feat: migrate to ESM and update dependencies (#949)

* feat: migrate to ESM and update dependencies

- Migrated the project to ESM to support the latest `@actions/*` package versions.
- Updated dependencies to their latest versions, including `@actions/core`, `@actions/github`, and others.
- Replaced `.prettierrc.js` with `.prettierrc.json` for configuration.
- Updated ESLint configuration to use ESM and added new rules.
- Refactored test files to use `jest` with ESM imports.
- Removed deprecated files and updated import paths to use `.js` extensions.
- Added new files for improved configuration and removed unnecessary mocks.
- Updated README to reflect breaking changes in version 7.

* docs: update README to clarify ESM migration details and adjust TypeScript configuration

__tests__/branch.test.ts

@@ -1,14 +1,31 @@
-import {
-  getBranchName,
-  checkAnyBranch,
-  checkAllBranch,
-  toBranchMatchConfig,
-  BranchMatchConfig
-} from '../src/branch';
-import * as github from '@actions/github';
+import {jest, describe, beforeEach, it, expect} from '@jest/globals';
+import type {BranchMatchConfig} from '../src/branch.js';
 
-jest.mock('@actions/core');
-jest.mock('@actions/github');
+jest.unstable_mockModule('@actions/core', () => ({
+  debug: jest.fn(),
+  info: jest.fn(),
+  warning: jest.fn(),
+  error: jest.fn()
+}));
+
+const mockGithubContext = {
+  payload: {
+    pull_request: {
+      number: 123,
+      head: {ref: 'head-branch-name'},
+      base: {ref: 'base-branch-name'}
+    }
+  },
+  repo: {owner: 'monalisa', repo: 'helloworld'}
+} as any;
+
+jest.unstable_mockModule('@actions/github', () => ({
+  context: mockGithubContext,
+  getOctokit: jest.fn()
+}));
+
+const {getBranchName, checkAnyBranch, checkAllBranch, toBranchMatchConfig} =
+  await import('../src/branch.js');
 
 describe('getBranchName', () => {
   describe('when the pull requests base branch is requested', () => {
@@ -28,10 +45,10 @@ describe('getBranchName', () => {
 
 describe('checkAllBranch', () => {
   beforeEach(() => {
-    github.context.payload.pull_request!.head = {
+    mockGithubContext.payload.pull_request.head = {
       ref: 'test/feature/123'
     };
-    github.context.payload.pull_request!.base = {
+    mockGithubContext.payload.pull_request.base = {
       ref: 'main'
     };
   });
@@ -87,10 +104,10 @@ describe('checkAllBranch', () => {
 
 describe('checkAnyBranch', () => {
   beforeEach(() => {
-    github.context.payload.pull_request!.head = {
+    mockGithubContext.payload.pull_request.head = {
       ref: 'test/feature/123'
     };
-    github.context.payload.pull_request!.base = {
+    mockGithubContext.payload.pull_request.base = {
       ref: 'main'
     };
   });
@@ -159,7 +176,7 @@ describe('toBranchMatchConfig', () => {
 
     it('sets headBranch in the matchConfig', () => {
       const result = toBranchMatchConfig(config);
-      expect(result).toEqual<BranchMatchConfig>({
+      expect(result).toEqual({
         headBranch: ['testing']
       });
     });
@@ -169,7 +186,7 @@ describe('toBranchMatchConfig', () => {
 
       it('sets headBranch in the matchConfig', () => {
         const result = toBranchMatchConfig(stringConfig);
-        expect(result).toEqual<BranchMatchConfig>({
+        expect(result).toEqual({
           headBranch: ['testing']
         });
       });
@@ -180,7 +197,7 @@ describe('toBranchMatchConfig', () => {
     const config = {'base-branch': ['testing']};
     it('sets baseBranch in the matchConfig', () => {
       const result = toBranchMatchConfig(config);
-      expect(result).toEqual<BranchMatchConfig>({
+      expect(result).toEqual({
         baseBranch: ['testing']
       });
     });
@@ -190,7 +207,7 @@ describe('toBranchMatchConfig', () => {
 
       it('sets baseBranch in the matchConfig', () => {
         const result = toBranchMatchConfig(stringConfig);
-        expect(result).toEqual<BranchMatchConfig>({
+        expect(result).toEqual({
           baseBranch: ['testing']
         });
       });
@@ -201,7 +218,7 @@ describe('toBranchMatchConfig', () => {
     const config = {'base-branch': ['testing'], 'head-branch': ['testing']};
     it('sets headBranch and baseBranch in the matchConfig', () => {
       const result = toBranchMatchConfig(config);
-      expect(result).toEqual<BranchMatchConfig>({
+      expect(result).toEqual({
         baseBranch: ['testing'],
         headBranch: ['testing']
       });

