feat: add secondary entrypoint schematic

packages/schematics/angular/collection.json

@@ -117,6 +117,12 @@
       "schema": "./library/schema.json",
       "description": "Generate a library project for Angular."
     },
+    "library-secondary-entrypoint": {
+      "aliases": ["secondary"],
+      "factory": "./secondary-entrypoint",
+      "schema": "./secondary-entrypoint/schema.json",
+      "description": "Generate a secondary-entrypoint in a library project for Angular."
+    },
     "web-worker": {
       "factory": "./web-worker",
       "schema": "./web-worker/schema.json",

packages/schematics/angular/secondary-entrypoint/files/README.md.template

@@ -0,0 +1,3 @@
+# <%= secondaryEntryPoint %>
+
+Secondary entry point of `<%= mainEntryPoint %>`. It can be used by importing from `<%= secondaryEntryPoint %>`.

packages/schematics/angular/secondary-entrypoint/files/ng-package.json.template

@@ -0,0 +1,6 @@
+{
+  "$schema": "<%= relativePathToWorkspaceRoot %>/node_modules/ng-packagr/ng-package.schema.json",
+  "lib": {
+    "entryFile": "src/<%= entryFile %>.ts"
+  }
+}

packages/schematics/angular/secondary-entrypoint/files/src/__entryFile__.ts.template

@@ -0,0 +1,5 @@
+/*
+ * Public API Surface of <%= dasherize(name) %>
+ */
+
+export const greeting = 'Hello Angular World!';

packages/schematics/angular/secondary-entrypoint/index.ts

@@ -0,0 +1,96 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+import {
+  Rule,
+  SchematicsException,
+  Tree,
+  apply,
+  applyTemplates,
+  chain,
+  mergeWith,
+  move,
+  strings,
+  url,
+} from '@angular-devkit/schematics';
+import { JSONFile } from '../utility/json-file';
+import { latestVersions } from '../utility/latest-versions';
+import { relativePathToWorkspaceRoot } from '../utility/paths';
+import { buildDefaultPath, getWorkspace } from '../utility/workspace';
+import { ProjectType } from '../utility/workspace-models';
+import { Schema as LibraryOptions } from './schema';
+
+function updateTsConfig(packageName: string, ...paths: string[]) {
+  return (host: Tree) => {
+    if (!host.exists('tsconfig.json')) {
+      return host;
+    }
+
+    const file = new JSONFile(host, 'tsconfig.json');
+    const jsonPath = ['compilerOptions', 'paths', packageName];
+    const value = file.get(jsonPath);
+    file.modify(jsonPath, Array.isArray(value) ? [...value, ...paths] : paths);
+  };
+}
+
+export default function (options: LibraryOptions): Rule {
+  return async (host: Tree) => {
+    return async (host: Tree) => {
+      const workspace = await getWorkspace(host);
+      const project = workspace.projects.get(options.project);
+
+      if (!project) {
+        throw new SchematicsException(`Project "${options.project}" does not exist.`);
+      }
+
+      if (project?.extensions.projectType !== ProjectType.Library) {
+        throw new SchematicsException(
+          `Secondary Entrypoint schematic requires a project type of "library".`,
+        );
+      }
+
+      const path = buildDefaultPath(project);
+      const libDir = `${path}/${options.name}`;
+      const pkgPath = `${project.root}/package.json`;
+
+      const pkg = host.readJson(pkgPath) as { name: string } | null;
+      if (pkg === null) {
+        throw new SchematicsException('Could not find package.json');
+      }
+
+      const mainEntryPoint = pkg.name;
+      const secondaryEntryPoint = `${mainEntryPoint}/${options.name}`;
+
+      let folderName = mainEntryPoint.startsWith('@') ? mainEntryPoint.slice(1) : mainEntryPoint;
+      if (/[A-Z]/.test(folderName)) {
+        folderName = strings.dasherize(folderName);
+      }
+
+      const distRoot = `dist/${folderName}/${options.name}`;
+
+      const templateSource = apply(url('./files'), [
+        applyTemplates({
+          ...strings,
+          ...options,
+          mainEntryPoint,
+          secondaryEntryPoint,
+          relativePathToWorkspaceRoot: relativePathToWorkspaceRoot(libDir),
+          packageName: options.name,
+          angularLatestVersion: latestVersions.Angular.replace(/~|\^/, ''),
+          tsLibLatestVersion: latestVersions['tslib'].replace(/~|\^/, ''),
+        }),
+        move(libDir),
+      ]);
+
+      return chain([
+        mergeWith(templateSource),
+        updateTsConfig(secondaryEntryPoint, './' + distRoot),
+      ]);
+    };
+  };
+}

