Add workspace context (#8170)

Part of microsoft/vscode#271104

Author: alexr00

src/@types/vscode.proposed.chatContextProvider.d.ts

@@ -10,28 +10,61 @@ declare module 'vscode' {
 
 	export namespace chat {
 
-		// TODO@alexr00 API:
-		// selector is confusing
-		export function registerChatContextProvider(selector: DocumentSelector, id: string, provider: ChatContextProvider): Disposable;
+		/**
+		 * Register a chat context provider. Chat context can be provided:
+		 * - For a resource. Make sure to pass a selector that matches the resource you want to provide context for.
+		 *   Providers registered without a selector will not be called for resource-based context.
+		 * - Explicitly. These context items are shown as options when the user explicitly attaches context.
+		 *
+		 * To ensure your extension is activated when chat context is requested, make sure to include the `onChatContextProvider:<id>` activation event in your `package.json`.
+		 *
+		 * @param selector Optional document selector to filter which resources the provider is called for. If omitted, the provider will only be called for explicit context requests.
+		 * @param id Unique identifier for the provider.
+		 * @param provider The chat context provider.
+		 */
+		export function registerChatContextProvider(selector: DocumentSelector | undefined, id: string, provider: ChatContextProvider): Disposable;
 
 	}
 
 	export interface ChatContextItem {
+		/**
+		 * Icon for the context item.
+		 */
 		icon: ThemeIcon;
+		/**
+		 * Human readable label for the context item.
+		 */
 		label: string;
+		/**
+		 * An optional description of the context item, e.g. to describe the item to the language model.
+		 */
 		modelDescription?: string;
+		/**
+		 * The value of the context item. Can be omitted when returned from one of the `provide` methods if the provider supports `resolveChatContext`.
+		 */
 		value?: string;
 	}
 
 	export interface ChatContextProvider<T extends ChatContextItem = ChatContextItem> {
 
+		/**
+		 * An optional event that should be fired when the workspace chat context has changed.
+		 */
+		onDidChangeWorkspaceChatContext?: Event<void>;
+
+		/**
+		 * Provide a list of chat context items to be included as workspace context for all chat sessions.
+		 *
+		 * @param token A cancellation token.
+		 */
+		provideWorkspaceChatContext?(token: CancellationToken): ProviderResult<T[]>;
+
 		/**
 		 * Provide a list of chat context items that a user can choose from. These context items are shown as options when the user explicitly attaches context.
 		 * Chat context items can be provided without a `value`, as the `value` can be resolved later using `resolveChatContext`.
 		 * `resolveChatContext` is only called for items that do not have a `value`.
 		 *
-		 * @param options
-		 * @param token
+		 * @param token A cancellation token.
 		 */
 		provideChatContextExplicit?(token: CancellationToken): ProviderResult<T[]>;
 
@@ -40,17 +73,16 @@ declare module 'vscode' {
 		 * Chat context items can be provided without a `value`, as the `value` can be resolved later using `resolveChatContext`.
 		 * `resolveChatContext` is only called for items that do not have a `value`.
 		 *
-		 * @param resource
-		 * @param options
-		 * @param token
+		 * @param options Options include the resource for which to provide context.
+		 * @param token A cancellation token.
 		 */
 		provideChatContextForResource?(options: { resource: Uri }, token: CancellationToken): ProviderResult<T | undefined>;
 
 		/**
 		 * If a chat context item is provided without a `value`, from either of the `provide` methods, this method is called to resolve the `value` for the item.
 		 *
-		 * @param context
-		 * @param token
+		 * @param context The context item to resolve.
+		 * @param token A cancellation token.
 		 */
 		resolveChatContext(context: T, token: CancellationToken): ProviderResult<ChatContextItem>;
 	}

src/extension.ts

@@ -261,8 +261,10 @@ async function init(
 	context.subscriptions.push(issuesFeatures);
 	await issuesFeatures.initialize();
 
-	vscode.chat.registerChatContextProvider({ scheme: 'webview-panel', pattern: '**/webview-PullRequestOverview**' }, 'githubpr', new PullRequestContextProvider(prsTreeModel, reposManager));
+	const pullRequestContextProvider = new PullRequestContextProvider(prsTreeModel, reposManager, git);
+	vscode.chat.registerChatContextProvider({ scheme: 'webview-panel', pattern: '**/webview-PullRequestOverview**' }, 'githubpr', pullRequestContextProvider);
 	vscode.chat.registerChatContextProvider({ scheme: 'webview-panel', pattern: '**/webview-IssueOverview**' }, 'githubissue', new IssueContextProvider(issueStateManager, reposManager));
+	pullRequestContextProvider.initialize();
 