__tests__/changedFiles.test.ts

@@ -1,5 +1,24 @@
-import {
-  ChangedFilesMatchConfig,
+import {jest, describe, it, expect} from '@jest/globals';
+import type {ChangedFilesMatchConfig} from '../src/changedFiles.js';
+
+jest.unstable_mockModule('@actions/core', () => ({
+  debug: jest.fn(),
+  info: jest.fn(),
+  warning: jest.fn(),
+  error: jest.fn()
+}));
+
+jest.unstable_mockModule('@actions/github', () => ({
+  context: {
+    payload: {
+      pull_request: {number: 123, head: {ref: 'head'}, base: {ref: 'base'}}
+    },
+    repo: {owner: 'monalisa', repo: 'helloworld'}
+  },
+  getOctokit: jest.fn()
+}));
+
+const {
   checkAllChangedFiles,
   checkAnyChangedFiles,
   toChangedFilesMatchConfig,
@@ -7,10 +26,7 @@ import {
   checkIfAllGlobsMatchAnyFile,
   checkIfAnyGlobMatchesAllFiles,
   checkIfAllGlobsMatchAllFiles
-} from '../src/changedFiles';
-
-jest.mock('@actions/core');
-jest.mock('@actions/github');
+} = await import('../src/changedFiles.js');
 
 describe('checkAllChangedFiles', () => {
   const changedFiles = ['foo.txt', 'bar.txt'];
@@ -92,7 +108,7 @@ describe('toChangedFilesMatchConfig', () => {
 
     it('returns an empty object', () => {
       const result = toChangedFilesMatchConfig(config);
-      expect(result).toEqual<ChangedFilesMatchConfig>({});
+      expect(result).toEqual({});
     });
   });
 
@@ -129,7 +145,7 @@ describe('toChangedFilesMatchConfig', () => {
 
         it('sets the value in the config object', () => {
           const result = toChangedFilesMatchConfig(config);
-          expect(result).toEqual<ChangedFilesMatchConfig>({
+          expect(result).toEqual({
             changedFiles: [{anyGlobToAnyFile: ['testing']}]
           });
         });
@@ -140,7 +156,7 @@ describe('toChangedFilesMatchConfig', () => {
 
         it(`sets the string as an array in the config object`, () => {
           const result = toChangedFilesMatchConfig(config);
-          expect(result).toEqual<ChangedFilesMatchConfig>({
+          expect(result).toEqual({
             changedFiles: [{anyGlobToAnyFile: ['testing']}]
           });
         });

__tests__/labeler.test.ts

@@ -1,26 +1,65 @@
+import {jest, describe, it, expect, beforeEach, beforeAll} from '@jest/globals';
 import * as yaml from 'js-yaml';
-import * as core from '@actions/core';
-import * as api from '../src/api';
-import {labeler} from '../src/labeler';
-import * as github from '@actions/github';
 import * as fs from 'fs';
-import {checkMatchConfigs} from '../src/labeler';
-import {
+import type {
   MatchConfig,
+  BaseMatchConfig
+} from '../src/api/get-label-configs.js';
+
+// Define API mock functions at module level
+const getPullRequestsMock = jest.fn<any>();
+const getLabelConfigsMock = jest.fn<any>();
+const setLabelsMock = jest.fn<any>();
+const getChangedFilesMock = jest.fn<any>();
+const getContentMock = jest.fn<any>();
+
+jest.unstable_mockModule('@actions/core', () => ({
+  getInput: jest.fn(),
+  getMultilineInput: jest.fn(),
+  getBooleanInput: jest.fn(),
+  setOutput: jest.fn(),
+  setFailed: jest.fn(),
+  error: jest.fn(),
+  warning: jest.fn(),
+  info: jest.fn(),
+  debug: jest.fn()
+}));
+
+jest.unstable_mockModule('@actions/github', () => ({
+  context: {
+    payload: {
+      pull_request: {
+        number: 123,
+        head: {ref: 'head-branch'},
+        base: {ref: 'base-branch'}
+      }
+    },
+    repo: {owner: 'monalisa', repo: 'helloworld'}
+  },
+  getOctokit: jest.fn()
+}));
+
+jest.unstable_mockModule('../src/api/index.js', () => ({
+  getPullRequests: getPullRequestsMock,
+  getLabelConfigs: getLabelConfigsMock,
+  setLabels: setLabelsMock,
+  getChangedFiles: getChangedFilesMock,
+  getContent: getContentMock
+}));
+
+const core = await import('@actions/core');
+const github = await import('@actions/github');
+const api = await import('../src/api/index.js');
+const {labeler, checkMatchConfigs} = await import('../src/labeler.js');
+const {
   toMatchConfig,
   getLabelConfigMapFromObject,
   getLabelConfigResultFromObject,
-  BaseMatchConfig,
   configUsesChangedFiles
-} from '../src/api/get-label-configs';
-
-jest.mock('@actions/core');
-jest.mock('../src/api');
+} = await import('../src/api/get-label-configs.js');
 
