test(amplify-category-custom): add tests for custom build script support

Add tests for the hasBuildScript() function and the new logic that
allows custom resources to define their own build script in package.json.

New test cases:
- Run install and tsc separately when no build script defined
- Run install and tsc when package.json has scripts but no build script
- Run build script when package.json has scripts.build defined
- Not call install or tsc separately when build script is defined
- Fall back to install+tsc when package.json does not exist

Author: danrivett

packages/amplify-category-custom/src/__tests__/utils/build-custom-resources.test.ts

@@ -1,5 +1,6 @@
-import { $TSContext } from '@aws-amplify/amplify-cli-core';
+import { $TSContext, JSONUtilities } from '@aws-amplify/amplify-cli-core';
 import execa from 'execa';
+import * as fs from 'fs-extra';
 import { buildCustomResources } from '../../utils/build-custom-resources';
 
 jest.mock('@aws-amplify/amplify-cli-core');
@@ -8,15 +9,10 @@ jest.mock('../../utils/dependency-management-utils');
 jest.mock('../../utils/generate-cfn-from-cdk');
 jest.mock('execa');
 jest.mock('ora');
+jest.mock('fs-extra');
 
-jest.mock('fs-extra', () => ({
-  readFileSync: jest.fn().mockReturnValue('mockCode'),
-  existsSync: jest.fn().mockReturnValue(true),
-  ensureDirSync: jest.fn().mockReturnValue(true),
-  ensureDir: jest.fn(),
-  writeFileSync: jest.fn().mockReturnValue(true),
-  writeFile: jest.fn(),
-}));
+const fs_mock = fs as jest.Mocked<typeof fs>;
+const JSONUtilities_mock = JSONUtilities as jest.Mocked<typeof JSONUtilities>;
 
 jest.mock('ora', () => () => ({
   start: jest.fn(),
@@ -34,7 +30,15 @@ jest.mock('../../utils/generate-cfn-from-cdk', () => ({
 }));
 
 jest.mock('@aws-amplify/amplify-cli-core', () => ({
-  getPackageManager: jest.fn().mockResolvedValue('npm'),
+  getPackageManager: jest.fn().mockResolvedValue({
+    packageManager: 'npm',
+    executable: 'npm',
+    runner: 'npx',
+    lockFile: 'package-lock.json',
+    displayValue: 'NPM',
+    getRunScriptArgs: jest.fn(),
+    getInstallArgs: jest.fn(),
+  }),
   pathManager: {
     getBackendDirPath: jest.fn().mockReturnValue('mockTargetDir'),
   },
@@ -44,13 +48,31 @@ jest.mock('@aws-amplify/amplify-cli-core', () => ({
     stringify: jest.fn(),
   },
   skipHooks: jest.fn().mockReturnValue(false),
+  AmplifyError: class AmplifyError extends Error {
+    constructor(name: string, options: { message: string }) {
+      super(options.message);
+      this.name = name;
+    }
+  },
 }));
 
 describe('build custom resources scenarios', () => {
   let mockContext: $TSContext;
 
   beforeEach(() => {
     jest.clearAllMocks();
+
+    // Default fs mocks
+    (fs_mock.existsSync as jest.Mock).mockReturnValue(true);
+    (fs_mock.readFileSync as jest.Mock).mockReturnValue('mockCode');
+    (fs_mock.ensureDirSync as jest.Mock).mockReturnValue(undefined);
+    (fs_mock.ensureDir as jest.Mock).mockResolvedValue(undefined);
+    (fs_mock.writeFileSync as jest.Mock).mockReturnValue(undefined);
+    (fs_mock.writeFile as jest.Mock).mockResolvedValue(undefined);
+
+    // Default: no build script in package.json
+    JSONUtilities_mock.readJson.mockReturnValue({});
+
     mockContext = {
       amplify: {
         openEditor: jest.fn(),
@@ -72,10 +94,93 @@ describe('build custom resources scenarios', () => {
     } as unknown as $TSContext;
   });
 
