npm test

# Webview test
npm run test:webview

# All tests
npm run test:all

No test registration is needed — both harnesses auto-discover *.test.ts / *.test.js files via globs.

Step 4 — Update Coverage Catalog

After adding the test, update the "Existing test coverage" sections in .github/instructions/testing.instructions.md with:

•Suite name and test count
•Brief description of what it covers

Common Patterns

Testing postMessage calls (webview)

typescript

import { vscodePostMessage } from '../setup';

test('sends message on action', async () => {
  vscodePostMessage.mockClear();
  const actions = await import('../../../src/webview/scripts/core/actions/index');

  actions.doSomething();

  expect(vscodePostMessage).toHaveBeenCalledWith({
    type: 'expectedMessageType',
    // ...expected payload
  });
});

Testing with the Ollama mock server (extension)

typescript

import { startOllamaMockServer } from '../../mocks/ollamaMockServer';

suite('MyService', () => {
  test('handles API response', async () => {
    const server = await startOllamaMockServer({ type: 'chatEcho' });
    try {
      const client = new OllamaClient(server.baseUrl);
      const result = await client.listModels();
      assert.ok(result.length > 0);
    } finally {
      await server.close();
    }
  });
});

Testing database services (extension)

typescript

import * as vscode from 'vscode';
import { MyService } from '../../../../src/services/myService';

function getExtensionUri(): vscode.Uri {
  const ext = vscode.extensions.getExtension('ollama-copilot.ollama-copilot');
  assert.ok(ext);
  return ext.extensionUri;
}

// Create temp dirs for isolated DB testing
async function makeTempDir(prefix: string): Promise<string> {
  const base = path.join(os.tmpdir(), 'ollama-copilot-tests');
  await fs.mkdir(base, { recursive: true });
  return fs.mkdtemp(path.join(base, `${prefix}-`));
}