 beforeAll(() => {
-  jest.spyOn(core, 'getInput').mockImplementation((name, options) => {
-    return jest.requireActual('@actions/core').getInput(name, options);
-  });
+  (core.getInput as jest.Mock).mockImplementation(() => undefined);
 });
 
 const loadYaml = (filepath: string) => {
@@ -422,14 +461,14 @@ describe('labeler error handling', () => {
     jest.resetAllMocks();
 
     (github.getOctokit as jest.Mock).mockReturnValue(mockClient);
-    (api.getPullRequests as jest.Mock).mockReturnValue([
+    getPullRequestsMock.mockReturnValue([
       {
         ...mockPullRequest,
         data: {labels: [{name: 'old-label'}]}
       }
     ]);
 
-    (api.getLabelConfigs as jest.Mock).mockResolvedValue({
+    getLabelConfigsMock.mockResolvedValue({
       labelConfigs: new Map([['new-label', ['dummy-config']]]),
       changedFilesLimit: undefined
     });
@@ -439,7 +478,7 @@ describe('labeler error handling', () => {
   });
 
   it('throws a custom error for HttpError 403 with "unauthorized" message', async () => {
-    (api.setLabels as jest.Mock).mockRejectedValue({
+    setLabelsMock.mockRejectedValue({
       name: 'HttpError',
       status: 403,
       message: 'Request failed with status code 403: Unauthorized'
@@ -456,7 +495,7 @@ describe('labeler error handling', () => {
       status: 404,
       message: 'Not Found'
     };
-    (api.setLabels as jest.Mock).mockRejectedValue(unexpectedError);
+    setLabelsMock.mockRejectedValue(unexpectedError);
 
     // NOTE: In the current implementation, labeler rethrows the raw error object (not an Error instance).
     // `rejects.toThrow` only works with real Error objects, so here we must use `rejects.toEqual`.
@@ -469,7 +508,7 @@ describe('labeler error handling', () => {
       name: 'HttpError',
       message: 'Resource not accessible by integration'
     };
-    (api.setLabels as jest.Mock).mockRejectedValue(error);
+    setLabelsMock.mockRejectedValue(error);
 
     await labeler();
 

__tests__/main.test.ts

@@ -1,23 +1,75 @@
-import {run} from '../src/labeler';
-import * as github from '@actions/github';
-import * as core from '@actions/core';
+import {
+  jest,
+  describe,
+  it,
+  test,
+  expect,
+  afterAll,
+  beforeEach
+} from '@jest/globals';
 import path from 'path';
+import {fileURLToPath} from 'url';
 import fs from 'fs';
 