-  it('build all resources', async () => {
-    await buildCustomResources(mockContext);
+  describe('default behavior (no build script)', () => {
+    it('should run install and tsc separately when no build script defined', async () => {
+      // No build script in package.json
+      JSONUtilities_mock.readJson.mockReturnValue({});
+
+      await buildCustomResources(mockContext);
+
+      // 2 for npm install and 2 for tsc build (1 per resource)
+      expect(execa.sync).toBeCalledTimes(4);
+
+      // First resource: install then tsc
+      expect(execa.sync).toHaveBeenNthCalledWith(1, 'npm', ['install'], expect.objectContaining({ stdio: 'pipe' }));
+      expect(execa.sync).toHaveBeenNthCalledWith(2, 'npx', ['tsc'], expect.objectContaining({ stdio: 'pipe' }));
+
+      // Second resource: install then tsc
+      expect(execa.sync).toHaveBeenNthCalledWith(3, 'npm', ['install'], expect.objectContaining({ stdio: 'pipe' }));
+      expect(execa.sync).toHaveBeenNthCalledWith(4, 'npx', ['tsc'], expect.objectContaining({ stdio: 'pipe' }));
+    });
+
+    it('should run install and tsc when package.json has scripts but no build script', async () => {
+      // package.json with scripts but no build script
+      JSONUtilities_mock.readJson.mockReturnValue({
+        scripts: {
+          test: 'jest',
+          lint: 'eslint .',
+        },
+      });
+
+      await buildCustomResources(mockContext);
+
+      // Should still run install + tsc for each resource
+      expect(execa.sync).toBeCalledTimes(4);
+      expect(execa.sync).toHaveBeenNthCalledWith(1, 'npm', ['install'], expect.objectContaining({ stdio: 'pipe' }));
+    });
+  });
+
+  describe('custom build script behavior', () => {
+    it('should run build script when package.json has scripts.build defined', async () => {
+      // package.json with build script
+      JSONUtilities_mock.readJson.mockReturnValue({
+        scripts: {
+          build: 'pnpm install --ignore-workspace && tsc',
+        },
+      });
+
+      await buildCustomResources(mockContext);
+
+      // Only 2 calls (1 per resource) for 'npm run build'
+      expect(execa.sync).toBeCalledTimes(2);
+
+      expect(execa.sync).toHaveBeenNthCalledWith(1, 'npm', ['run', 'build'], expect.objectContaining({ stdio: 'pipe' }));
+      expect(execa.sync).toHaveBeenNthCalledWith(2, 'npm', ['run', 'build'], expect.objectContaining({ stdio: 'pipe' }));
+    });
+
+    it('should not call install or tsc separately when build script is defined', async () => {
+      JSONUtilities_mock.readJson.mockReturnValue({
+        scripts: {
+          build: 'custom-build-command',
+        },
+      });
+
+      await buildCustomResources(mockContext);
+
+      // Verify install and tsc are NOT called
+      const calls = (execa.sync as jest.Mock).mock.calls;
+      const hasInstallCall = calls.some((call) => call[1]?.[0] === 'install');
+      const hasTscCall = calls.some((call) => call[1]?.[0] === 'tsc');
+
+      expect(hasInstallCall).toBe(false);
+      expect(hasTscCall).toBe(false);
+    });
+  });
+
+  describe('hasBuildScript edge cases', () => {
+    it('should fall back to install+tsc when package.json does not exist', async () => {
+      // package.json doesn't exist for the custom resource
+      (fs_mock.existsSync as jest.Mock).mockImplementation((filePath: unknown) => {
+        if (typeof filePath === 'string' && filePath.includes('package.json')) {
+          return false;
+        }
+        return true;
+      });
+
+      await buildCustomResources(mockContext);
 
-    // 2 for npm install and 2 for tsc build (1 per resource)
-    expect(execa.sync).toBeCalledTimes(4);
+      // Should run install + tsc (default behavior)
+      expect(execa.sync).toBeCalledTimes(4);
+    });
   });
 });