 	const notificationsFeatures = new NotificationsFeatureRegister(credentialStore, reposManager, telemetry, notificationsManager);
 	context.subscriptions.push(notificationsFeatures);

src/lm/pullRequestContextProvider.ts

@@ -4,19 +4,84 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as vscode from 'vscode';
+import { GitApiImpl } from '../api/api1';
+import { Disposable } from '../common/lifecycle';
+import { onceEvent } from '../common/utils';
 import { PullRequestModel } from '../github/pullRequestModel';
 import { PullRequestOverviewPanel } from '../github/pullRequestOverview';
 import { RepositoriesManager } from '../github/repositoriesManager';
 import { PrsTreeModel } from '../view/prsTreeModel';
 
 interface PRChatContextItem extends vscode.ChatContextItem {
-	pr: PullRequestModel;
+	pr?: PullRequestModel;
 }
 
-export class PullRequestContextProvider implements vscode.ChatContextProvider {
+export class PullRequestContextProvider extends Disposable implements vscode.ChatContextProvider {
+	private readonly _onDidChangeWorkspaceChatContext = new vscode.EventEmitter<void>();
+	readonly onDidChangeWorkspaceChatContext = this._onDidChangeWorkspaceChatContext.event;
+
 	constructor(private readonly _prsTreeModel: PrsTreeModel,
-		private readonly _reposManager: RepositoriesManager
-	) { }
+		private readonly _reposManager: RepositoriesManager,
+		private readonly _git: GitApiImpl
+	) {
+		super();
+	}
+
+	/**
+	 * Do this setup in the initialize method so that it can be called after the provider is registered.
+	 */
+	async initialize() {
+		if (this._git.state === 'uninitialized') {
+			await new Promise<void>(resolve => {
+				this._register(onceEvent(this._git.onDidChangeState)(() => resolve()));
+			});
+		}
+		this._reposManager.folderManagers.forEach(folderManager => {
+			this._register(folderManager.onDidChangeActivePullRequest(() => {
+				this._onDidChangeWorkspaceChatContext.fire();
+			}));
+		});
+		this._register(this._reposManager.onDidChangeFolderRepositories(e => {
+			if (!e.added) {
+				return;
+			}
+			this._register(e.added.onDidChangeActivePullRequest(() => {
+				this._onDidChangeWorkspaceChatContext.fire();
+			}));
+			this._onDidChangeWorkspaceChatContext.fire();
+		}));
+		this._register(this._reposManager.onDidChangeAnyGitHubRepository(() => {
+			this._onDidChangeWorkspaceChatContext.fire();
+		}));
+		this._onDidChangeWorkspaceChatContext.fire();
+	}
+
+	async provideWorkspaceChatContext(_token: vscode.CancellationToken): Promise<vscode.ChatContextItem[]> {
+		const modelDescription = this._reposManager.folderManagers.length > 1 ? 'Information about one of the current repositories. You can use this information when you need to calculate diffs or compare changes with the default branch' : 'Information about the current repository. You can use this information when you need to calculate diffs or compare changes with the default branch';
+		const contexts: vscode.ChatContextItem[] = [];
+		for (const folderManager of this._reposManager.folderManagers) {
+			if (folderManager.gitHubRepositories.length === 0) {
+				continue;
+			}
+			const defaults = await folderManager.getPullRequestDefaults();
+
+			let value = `Repository name: ${defaults.repo}
+Owner: ${defaults.owner}
+Current branch: ${folderManager.repository.state.HEAD?.name ?? 'unknown'}
+Default branch: ${defaults.base}`;
+			if (folderManager.activePullRequest) {
+				value = `${value}
+Active pull request (may not be the same as open pull request): #${folderManager.activePullRequest.number} ${folderManager.activePullRequest.html_url}`;
+			}
+			contexts.push({
+				icon: new vscode.ThemeIcon('github-alt'),
+				label: `${defaults.owner}/${defaults.repo}`,
+				modelDescription,
+				value
+			});
+		}
+		return contexts;
+	}
 
 	async provideChatContextForResource(_options: { resource: vscode.Uri }, _token: vscode.CancellationToken): Promise<PRChatContextItem | undefined> {
 		const item = PullRequestOverviewPanel.currentPanel?.getCurrentItem();
@@ -26,6 +91,9 @@ export class PullRequestContextProvider implements vscode.ChatContextProvider {
 	}
 
 	async resolveChatContext(context: PRChatContextItem, _token: vscode.CancellationToken): Promise<vscode.ChatContextItem> {
+		if (!context.pr) {
+			return context;
+		}
 		context.value = await this._resolvedPrValue(context.pr);
 		context.modelDescription = 'All the information about the GitHub pull request the user is viewing, including comments, review threads, and changes.';
 		return context;