-jest.mock('@actions/core');
-jest.mock('@actions/github');
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+// Define mock functions before mocking modules
+const setLabelsMock = jest.fn<any>();
+const reposMock = jest.fn<any>();
+const paginateMock = jest.fn<any>();
+const getPullMock = jest.fn<any>().mockResolvedValue({data: {labels: []}});
+const listFilesMergeMock = jest.fn<any>().mockReturnValue({});
+
+const coreGetInputMock = jest.fn<any>();
+const coreGetMultilineInputMock = jest.fn<any>();
+const coreGetBooleanInputMock = jest.fn<any>();
+const coreErrorMock = jest.fn<any>();
+const coreWarningMock = jest.fn<any>();
+const coreSetFailedMock = jest.fn<any>();
+const setOutputSpy = jest.fn<any>();
+
+const mockGithubContext: any = {
+  payload: {
+    pull_request: {
+      number: 123,
+      head: {ref: 'head-branch-name'},
+      base: {ref: 'base-branch-name'}
+    }
+  },
+  repo: {owner: 'monalisa', repo: 'helloworld'}
+};
+
+jest.unstable_mockModule('@actions/core', () => ({
+  getInput: coreGetInputMock,
+  getMultilineInput: coreGetMultilineInputMock,
+  getBooleanInput: coreGetBooleanInputMock,
+  setOutput: setOutputSpy,
+  setFailed: coreSetFailedMock,
+  error: coreErrorMock,
+  warning: coreWarningMock,
+  info: jest.fn(),
+  debug: jest.fn()
+}));
+
+jest.unstable_mockModule('@actions/github', () => ({
+  context: mockGithubContext,
+  getOctokit: jest.fn(() => ({
+    rest: {
+      issues: {setLabels: setLabelsMock},
+      repos: {getContent: reposMock},
+      pulls: {
+        get: getPullMock,
+        listFiles: {endpoint: {merge: listFilesMergeMock}}
+      }
+    },
+    paginate: paginateMock
+  }))
+}));
+
+const {run} = await import('../src/labeler.js');
 
-const gh = github.getOctokit('_');
-const setLabelsMock = jest.spyOn(gh.rest.issues, 'setLabels');
-const reposMock = jest.spyOn(gh.rest.repos, 'getContent');
-const paginateMock = jest.spyOn(gh, 'paginate');
-const getPullMock = jest.spyOn(gh.rest.pulls, 'get');
 const readFileSyncMock = jest.spyOn(fs, 'readFileSync');
 const existsSyncMock = jest.spyOn(fs, 'existsSync');
-const coreErrorMock = jest.spyOn(core, 'error');
-const coreWarningMock = jest.spyOn(core, 'warning');
-const coreSetFailedMock = jest.spyOn(core, 'setFailed');
-const setOutputSpy = jest.spyOn(core, 'setOutput');
 
 class HttpError extends Error {
   constructor(message: string) {
@@ -59,20 +111,27 @@ const configureInput = (
     'pr-number': string[];
   }>
 ) => {
-  jest
-    .spyOn(core, 'getInput')
-    .mockImplementation((name: string, ...opts) => mockInput[name]);
-  jest
-    .spyOn(core, 'getMultilineInput')
-    .mockImplementation((name: string, ...opts) => mockInput[name]);
-  jest
-    .spyOn(core, 'getBooleanInput')
-    .mockImplementation((name: string, ...opts) => mockInput[name]);
+  coreGetInputMock.mockImplementation(
+    (name: unknown) => mockInput[name as keyof typeof mockInput]
+  );
+  coreGetMultilineInputMock.mockImplementation(
+    (name: unknown) => mockInput[name as keyof typeof mockInput]
+  );
+  coreGetBooleanInputMock.mockImplementation(
+    (name: unknown) => mockInput[name as keyof typeof mockInput]
+  );
 };
 
-afterAll(() => jest.restoreAllMocks());
+afterAll(async () => {
+  jest.restoreAllMocks();
+});
 
 describe('run', () => {
+  beforeEach(() => {
+    getPullMock.mockResolvedValue({data: {labels: []}} as any);
+    mockGithubContext.payload.pull_request.head = {ref: 'head-branch-name'};
+    mockGithubContext.payload.pull_request.base = {ref: 'base-branch-name'};
+  });
   it('(with dot: false) adds labels to PRs that match our glob patterns', async () => {
     configureInput({});
     usingLabelerConfigYaml('only_pdfs.yml');
@@ -169,7 +228,7 @@ describe('run', () => {
 
   it('adds labels based on the branch names that match the regexp pattern', async () => {
     configureInput({});
-    github.context.payload.pull_request!.head = {ref: 'test/testing-time'};
+    mockGithubContext.payload.pull_request.head = {ref: 'test/testing-time'};
     usingLabelerConfigYaml('branches.yml');
     await run();
 
