Merge pull request #3960 from NativeScript/fatme/fix-preview-nsconfig

fix: works correctly with projects with `.nsconfig` file on `tns preview` command

Author: rosen-vladimirov

lib/services/livesync/playground/preview-app-livesync-service.ts

@@ -110,11 +110,10 @@ export class PreviewAppLiveSyncService implements IPreviewAppLiveSyncService {
 	}
 
 	private getFilesPayload(platformData: IPlatformData, projectData: IProjectData, files?: string[]): FilesPayload {
-		const appFolderPath = path.join(projectData.projectDir, APP_FOLDER_NAME);
 		const platformsAppFolderPath = path.join(platformData.appDestinationDirectoryPath, APP_FOLDER_NAME);
 
 		if (files && files.length) {
-			files = files.map(file => path.join(platformsAppFolderPath, path.relative(appFolderPath, file)));
+			files = files.map(file => this.$projectFilesProvider.mapFilePath(file, platformData.normalizedPlatformName, projectData));
 		} else {
 			files = this.$projectFilesManager.getProjectFiles(platformsAppFolderPath);
 		}

test/services/playground/preview-app-livesync-service.ts

@@ -148,7 +148,8 @@ function createTestInjector(options?: {
 				onDeviceFileName: path.basename(filePath),
 				shouldIncludeFile: true
 			};
-		}
+		},
+		mapFilePath: (filePath: string) => path.join(path.join(platformsDirPath, "app"), path.relative(path.join(projectDirPath, "app"), filePath))
 	});
 	injector.register("hooksService", {
 		executeBeforeHooks: (name: string, args: any) => {