Test contributing timeline providers from extensions

[eamodio]

Refs: #84297

• anyOS @Tyriar
• anyOS @sbatten

Complexity: 4

---

Testing

Extensions can now contribute timeline providers to show time-series information in a new Timeline view in the Explorer sidebar.

Develop an extension that can contribute a TimelineProvider to provide time-series information given a Uri. Here is an example provider.

Here is the current API declarations:

vscode/src/vs/vscode.proposed.d.ts

Lines 1473 to 1565 in 4f42834

	//#region eamodio - timeline: https://github.com/microsoft/vscode/issues/84297
	export class TimelineItem {
	/**
	* A timestamp (in milliseconds since 1 January 1970 00:00:00) for when the timeline item occurred
	*/
	timestamp: number;
	/**
	* A human-readable string describing the timeline item. When `falsy`, it is derived from [resourceUri](#TreeItem.resourceUri).
	*/
	label: string;
	/**
	* Optional id for the timeline item. See [TreeItem.id](#TreeItem.id) for more details.
	*/
	id?: string;
	/**
	* The icon path or [ThemeIcon](#ThemeIcon) for the timeline item. See [TreeItem.iconPath](#TreeItem.iconPath) for more details.
	*/
	iconPath?: Uri | { light: Uri; dark: Uri } | ThemeIcon;
	/**
	* A human readable string describing less prominent details of the timeline item. See [TreeItem.description](#TreeItem.description) for more details.
	*/
	description?: string;
	/**
	* The tooltip text when you hover over the timeline item.
	*/
	detail?: string;
	/**
	* The [command](#Command) that should be executed when the timeline item is selected.
	*/
	command?: Command;
	/**
	* Context value of the timeline item. See [TreeItem.contextValue](#TreeItem.contextValue) for more details.
	*/
	contextValue?: string;
	/**
	* @param label A human-readable string describing the timeline item
	* @param timestamp A timestamp (in milliseconds since 1 January 1970 00:00:00) for when the timeline item occurred
	* @param source A human-readable string describing the source of the timeline item
	*/
	constructor(label: string, timestamp: number, source: string);
	}
	export interface TimelineProvider {
	onDidChange?: Event<Uri | undefined>;
	/**
	* An identifier of the source of the timeline items. This can be used for filtering and/or overriding existing sources.
	*/
	source: string;
	/**
	* A human-readable string describing the source of the timeline items. This can be as the display label when filtering by sources.
	*/
	sourceDescription: string;
	replaceable?: boolean;
	/**
	* Provide [timeline items](#TimelineItem) for a [Uri](#Uri).
	*
	* @param uri The uri of the file to provide the timeline for.
	* @param token A cancellation token.
	* @return An array of timeline items or a thenable that resolves to such. The lack of a result
	* can be signaled by returning `undefined`, `null`, or an empty array.
	*/
	provideTimeline(uri: Uri, token: CancellationToken): ProviderResult<TimelineItem[]>;
	}
	export namespace workspace {
	/**
	* Register a timeline provider.
	*
	* Multiple providers can be registered. In that case, providers are asked in
	* parallel and the results are merged. A failing provider (rejected promise or exception) will
	* not cause a failure of the whole operation.
	*
	* @param selector A selector that defines the documents this provider is applicable to.
	* @param provider A timeline provider.
	* @return A [disposable](#Disposable) that unregisters this provider when being disposed.
	*/
	export function registerTimelineProvider(selector: DocumentSelector, provider: TimelineProvider): Disposable;
	}
	//#endregion

)

• Make sure there is a command contributed to each timeline item for the on click action.
• Try making a provider take a while and make sure the view shows an indication of progress/loading
• Try updating provider data after initial load (using onDidChange) and ensure the view is updated
• For extra points, try setting replaceable to true and then register a replacement provider using the same source -- it should replace the existing one. Also try the same thing without setting replaceable (or set to false) and the second registration should error out.

Notes

• The DocumentSelector as part of the registerTimelineProvider call isn't yet honored
• You cannot (yet) attach context menus to timeline items

[Tyriar]

I can't get the API to work. With the following ext code:

import * as vscode from 'vscode';

const backups: { [uri: string]: string[] } = {};

export function activate(context: vscode.ExtensionContext) {
	console.log('activate');
	context.subscriptions.push(vscode.workspace.onDidSaveTextDocument(d => {
		const uri = d.uri.toString();
		if (backups[uri] === undefined) {
			backups[uri] = [];
		}
		backups[uri].push(d.getText());
		console.log('backed up');
	}));
	const changeEmitter = new vscode.EventEmitter<vscode.Uri | undefined>();
	context.subscriptions.push(vscode.workspace.registerTimelineProvider('*', {
		source: 'my-magical-timeline-provider',
		sourceDescription: 'My magical timeline provider',
		provideTimeline: (uri: vscode.Uri, token: vscode.CancellationToken) => {
			console.log('provide');
			const result: vscode.TimelineItem[] = [
				new (vscode.TimelineItem as any)('rawr', Date.now())
			];
			return result;
		},
		onDidChange: changeEmitter.event
	}));
}

backed up gets logged but not provide:

[Tyriar]

Tried again and still having problems, closing off as I'm blocked. Hopefully the root cause of the problem will surface before the API is stabilized.