Add isvalid {N} project method (#2602)

We need a method in the public API to check if a directory contains valid NativeScript project.

Author: TsvetanMilanov

lib/definitions/project.d.ts

@@ -44,6 +44,13 @@ interface IProjectService {
 	 * @returns {Promise<void>}
 	 */
 	createProject(projectSettings: IProjectSettings): Promise<void>;
+
+	/**
+	 * Checks if the specified project is valid NativeScript project.
+	 * @param {string} pathToProject Directory to check.
+	 * @returns {boolean} returns true if the project is valid NativeScript project.
+	 */
+	isValidNativeScriptProject(pathToProject?: string): boolean;
 }
 
 interface IProjectData {

lib/services/project-service.ts

@@ -1,14 +1,15 @@
 import * as constants from "../constants";
 import * as path from "path";
 import * as shelljs from "shelljs";
-import { exportedPromise } from "../common/decorators";
+import { exportedPromise, exported } from "../common/decorators";
 
 export class ProjectService implements IProjectService {
 
 	constructor(private $npm: INodePackageManager,
 		private $errors: IErrors,
 		private $fs: IFileSystem,
 		private $logger: ILogger,
+		private $projectData: IProjectData,
 		private $projectDataService: IProjectDataService,
 		private $projectHelper: IProjectHelper,
 		private $projectNameService: IProjectNameService,
@@ -66,6 +67,17 @@ export class ProjectService implements IProjectService {
 		this.$logger.printMarkdown("Project `%s` was successfully created.", projectName);
 	}
 
+	@exported("projectService")
+	public isValidNativeScriptProject(pathToProject?: string): boolean {
+		try {
+			this.$projectData.initializeProjectData(pathToProject);
+		} catch (e) {
+			return false;
+		}
+
+		return true;
+	}
+
 	private getDataFromJson(templatePath: string): any {
 		let templatePackageJsonPath = path.join(templatePath, constants.PACKAGE_JSON_FILE_NAME);
 		if (this.$fs.exists(templatePackageJsonPath)) {

test/project-commands.ts

@@ -14,6 +14,10 @@ class ProjectServiceMock implements IProjectService {
 		selectedTemplateName = projectOptions.template;
 		isProjectCreated = true;
 	}
+
+	isValidNativeScriptProject(pathToProject?: string): boolean {
+		return true;
+	}
 }
 
 class ProjectNameValidatorMock implements IProjectNameValidator {

test/project-service.ts

@@ -110,6 +110,7 @@ class ProjectIntegrationTest {
 		this.testInjector.register("projectHelper", ProjectHelperLib.ProjectHelper);
 		this.testInjector.register("projectTemplatesService", ProjectTemplatesService);
 		this.testInjector.register("projectNameValidator", mockProjectNameValidator);
+		this.testInjector.register("projectData", {});
 
 		this.testInjector.register("fs", FileSystem);
 		this.testInjector.register("projectDataService", ProjectDataServiceLib.ProjectDataService);