Add "Checkout Pull Request" command to chat session context menu (#7669)

* Initial plan

* Initial exploration of chat session context menu structure

Co-authored-by: rebornix <876920+rebornix@users.noreply.github.com>

* Add Checkout Pull Request command to chat session context menu

- Add pr.checkoutChatSessionPullRequest command to package.json
- Add localized title to package.nls.json
- Implement checkoutChatSessionPullRequest function in src/commands.ts
- Register command in src/commands.ts
- Add command to chat/chatSessions context menu positioned above Close Pull Request
- Reuse existing switchToPr functionality for checkout logic

* polish

* fix line feed

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: rebornix <876920+rebornix@users.noreply.github.com>
Co-authored-by: Peng Lyu <penn.lv@gmail.com>

Author: Copilot

package.json

@@ -1752,6 +1752,11 @@
 				"title": "%command.pr.resetCodingAgentPreferences.title%",
 				"category": "%command.pull.request.category%"
 			},
+			{
+				"command": "pr.checkoutChatSessionPullRequest",
+				"title": "%command.pr.checkoutChatSessionPullRequest.title%",
+				"category": "%command.pull.request.category%"
+			},
 			{
 				"command": "pr.closeChatSessionPullRequest",
 				"title": "%command.pr.closeChatSessionPullRequest.title%",
@@ -3418,6 +3423,11 @@
 					"when": "chatSessionType == copilot-swe-agent",
 					"group": "inline"
 				},
+				{
+					"command": "pr.checkoutChatSessionPullRequest",
+					"when": "chatSessionType == copilot-swe-agent",
+					"group": "context"
+				},
 				{
 					"command": "pr.closeChatSessionPullRequest",
 					"when": "chatSessionType == copilot-swe-agent",

package.nls.json

@@ -321,6 +321,7 @@
 	"command.notifications.configureNotificationsViewlet.title": "Configure...",
 	"command.notification.chatSummarizeNotification.title": "Summarize With Copilot",
 	"command.codingAgent.openSessionLog.title": "Open Coding Agent Session Log",
+	"command.pr.checkoutChatSessionPullRequest.title": "Checkout Pull Request",
 	"command.pr.closeChatSessionPullRequest.title": "Close Pull Request",
 	"command.pr.preferredCodingAgentGitHubRemote.title": "Set Preferred GitHub Remote for Coding Agent Sessions",
 	"command.pr.resetCodingAgentPreferences.title": "Reset Coding Agent Workspace Preferences",

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

@@ -164,18 +164,18 @@ declare module 'vscode' {
 	/**
 	 * A specialized progress part for displaying thinking/reasoning steps.
 	 */
-	export class ChatResponseThinkingProgressPart extends ChatResponseProgressPart {
-		value: string;
+	export class ChatResponseThinkingProgressPart {
+		value: string | string[];
 		id?: string;
-		metadata?: string;
+		metadata?: { readonly [key: string]: any };
 		task?: (progress: Progress<LanguageModelThinkingPart>) => Thenable<string | void>;
 
 		/**
 		 * Creates a new thinking progress part.
 		 * @param value An initial progress message
 		 * @param task A task that will emit thinking parts during its execution
 		 */
-		constructor(value: string, id?: string, metadata?: string, task?: (progress: Progress<LanguageModelThinkingPart>) => Thenable<string | void>);
+		constructor(value: string | string[], id?: string, metadata?: { readonly [key: string]: any }, task?: (progress: Progress<LanguageModelThinkingPart>) => Thenable<string | void>);
 	}
 
 	export class ChatResponseReferencePart2 {
@@ -328,18 +328,18 @@ declare module 'vscode' {
 	}
 
 	export type ThinkingDelta = {
-		text?: string;
+		text?: string | string[];
 		id: string;
-		metadata?: string;
+		metadata?: { readonly [key: string]: any };
 	} | {
-		text?: string;
+		text?: string | string[];
 		id?: string;
-		metadata: string;
+		metadata: { readonly [key: string]: any };
 	} |
 	{
-		text: string;
+		text: string | string[];
 		id?: string;
-		metadata?: string;
+		metadata?: { readonly [key: string]: any };
 	};
 
 	export enum ChatResponseClearToPreviousToolInvocationReason {

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

@@ -183,6 +183,8 @@ declare module 'vscode' {
 		isQuotaExceeded?: boolean;
 
 		level?: ChatErrorLevel;
+
+		code?: string;
 	}
 
 	export namespace chat {

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

@@ -42,7 +42,7 @@ declare module 'vscode' {
 		 * A string or heterogeneous array of things that a message can contain as content. Some parts may be message-type
 		 * specific for some models.
 		 */
-		content: Array<LanguageModelTextPart | LanguageModelToolResultPart2 | LanguageModelToolCallPart | LanguageModelDataPart>;
+		content: Array<LanguageModelTextPart | LanguageModelToolResultPart2 | LanguageModelToolCallPart | LanguageModelDataPart | LanguageModelThinkingPart>;
 
 		/**
 		 * The optional name of a user for this message.
@@ -56,7 +56,7 @@ declare module 'vscode' {
 		 * @param content The content of the message.
 		 * @param name The optional name of a user for the message.
 		 */
-		constructor(role: LanguageModelChatMessageRole, content: string | Array<LanguageModelTextPart | LanguageModelToolResultPart2 | LanguageModelToolCallPart | LanguageModelDataPart>, name?: string);
+		constructor(role: LanguageModelChatMessageRole, content: string | Array<LanguageModelTextPart | LanguageModelToolResultPart2 | LanguageModelToolCallPart | LanguageModelDataPart | LanguageModelThinkingPart>, name?: string);
 	}
 
 	/**

src/commands.ts

@@ -967,6 +967,22 @@ export function registerCommands(
 		await openDescription(telemetry, issueModel, descriptionNode, folderManager, revealDescription, !(argument instanceof RepositoryChangesNode), tree.notificationProvider);
 	}
 
+	async function checkoutChatSessionPullRequest(argument: ChatSessionWithPR) {
+		const pr = argument.pullRequest;
+		if (!pr) {
+			Logger.warn(`No pull request found in chat session`, logId);
+			return;
+		}
+
+		const folderManager = reposManager.getManagerForRepository(pr.githubRepository.remote.owner, pr.githubRepository.remote.repositoryName);
+		if (!folderManager) {
+			Logger.warn(`No folder manager found for pull request ${pr.number}`, logId);
+			return vscode.window.showErrorMessage(vscode.l10n.t('Unable to find repository for pull request #{0}', pr.number.toString()));
+		}
+
+		return switchToPr(folderManager, pr, folderManager.repository, false);
+	}
+
 	async function closeChatSessionPullRequest(argument: ChatSessionWithPR) {
 		const pr = argument.pullRequest;
 		if (!pr) {
@@ -988,6 +1004,13 @@ export function registerCommands(
 		// TODO: show a progress icon until the cancelation is finished
 	}
 
+	context.subscriptions.push(
+		vscode.commands.registerCommand(
+			'pr.checkoutChatSessionPullRequest',
+			checkoutChatSessionPullRequest
+		)
+	);
+
 	context.subscriptions.push(
 		vscode.commands.registerCommand(
 			'pr.closeChatSessionPullRequest',