allow workspaces with 0 folders (#34622)

src/vs/platform/workspaces/electron-main/workspacesMainService.ts

@@ -103,13 +103,13 @@ export class WorkspacesMainService implements IWorkspacesMainService {
 			throw new Error(`${path} cannot be parsed as JSON file (${error}).`);
 		}
 
-		// Filter out folders which do not have a path set
+		// Filter out folders which do not have a path or uri set
 		if (Array.isArray(storedWorkspace.folders)) {
 			storedWorkspace.folders = storedWorkspace.folders.filter(folder => isStoredWorkspaceFolder(folder));
 		}
 
 		// Validate
-		if (!Array.isArray(storedWorkspace.folders) || storedWorkspace.folders.length === 0) {
+		if (!Array.isArray(storedWorkspace.folders)) {
 			throw new Error(`${path} looks like an invalid workspace file.`);
 		}
 

src/vs/workbench/parts/files/browser/fileActions.contribution.ts

@@ -92,14 +92,13 @@ class FilesViewerActionContributor extends ActionBarContributor {
 		}
 
 		if (stat.isRoot && this.environmentService.appQuality !== 'stable') {
-			let action: Action = this.instantiationService.createInstance(AddRootFolderAction, AddRootFolderAction.ID, AddRootFolderAction.LABEL);
-			action.order = 52;
-			actions.push(action);
-			if (this.contextService.getWorkspace().folders.length > 1) {
-				action = this.instantiationService.createInstance(RemoveRootFolderAction, stat.resource, RemoveRootFolderAction.ID, RemoveRootFolderAction.LABEL);
-				action.order = 53;
-				actions.push(action);
-			}
+			const addRootFolderAction: Action = this.instantiationService.createInstance(AddRootFolderAction, AddRootFolderAction.ID, AddRootFolderAction.LABEL);
+			addRootFolderAction.order = 52;
+			actions.push(addRootFolderAction);
+
+			const removeRootFolderAction = this.instantiationService.createInstance(RemoveRootFolderAction, stat.resource, RemoveRootFolderAction.ID, RemoveRootFolderAction.LABEL);
+			removeRootFolderAction.order = 53;
+			actions.push(removeRootFolderAction);
 			actions.push(new Separator(null, 54));
 		}
 

src/vs/workbench/services/configuration/node/configuration.ts

@@ -211,9 +211,9 @@ contributionRegistry.registerSchema('vscode://schemas/workspaceConfig', {
 	required: ['folders'],
 	properties: {
 		'folders': {
-			minItems: 1,
+			minItems: 0,
 			uniqueItems: true,
-			description: nls.localize('workspaceConfig.folders.description', "List of folders to be loaded in the workspace. Must be a file path. e.g. `/root/folderA` or `./folderA` for a relative path that will be resolved against the location of the workspace file."),
+			description: nls.localize('workspaceConfig.folders.description', "List of folders to be loaded in the workspace."),
 			items: {
 				type: 'object',
 				default: { path: '' },
@@ -407,9 +407,6 @@ export class WorkspaceService extends Disposable implements IWorkspaceConfigurat
 			.then(() => {
 				const workspaceConfigurationModel = this.workspaceConfiguration.workspaceConfigurationModel;
 				const workspaceFolders = toWorkspaceFolders(workspaceConfigurationModel.folders, URI.file(paths.dirname(workspaceConfigPath.fsPath)));
-				if (!workspaceFolders.length) {
-					return TPromise.wrapError<Workspace>(new Error('Invalid workspace configuraton file ' + workspaceConfigPath));
-				}
 				const workspaceId = workspaceIdentifier.id;
 				const workspaceName = getWorkspaceLabel({ id: workspaceId, configPath: workspaceConfigPath.fsPath }, this.environmentService);
 				return new Workspace(workspaceId, workspaceName, workspaceFolders, workspaceConfigPath);