feat(@schematics/angular): add generation for resolvers

closes: #17569

packages/schematics/angular/collection.json

@@ -60,6 +60,12 @@
       "description": "Create a guard.",
       "schema": "./guard/schema.json"
     },
+    "resolver": {
+      "aliases": [ "r" ],
+      "factory": "./resolver",
+      "description": "Create a resolver.",
+      "schema": "./resolver/schema.json"
+    },
     "interceptor": {
       "factory": "./interceptor",
       "description": "Create an interceptor.",

packages/schematics/angular/resolver/files/__name@dasherize__.resolver.spec.ts.template

@@ -0,0 +1,16 @@
+import { TestBed } from '@angular/core/testing';
+
+import { <%= classify(name) %>Resolver } from './<%= dasherize(name) %>.resolver';
+
+describe('<%= classify(name) %>Resolver', () => {
+  let resolver: <%= classify(name) %>Resolver;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({});
+    resolver = TestBed.inject(<%= classify(name) %>Resolver);
+  });
+
+  it('should be created', () => {
+    expect(resolver).toBeTruthy();
+  });
+});

packages/schematics/angular/resolver/files/__name@dasherize__.resolver.ts.template

@@ -0,0 +1,16 @@
+import { Injectable } from '@angular/core';
+import {
+  Router, Resolve,
+  RouterStateSnapshot,
+  ActivatedRouteSnapshot
+} from '@angular/router';
+import { Observable, of } from 'rxjs';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class <%= classify(name) %>Resolver implements Resolve<boolean> {
+  resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> {
+    return of(true);
+  }
+}

packages/schematics/angular/resolver/index.ts

@@ -0,0 +1,49 @@
+/**
+* @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 { strings } from '@angular-devkit/core';
+import {
+  Rule,
+  Tree,
+  apply,
+  applyTemplates,
+  chain,
+  filter,
+  mergeWith,
+  move,
+  noop,
+  url,
+} from '@angular-devkit/schematics';
+import { parseName } from '../utility/parse-name';
+import { createDefaultPath } from '../utility/workspace';
+import { Schema } from './schema';
+
+
+export default function (options: Schema): Rule {
+  return async (host: Tree) => {
+    if (options.path === undefined) {
+      options.path = await createDefaultPath(host, options.project as string);
+    }
+
+    const parsedPath = parseName(options.path, options.name);
+    options.name = parsedPath.name;
+    options.path = parsedPath.path;
+
+    const templateSource = apply(url('./files'), [
+      options.skipTests ? filter(path => !path.endsWith('.spec.ts.template')) : noop(),
+      applyTemplates({
+        ...strings,
+        ...options,
+      }),
+      move(parsedPath.path + (options.flat ? '' : '/' + strings.dasherize(options.name))),
+    ]);
+
+    return chain([
+      mergeWith(templateSource),
+    ]);
+  };
+}

packages/schematics/angular/resolver/index_spec.ts

@@ -0,0 +1,80 @@
+/**
+ * @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 { SchematicTestRunner, UnitTestTree } from '@angular-devkit/schematics/testing';
+import { Schema as ApplicationOptions } from '../application/schema';
+import { Schema as WorkspaceOptions } from '../workspace/schema';
+import { Schema } from './schema';
+
+describe('resolver Schematic', () => {
+  const schematicRunner = new SchematicTestRunner(
+    '@schematics/angular',
+    require.resolve('../collection.json'),
+  );
+  const defaultOptions: Schema = {
+    name: 'foo',
+    flat: true,
+    project: 'bar',
+  };
+  const workspaceOptions: WorkspaceOptions = {
+    name: 'workspace',
+    newProjectRoot: 'projects',
+    version: '6.0.0',
+  };
+
+  const appOptions: ApplicationOptions = {
+    name: 'bar',
+    inlineStyle: false,
+    inlineTemplate: false,
+    routing: false,
+    skipTests: false,
+    skipPackageJson: false,
+  };
+  let appTree: UnitTestTree;
+  beforeEach(async () => {
+    appTree = await schematicRunner.runSchematicAsync('workspace', workspaceOptions).toPromise();
+    appTree = await schematicRunner.runSchematicAsync('application', appOptions, appTree)
+      .toPromise();
+  });
+
+  it('should create a resolver', async () => {
+    const tree = await schematicRunner.runSchematicAsync('resolver', defaultOptions, appTree)
+      .toPromise();
+    const files = tree.files;
+    expect(files).toContain('/projects/bar/src/app/foo.resolver.spec.ts');
+    expect(files).toContain('/projects/bar/src/app/foo.resolver.ts');
+  });
+
+  it('should respect the skipTests flag', async () => {
+    const options = { ...defaultOptions, skipTests: true };
+
+    const tree = await schematicRunner.runSchematicAsync('resolver', options, appTree)
+      .toPromise();
+    const files = tree.files;
+    expect(files).not.toContain('/projects/bar/src/app/foo.resolver.spec.ts');
+    expect(files).toContain('/projects/bar/src/app/foo.resolver.ts');
+  });
+
+  it('should respect the flat flag', async () => {
+    const options = { ...defaultOptions, flat: false };
+
+    const tree = await schematicRunner.runSchematicAsync('resolver', options, appTree)
+      .toPromise();
+    const files = tree.files;
+    expect(files).toContain('/projects/bar/src/app/foo/foo.resolver.spec.ts');
+    expect(files).toContain('/projects/bar/src/app/foo/foo.resolver.ts');
+  });
+
+  it('should respect the sourceRoot value', async () => {
+    const config = JSON.parse(appTree.readContent('/angular.json'));
+    config.projects.bar.sourceRoot = 'projects/bar/custom';
+    appTree.overwrite('/angular.json', JSON.stringify(config, null, 2));
+    appTree = await schematicRunner.runSchematicAsync('resolver', defaultOptions, appTree)
+      .toPromise();
+    expect(appTree.files).toContain('/projects/bar/custom/app/foo.resolver.ts');
+  });
+});

packages/schematics/angular/resolver/schema.json

@@ -0,0 +1,45 @@
+{
+  "$schema": "http://json-schema.org/schema",
+  "id": "SchematicsAngularResolver",
+  "title": "Angular resolver Options Schema",
+  "type": "object",
+  "description": "Generates a new, generic resolver definition in the given or default project.",
+  "properties": {
+    "name": {
+      "type": "string",
+      "description": "The name of the new resolver.",
+      "$default": {
+        "$source": "argv",
+        "index": 0
+      },
+      "x-prompt": "What name would you like to use for the resolver?"
+    },
+    "skipTests": {
+      "type": "boolean",
+      "description": "When true, does not create \"spec.ts\" test files for the new resolver.",
+      "default": false,
+      "x-user-analytics": 12
+    },
+    "flat": {
+      "type": "boolean",
+      "description": "When true (the default), creates the new files at the top level of the current project.",
+      "default": true
+    },
+    "path": {
+      "type": "string",
+      "format": "path",
+      "description": "The path at which to create the interface that defines the resolver, relative to the current workspace.",
+      "visible": false
+    },
+    "project": {
+      "type": "string",
+      "description": "The name of the project.",
+      "$default": {
+        "$source": "projectName"
+      }
+    }
+  },
+  "required": [
+    "name"
+  ]
+}