Allow extensions to specify custom tree view resoure type

src/vs/vscode.d.ts

@@ -5063,6 +5063,25 @@ declare module 'vscode' {
 		getChildren(element?: T): ProviderResult<T[]>;
 	}
 
+	/**
+	 * A category in a File Icon Theme, either [file](#ThemeIcon.file) or [folder](#ThemeIcon.folder)
+	 */
+	export class ThemeIcon {
+		/**
+		 * Use the File Icon Theme for files
+		 */
+		static readonly File: ThemeIcon;
+
+		/**
+		 * Use the File Icon Theme for files
+		 */
+		static readonly Folder: ThemeIcon;
+
+		readonly id: string;
+
+		private constructor(id: string);
+	}
+
 	export class TreeItem {
 		/**
 		 * A human-readable string describing this item. When `falsy`, it is derived from [resourceUri](#TreeItem.resourceUri).
@@ -5077,15 +5096,17 @@ declare module 'vscode' {
 		id?: string;
 
 		/**
-		 * The icon path for the tree item. When `falsy`, it is derived from [resourceUri](#TreeItem.resourceUri).
+		 * The icon path for the tree item.
+		 * When `falsy` it is derived from [resourceUri](#TreeItem.resourceUri) and the current theme (As a file if the node isn't collapsible or for folders otherwise)
+		 * When a [ThemeIcon](#ThemeIcon) is specified it is derived from [resourceUri](#TreeItem.resourceUri) and the current theme for the specified category.
 		 */
-		iconPath?: string | Uri | { light: string | Uri; dark: string | Uri };
+		iconPath?: string | Uri | { light: string | Uri | ThemeIcon; dark: string | Uri | ThemeIcon } | ThemeIcon;
 
 		/**
 		 * The [uri](#Uri) of the resource representing this item.
 		 *
 		 * Will be used to derive the [label](#TreeItem.label), when it is not provided.
-		 * Will be used to derive the icon from current file icon theme, when [iconPath](#TreeItem.iconPath) is not provided.
+		 * Will be used to derive the icon from current icon theme, when [iconPath](#TreeItem.iconPath) is not provided or is a [ThemeIcon](#ThemeIcon).
 		 */
 		resourceUri?: Uri;
 

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -623,6 +623,7 @@ export function createApiFactory(
 			WorkspaceEdit: extHostTypes.WorkspaceEdit,
 			ProgressLocation: extHostTypes.ProgressLocation,
 			TreeItemCollapsibleState: extHostTypes.TreeItemCollapsibleState,
+			ThemeIcon: extHostTypes.ThemeIcon,
 			TreeItem: extHostTypes.TreeItem,
 			ThemeColor: extHostTypes.ThemeColor,
 			// functions

src/vs/workbench/api/node/extHostTreeViews.ts

@@ -12,10 +12,10 @@ import { debounceEvent } from 'vs/base/common/event';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { Disposable } from 'vs/base/common/lifecycle';
 import { ExtHostTreeViewsShape, MainThreadTreeViewsShape } from './extHost.protocol';
-import { ITreeItem, TreeViewItemHandleArg } from 'vs/workbench/common/views';
+import { ITreeItem, TreeViewItemHandleArg, IThemeIcon } from 'vs/workbench/common/views';
 import { ExtHostCommands, CommandsConverter } from 'vs/workbench/api/node/extHostCommands';
 import { asWinJsPromise } from 'vs/base/common/async';
-import { TreeItemCollapsibleState } from 'vs/workbench/api/node/extHostTypes';
+import { TreeItemCollapsibleState, ThemeIcon } from 'vs/workbench/api/node/extHostTypes';
 import { isUndefinedOrNull } from 'vs/base/common/types';
 
 type TreeItemHandle = string;
@@ -315,27 +315,32 @@ class ExtHostTreeView<T> extends Disposable {
 		throw new Error('This should not be reached');
 	}
 
-	private getLightIconPath(extensionTreeItem: vscode.TreeItem): string {
+	private getLightIconPath(extensionTreeItem: vscode.TreeItem): string | IThemeIcon {
 		if (extensionTreeItem.iconPath) {
-			if (typeof extensionTreeItem.iconPath === 'string' || extensionTreeItem.iconPath instanceof URI) {
+			if (typeof extensionTreeItem.iconPath === 'string'
+				|| extensionTreeItem.iconPath instanceof URI
+				|| extensionTreeItem.iconPath instanceof ThemeIcon) {
 				return this.getIconPath(extensionTreeItem.iconPath);
 			}
 			return this.getIconPath(extensionTreeItem.iconPath['light']);
 		}
 		return void 0;
 	}
 
-	private getDarkIconPath(extensionTreeItem: vscode.TreeItem): string {
+	private getDarkIconPath(extensionTreeItem: vscode.TreeItem): string | IThemeIcon {
 		if (extensionTreeItem.iconPath && extensionTreeItem.iconPath['dark']) {
 			return this.getIconPath(extensionTreeItem.iconPath['dark']);
 		}
 		return void 0;
 	}
 