@@ -187,7 +246,7 @@ describe('run', () => {
 
   it('adds multiple labels based on branch names that match different regexp patterns', async () => {
     configureInput({});
-    github.context.payload.pull_request!.head = {
+    mockGithubContext.payload.pull_request.head = {
       ref: 'test/feature/123'
     };
     usingLabelerConfigYaml('branches.yml');
@@ -213,7 +272,7 @@ describe('run', () => {
 
   it('can support multiple branches by batching', async () => {
     configureInput({});
-    github.context.payload.pull_request!.head = {ref: 'fix/123'};
+    mockGithubContext.payload.pull_request.head = {ref: 'fix/123'};
     usingLabelerConfigYaml('branches.yml');
     await run();
 
@@ -231,7 +290,7 @@ describe('run', () => {
 
   it('can support multiple branches by providing an array', async () => {
     configureInput({});
-    github.context.payload.pull_request!.head = {ref: 'array/123'};
+    mockGithubContext.payload.pull_request.head = {ref: 'array/123'};
     usingLabelerConfigYaml('branches.yml');
     await run();
 
@@ -644,7 +703,7 @@ describe('run', () => {
   describe('changed-files-labels-limit', () => {
     it('applies all labels when count is within limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('limit_3.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -667,7 +726,7 @@ describe('run', () => {
 
     it('skips changed-files labels when count exceeds limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('limit_2.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -686,7 +745,7 @@ describe('run', () => {
 
     it('still applies branch-based labels when changed-files limit is exceeded', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'test/some-feature'};
+      mockGithubContext.payload.pull_request.head = {ref: 'test/some-feature'};
       usingLabelerConfigYaml('limit_1.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -711,7 +770,7 @@ describe('run', () => {
 
     it('applies all labels when no limit is set', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('mixed_labels.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -736,7 +795,7 @@ describe('run', () => {
 
     it('does not count preexisting labels toward the limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('limit_2.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -763,7 +822,7 @@ describe('run', () => {
 
     it('skips new labels when new count exceeds limit even with preexisting', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('limit_2.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -784,7 +843,7 @@ describe('run', () => {
 
     it('applies labels when new count equals the limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('limit_2.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -807,7 +866,7 @@ describe('run', () => {
 
     it('skips all changed-files labels when limit is 0', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'test/some-feature'};
+      mockGithubContext.payload.pull_request.head = {ref: 'test/some-feature'};
       usingLabelerConfigYaml('limit_0.yml');
       mockGitHubResponseChangedFiles('components/a/file.ts');
       getPullMock.mockResolvedValue(<any>{
@@ -831,7 +890,7 @@ describe('run', () => {
       // a "changed-files label" and subject to the limit, even if it matches
       // via the branch rule
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'test/some-feature'};
+      mockGithubContext.payload.pull_request.head = {ref: 'test/some-feature'};
       usingLabelerConfigYaml('mixed_rules.yml');
       mockGitHubResponseChangedFiles('unrelated/file.ts');
       getPullMock.mockResolvedValue(<any>{
@@ -856,7 +915,7 @@ describe('run', () => {
   describe('max-files-changed', () => {
     it('applies labels when changed files count is within limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('max_files_5.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file.ts',
@@ -880,7 +939,7 @@ describe('run', () => {
 
     it('skips file-based labels when changed files exceed limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('max_files_5.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file1.ts',
@@ -902,7 +961,7 @@ describe('run', () => {
 
     it('applies labels when changed files count equals limit', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('max_files_5.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file1.ts',
@@ -928,7 +987,7 @@ describe('run', () => {
 
     it('still applies branch-based labels when max-files-changed is exceeded', async () => {
       configureInput({});
-      github.context.payload.pull_request!.head = {ref: 'test/some-feature'};
+      mockGithubContext.payload.pull_request.head = {ref: 'test/some-feature'};
       usingLabelerConfigYaml('max_files_with_branch.yml');
       mockGitHubResponseChangedFiles(
         'components/a/file1.ts',
@@ -954,7 +1013,7 @@ describe('run', () => {
 
     it('preserves preexisting changed-files labels with sync-labels when max-files-changed is exceeded', async () => {
       configureInput({'sync-labels': true});
-      github.context.payload.pull_request!.head = {ref: 'main'};
+      mockGithubContext.payload.pull_request.head = {ref: 'main'};
       usingLabelerConfigYaml('max_files_5.yml');
       mockGitHubResponseChangedFiles(
         'unrelated/file1.ts',