Convert test suite from Jest to Vitest (#3)

* Initial plan

* Initial exploration - understanding current test setup

Co-authored-by: pelikhan <[email protected]>

* Convert tests from Jest to Vitest

Co-authored-by: pelikhan <[email protected]>

* Update documentation to reflect inline mock usage

Co-authored-by: pelikhan <[email protected]>

* Fix formatting in vitest.config.ts

Co-authored-by: pelikhan <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: pelikhan <[email protected]>
Co-authored-by: Peli de Halleux <[email protected]>

Author: Copilot

.github/prompts/unit-test.prompt.md

@@ -13,10 +13,9 @@ Ensure you adhere to the following guidelines when creating unit tests:
 - Use descriptive test names that clearly convey their purpose
 - Ensure tests cover both the main path of success and edge cases
 - Use proper assertions to validate the expected outcomes
-- Use `jest` for writing and running tests
+- Use `vitest` for writing and running tests
 - Place unit tests in the `__tests__` directory
-- Use fixtures for any necessary test data, placed in the `__fixtures__`
-  directory
+- Use inline mocks with `vi.mock()` for mocking dependencies
 
 ## Example
 
@@ -26,13 +25,19 @@ Use the following as an example of how to structure your unit tests:
 /**
  * Unit tests for the action's main functionality, src/main.ts
  */
-import { jest } from '@jest/globals'
-import * as core from '../__fixtures__/core.js'
-import { wait } from '../__fixtures__/wait.js'
+import { vi, describe, beforeEach, afterEach, it, expect } from 'vitest'
 
-// Mocks should be declared before the module being tested is imported.
-jest.unstable_mockModule('@actions/core', () => core)
-jest.unstable_mockModule('../src/wait.js', () => ({ wait }))
+// Mock modules
+const mockCore = {
+  getInput: vi.fn(),
+  setOutput: vi.fn(),
+  setFailed: vi.fn()
+}
+
+const mockWait = vi.fn()
+
+vi.mock('@actions/core', () => mockCore)
+vi.mock('../src/wait.js', () => ({ wait: mockWait }))
 
 // The module being tested should be imported dynamically. This ensures that the
 // mocks are used in place of any actual dependencies.
@@ -41,21 +46,21 @@ const { run } = await import('../src/main.js')
 describe('main.ts', () => {
   beforeEach(() => {
     // Set the action's inputs as return values from core.getInput().
-    core.getInput.mockImplementation(() => '500')
+    mockCore.getInput.mockImplementation(() => '500')
 
     // Mock the wait function so that it does not actually wait.
-    wait.mockImplementation(() => Promise.resolve('done!'))
+    mockWait.mockImplementation(() => Promise.resolve('done!'))
   })
 
   afterEach(() => {
-    jest.resetAllMocks()
+    vi.resetAllMocks()
   })
 
   it('Sets the time output', async () => {
     await run()
 
     // Verify the time output was set.
-    expect(core.setOutput).toHaveBeenNthCalledWith(
+    expect(mockCore.setOutput).toHaveBeenNthCalledWith(
       1,
       'time',
       // Simple regex to match a time string in the format HH:MM:SS.
@@ -65,17 +70,17 @@ describe('main.ts', () => {
 
   it('Sets a failed status', async () => {
     // Clear the getInput mock and return an invalid value.
-    core.getInput.mockClear().mockReturnValueOnce('this is not a number')
+    mockCore.getInput.mockClear().mockReturnValueOnce('this is not a number')
 
     // Clear the wait mock and return a rejected promise.
-    wait
+    mockWait
       .mockClear()
       .mockRejectedValueOnce(new Error('milliseconds is not a number'))
 
     await run()
 
     // Verify that the action was marked as failed.
-    expect(core.setFailed).toHaveBeenNthCalledWith(
+    expect(mockCore.setFailed).toHaveBeenNthCalledWith(
       1,
       'milliseconds is not a number'
     )

AGENTS.md

@@ -13,7 +13,6 @@ it is generated from.
 
