test: add tests to schematic-cli

Author: alan-agius4

packages/angular_devkit/schematics_cli/bin/schematics_spec.ts

@@ -0,0 +1,54 @@
+/**
+ * @license
+ * Copyright Google Inc. 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.io/license
+ */
+
+import { main } from './schematics';
+
+// We only care about the write method in these mocks of NodeJS.WriteStream.
+class MockWriteStream {
+  lines: string[] = [];
+  write(str: string) {
+    // Strip color control characters.
+    this.lines.push(str.replace(/[^\x20-\x7F]\[\d+m/g, ''));
+
+    return true;
+  }
+}
+
+describe('schematics-cli binary', () => {
+  let stdout: MockWriteStream, stderr: MockWriteStream;
+
+  beforeEach(() => {
+    stdout = new MockWriteStream();
+    stderr = new MockWriteStream();
+  });
+
+  it('list-schematics works', async () => {
+    const args = ['--list-schematics'];
+    const res = await main({ args, stdout, stderr });
+    expect(stdout.lines).toMatch(/blank/);
+    expect(stdout.lines).toMatch(/schematic/);
+    expect(res).toEqual(0);
+  });
+
+  it('dry-run works', async () => {
+    const args = ['blank', 'foo', '--dry-run'];
+    const res = await main({ args, stdout, stderr });
+    expect(stdout.lines).toMatch(/CREATE \/foo\/README.md/);
+    expect(stdout.lines).toMatch(/CREATE \/foo\/.gitignore/);
+    expect(stdout.lines).toMatch(/CREATE \/foo\/src\/foo\/index.ts/);
+    expect(stdout.lines).toMatch(/CREATE \/foo\/src\/foo\/index_spec.ts/);
+    expect(res).toEqual(0);
+  });
+
+  it('error when no name is provided', async () => {
+    const args = ['blank'];
+    const res = await main({ args, stdout, stderr });
+    expect(stderr.lines).toMatch(/Error: name option is required/);
+    expect(res).toEqual(1);
+  });
+});