-	private getIconPath(iconPath: string | URI): string {
+	private getIconPath(iconPath: string | URI | ThemeIcon): string | IThemeIcon {
 		if (iconPath instanceof URI) {
 			return iconPath.toString();
 		}
+		if (iconPath instanceof ThemeIcon) {
+			return { id: iconPath.id };
+		}
 		return URI.file(iconPath).toString();
 	}
 

src/vs/workbench/api/node/extHostTypes.ts

@@ -1544,6 +1544,18 @@ export enum TreeItemCollapsibleState {
 	Expanded = 2
 }
 
+export class ThemeIcon {
+	static readonly File = new ThemeIcon('file');
+
+	static readonly Folder = new ThemeIcon('folder');
+
+	readonly id: string;
+
+	private constructor(id: string) {
+		this.id = id;
+	}
+}
+
 export class ThemeColor {
 	id: string;
 	constructor(id: string) {

src/vs/workbench/browser/parts/views/customView.ts

@@ -13,7 +13,7 @@ import * as DOM from 'vs/base/browser/dom';
 import { $ } from 'vs/base/browser/builder';
 import { LIGHT } from 'vs/platform/theme/common/themeService';
 import { ITree, IDataSource, IRenderer, ContextMenuEvent } from 'vs/base/parts/tree/browser/tree';
-import { TreeItemCollapsibleState, ITreeItem, ITreeViewer, ICustomViewsService, ITreeViewDataProvider, ViewsRegistry, IViewDescriptor, TreeViewItemHandleArg, ICustomViewDescriptor, IViewsViewlet } from 'vs/workbench/common/views';
+import { TreeItemCollapsibleState, ITreeItem, ITreeViewer, ICustomViewsService, ITreeViewDataProvider, ViewsRegistry, IViewDescriptor, TreeViewItemHandleArg, ICustomViewDescriptor, IViewsViewlet, FileThemeIconId, FolderThemeIconId } from 'vs/workbench/common/views';
 import { IWorkbenchThemeService } from 'vs/workbench/services/themes/common/workbenchThemeService';
 import { IExtensionService } from 'vs/workbench/services/extensions/common/extensions';
 import { IProgressService2, ProgressLocation } from 'vs/platform/progress/common/progress';
@@ -447,8 +447,19 @@ class TreeRenderer implements IRenderer {
 		DOM.removeClass(templateData.label, 'custom-view-tree-node-item-label');
 		DOM.removeClass(templateData.resourceLabel.element, 'custom-view-tree-node-item-resourceLabel');
 
-		if (resource && !icon) {
-			templateData.resourceLabel.setLabel({ name: label, resource }, { fileKind: node.collapsibleState === TreeItemCollapsibleState.Collapsed || node.collapsibleState === TreeItemCollapsibleState.Expanded ? FileKind.FOLDER : FileKind.FILE, title: node.tooltip });
+		if (resource && (typeof icon !== 'string')) {
+			let fileKind = node.collapsibleState === TreeItemCollapsibleState.Collapsed || node.collapsibleState === TreeItemCollapsibleState.Expanded ? FileKind.FOLDER : FileKind.FILE;
+			if (icon && icon.id) {
+				switch (icon.id) {
+					case FileThemeIconId:
+						fileKind = FileKind.FILE;
+						break;
+					case FolderThemeIconId:
+						fileKind = FileKind.FOLDER;
+						break;
+				}
+			}
+			templateData.resourceLabel.setLabel({ name: label, resource }, { fileKind, title: node.tooltip });
 			DOM.addClass(templateData.resourceLabel.element, 'custom-view-tree-node-item-resourceLabel');
 		} else {
 			templateData.label.textContent = label;
@@ -493,7 +504,7 @@ class TreeItemIcon extends Disposable {
 			const fileIconTheme = this.themeService.getFileIconTheme();
 			const contributedIcon = this.themeService.getTheme().type === LIGHT ? this._treeItem.icon : this._treeItem.iconDark;
 
-			const hasContributedIcon = !!contributedIcon;
+			const hasContributedIcon = typeof contributedIcon === 'string';
 			const hasChildren = this._treeItem.collapsibleState !== TreeItemCollapsibleState.None;
 			const hasResource = !!this._treeItem.resourceUri;
 			const isFolder = hasResource && hasChildren;

src/vs/workbench/common/views.ts

@@ -202,6 +202,13 @@ export enum TreeItemCollapsibleState {
 	Expanded = 2
 }
 
+export const FileThemeIconId = 'file';
+export const FolderThemeIconId = 'folder';
+
+export interface IThemeIcon {
+	readonly id: string;
+}
+
 export interface ITreeItem {
 
 	handle: string;
@@ -212,9 +219,9 @@ export interface ITreeItem {
 
 	label?: string;
 
-	icon?: string;
+	icon?: string | IThemeIcon;
 
-	iconDark?: string;
+	iconDark?: string | IThemeIcon;
 
 	resourceUri?: UriComponents;