 | Path                 | Description                                              |
 | -------------------- | -------------------------------------------------------- |
-| `__fixtures__/`      | Unit Test Fixtures                                       |
 | `__tests__/`         | Unit Tests                                               |
 | `.devcontainer/`     | Development Container Configuration                      |
 | `.github/`           | GitHub Configuration                                     |
@@ -31,7 +30,7 @@ it is generated from.
 | `action.yml`         | GitHub Action Metadata                                   |
 | `CODEOWNERS`         | Code Owners File                                         |
 | `eslint.config.mjs`  | ESLint Configuration                                     |
-| `jest.config.js`     | Jest Configuration                                       |
+| `vitest.config.ts`   | Vitest Configuration                                     |
 | `LICENSE`            | License File                                             |
 | `package.json`       | NPM Package Configuration                                |
 | `README.md`          | Project Documentation                                    |
@@ -55,7 +54,7 @@ npm run test
 ```
 
 Unit tests should exist in the `__tests__` directory. They are powered by
-`jest`. Fixtures should be placed in the `__fixtures__` directory.
+`vitest`.
 
 ## Bundling
 

__fixtures__/core.ts

@@ -1,62 +1,97 @@
 /**
  * Unit tests for the action's main functionality, src/main.ts
- *
- * To mock dependencies in ESM, you can create fixtures that export mock
- * functions and objects. For example, the core module is mocked in this test,
- * so that the actual '@actions/core' module is not imported.
  */
-import { jest } from '@jest/globals'
-import * as core from '../__fixtures__/core.js'
-import { wait } from '../__fixtures__/wait.js'
+import { vi, describe, beforeEach, afterEach, it, expect } from 'vitest'
 
-// Mocks should be declared before the module being tested is imported.
-jest.unstable_mockModule('@actions/core', () => core)
-jest.unstable_mockModule('../src/wait.js', () => ({ wait }))
+// Mock modules
+const mockCore = {
+  getInput: vi.fn(),
+  setOutput: vi.fn(),
+  setFailed: vi.fn(),
+  debug: vi.fn(),
+  error: vi.fn(),
+  info: vi.fn(),
+  warning: vi.fn()
+}
 
-// The module being tested should be imported dynamically. This ensures that the
-// mocks are used in place of any actual dependencies.
+const mockStartProxy = vi.fn()
+
+vi.mock('@actions/core', () => mockCore)
+vi.mock('../src/server.js', () => ({
+  startProxy: mockStartProxy
+}))
+
+// Import the module being tested
 const { run } = await import('../src/main.js')
 
 describe('main.ts', () => {
   beforeEach(() => {
-    // Set the action's inputs as return values from core.getInput().
-    core.getInput.mockImplementation(() => '500')
-
-    // Mock the wait function so that it does not actually wait.
-    wait.mockImplementation(() => Promise.resolve('done!'))
+    vi.clearAllMocks()
   })
 
   afterEach(() => {
-    jest.resetAllMocks()
+    vi.resetAllMocks()
   })
 
-  it('Sets the time output', async () => {
+  it('Sets the outputs on success', async () => {
+    // Setup mocks
+    mockCore.getInput.mockReturnValue('http://example.com')
+    mockStartProxy.mockResolvedValue({
+      url: 'http://localhost:3000',
+      port: 3000,
+      apiKey: 'test-api-key',
+      containerId: 'test-container-id'
+    })
+
     await run()
 
-    // Verify the time output was set.
-    expect(core.setOutput).toHaveBeenNthCalledWith(
-      1,
-      'time',
-      // Simple regex to match a time string in the format HH:MM:SS.
-      expect.stringMatching(/^\d{2}:\d{2}:\d{2}/)
+    // Verify outputs were set
+    expect(mockCore.setOutput).toHaveBeenCalledWith(
+      'url',
+      'http://localhost:3000'
+    )
+    expect(mockCore.setOutput).toHaveBeenCalledWith('port', 3000)
+    expect(mockCore.setOutput).toHaveBeenCalledWith('api-key', 'test-api-key')
+    expect(mockCore.setOutput).toHaveBeenCalledWith(
+      'container-id',
+      'test-container-id'
     )
+    expect(mockCore.setFailed).not.toHaveBeenCalled()
   })
 
-  it('Sets a failed status', async () => {
-    // Clear the getInput mock and return an invalid value.
-    core.getInput.mockClear().mockReturnValueOnce('this is not a number')
+  it('Sets a failed status on error', async () => {
+    // Setup mocks
+    mockCore.getInput.mockReturnValue('http://example.com')
+    mockStartProxy.mockRejectedValue(new Error('Connection failed'))
 
-    // Clear the wait mock and return a rejected promise.
-    wait
-      .mockClear()
-      .mockRejectedValueOnce(new Error('milliseconds is not a number'))
+    await run()
+
+    // Verify that the action was marked as failed
+    expect(mockCore.setFailed).toHaveBeenCalledWith('Connection failed')
+  })
+
+  it('Does not set container-id output when not present', async () => {
+    // Setup mocks
+    mockCore.getInput.mockReturnValue('http://example.com')
+    mockStartProxy.mockResolvedValue({
+      url: 'http://localhost:3000',
+      port: 3000,
+      apiKey: 'test-api-key'
+      // No containerId
+    })
 
     await run()
 
-    // Verify that the action was marked as failed.
-    expect(core.setFailed).toHaveBeenNthCalledWith(
-      1,
-      'milliseconds is not a number'
+    // Verify container-id was not set
+    expect(mockCore.setOutput).toHaveBeenCalledWith(
+      'url',
+      'http://localhost:3000'
+    )
+    expect(mockCore.setOutput).toHaveBeenCalledWith('port', 3000)
+    expect(mockCore.setOutput).toHaveBeenCalledWith('api-key', 'test-api-key')
+    expect(mockCore.setOutput).not.toHaveBeenCalledWith(
+      'container-id',
+      expect.anything()
     )
   })
 })

__fixtures__/wait.ts

@@ -6,7 +6,6 @@ import js from '@eslint/js'
 import typescriptEslint from '@typescript-eslint/eslint-plugin'
 import tsParser from '@typescript-eslint/parser'
 import _import from 'eslint-plugin-import'
-import jest from 'eslint-plugin-jest'
 import prettier from 'eslint-plugin-prettier'
 import globals from 'globals'
 
@@ -24,21 +23,18 @@ export default [
     'eslint:recommended',
     'plugin:@typescript-eslint/eslint-recommended',
     'plugin:@typescript-eslint/recommended',
-    'plugin:jest/recommended',
     'plugin:prettier/recommended'
   ),
   {
     plugins: {
       import: fixupPluginRules(_import),
-      jest,
       prettier,
       '@typescript-eslint': typescriptEslint
     },
 
     languageOptions: {
       globals: {
         ...globals.node,
-        ...globals.jest,
         Atomics: 'readonly',
         SharedArrayBuffer: 'readonly'
       },
@@ -53,7 +49,7 @@ export default [
             '__fixtures__/*.ts',
             '__tests__/*.ts',
             'eslint.config.mjs',
-            'jest.config.js',
+            'vitest.config.ts',
             'rollup.config.ts'
           ]
         },