packages/schematics/angular/secondary-entrypoint/index_spec.ts

@@ -0,0 +1,164 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+import { SchematicTestRunner, UnitTestTree } from '@angular-devkit/schematics/testing';
+import { Schema as LibraryOptions } from '../library/schema';
+import { Schema as WorkspaceOptions } from '../workspace/schema';
+import { Schema as GenerateLibrarySchema } from './schema';
+import { parse as parseJson } from 'jsonc-parser';
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+function getJsonFileContent(tree: UnitTestTree, path: string): any {
+  return parseJson(tree.readContent(path).toString());
+}
+
+describe('Secondary Entrypoint Schematic', () => {
+  const schematicRunner = new SchematicTestRunner(
+    '@schematics/ng_packagr',
+    require.resolve('../collection.json'),
+  );
+  const defaultOptions: GenerateLibrarySchema = {
+    name: 'foo-secondary',
+    project: 'foo',
+  };
+
+  const workspaceOptions: WorkspaceOptions = {
+    name: 'workspace',
+    newProjectRoot: 'projects',
+
+    version: '6.0.0',
+  };
+  const libaryOptions: LibraryOptions = {
+    name: 'foo',
+    entryFile: 'my-index',
+    standalone: true,
+    skipPackageJson: false,
+    skipTsConfig: false,
+    skipInstall: false,
+  };
+
+  let workspaceTree: UnitTestTree;
+  beforeEach(async () => {
+    workspaceTree = await schematicRunner.runSchematic('workspace', workspaceOptions);
+  });
+
+  it('should create correct files', async () => {
+    workspaceTree = await schematicRunner.runSchematic('library', libaryOptions, workspaceTree);
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions },
+      workspaceTree,
+    );
+    const files = tree.files;
+
+    expect(files).toEqual(
+      jasmine.arrayContaining([
+        '/projects/foo/src/lib/foo-secondary/README.md',
+        '/projects/foo/src/lib/foo-secondary/ng-package.json',
+        '/projects/foo/src/lib/foo-secondary/src/public-api.ts',
+      ]),
+    );
+  });
+
+  it('should set correct main and secondary entrypoints in the README', async () => {
+    workspaceTree = await schematicRunner.runSchematic('library', libaryOptions, workspaceTree);
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions },
+      workspaceTree,
+    );
+    const content = tree.readContent('/projects/foo/src/lib/foo-secondary/README.md');
+    expect(content).toMatch('# foo/foo-secondary');
+  });
+
+  it('should set a custom entryfile', async () => {
+    workspaceTree = await schematicRunner.runSchematic('library', libaryOptions, workspaceTree);
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions, entryFile: 'my-index' },
+      workspaceTree,
+    );
+    const files = tree.files;
+    expect(files).toEqual(
+      jasmine.arrayContaining([
+        '/projects/foo/src/lib/foo-secondary/README.md',
+        '/projects/foo/src/lib/foo-secondary/ng-package.json',
+        '/projects/foo/src/lib/foo-secondary/src/my-index.ts',
+      ]),
+    );
+  });
+
+  it('should handle scope packages', async () => {
+    workspaceTree = await schematicRunner.runSchematic(
+      'library',
+      { ...libaryOptions, name: '@scope/package' },
+      workspaceTree,
+    );
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions, name: 'testing', project: '@scope/package' },
+      workspaceTree,
+    );
+    const files = tree.files;
+    expect(files).toEqual(
+      jasmine.arrayContaining([
+        '/projects/scope/package/src/lib/testing/README.md',
+        '/projects/scope/package/src/lib/testing/ng-package.json',
+        '/projects/scope/package/src/lib/testing/src/public-api.ts',
+      ]),
+    );
+  });
+
+  it(`should add paths mapping to the tsconfig`, async () => {
+    workspaceTree = await schematicRunner.runSchematic(
+      'library',
+      { ...libaryOptions, name: '@scope/package' },
+      workspaceTree,
+    );
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions, name: 'testing', project: '@scope/package' },
+      workspaceTree,
+    );
+
+    const tsConfigJson = getJsonFileContent(tree, 'tsconfig.json');
+    expect(tsConfigJson.compilerOptions.paths['@scope/package/testing']).toEqual([
+      './dist/scope/package/testing',
+    ]);
+  });
+
+  it(`should append to existing paths mappings`, async () => {
+    workspaceTree = await schematicRunner.runSchematic(
+      'library',
+      { ...libaryOptions, name: '@scope/package' },
+      workspaceTree,
+    );
+    workspaceTree.overwrite(
+      'tsconfig.json',
+      JSON.stringify({
+        compilerOptions: {
+          paths: {
+            'unrelated': ['./something/else.ts'],
+            '@scope/package/testing': ['libs/*'],
+          },
+        },
+      }),
+    );
+    const tree = await schematicRunner.runSchematic(
+      'secondary',
+      { ...defaultOptions, name: 'testing', project: '@scope/package' },
+      workspaceTree,
+    );
+
+    const tsConfigJson = getJsonFileContent(tree, 'tsconfig.json');
+    expect(tsConfigJson.compilerOptions.paths['@scope/package/testing']).toEqual([
+      'libs/*',
+      './dist/scope/package/testing',
+    ]);
+  });
+});

packages/schematics/angular/secondary-entrypoint/schema.json

@@ -0,0 +1,34 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema",
+  "$id": "SchematicsLibrary",
+  "title": "Secondary Entrypoint Schema",
+  "type": "object",
+  "description": "Creates a secondary entrypoint in a library project in a project.",
+  "additionalProperties": false,
+  "properties": {
+    "name": {
+      "type": "string",
+      "description": "The name of the library.",
+      "pattern": "^(?:@[a-zA-Z0-9-*~][a-zA-Z0-9-*._~]*/)?[a-zA-Z0-9-~][a-zA-Z0-9-._~]*$",
+      "$default": {
+        "$source": "argv",
+        "index": 0
+      },
+      "x-prompt": "What name would you like to use for the secondary entrypoint?"
+    },
+    "project": {
+      "type": "string",
+      "description": "The name of the project.",
+      "$default": {
+        "$source": "projectName"
+      }
+    },
+    "entryFile": {
+      "type": "string",
+      "format": "path",
+      "description": "The path at which to create the library's secondary public API file, relative to the workspace root.",
+      "default": "public-api"
+    }
+  },
+  "required": ["name", "project"]
+}