Support generating PR descriptions based on a template

src/extension/prompt/node/githubPullRequestTitleAndDescriptionGenerator.ts

@@ -73,16 +73,17 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 		return patches;
 	}
 
-	async provideTitleAndDescription(context: { commitMessages: string[]; patches: string[] | { patch: string; fileUri: string; previousFileUri?: string }[]; issues?: { reference: string; content: string }[] }, token: CancellationToken): Promise<{ title: string; description?: string } | undefined> {
+	async provideTitleAndDescription(context: { commitMessages: string[]; patches: string[] | { patch: string; fileUri: string; previousFileUri?: string }[]; issues?: { reference: string; content: string }[]; template?: string }, token: CancellationToken): Promise<{ title: string; description?: string } | undefined> {
 		const commitMessages: string[] = context.commitMessages;
 		const allPatches: { patch: string; fileUri?: string; previousFileUri?: string }[] = isStringArray(context.patches) ? context.patches.map(patch => ({ patch })) : context.patches;
 		const patches = await this.excludePatches(allPatches);
 		const issues: { reference: string; content: string }[] | undefined = context.issues;
+		const template: string | undefined = context.template;
 
 		const endpoint = await this.endpointProvider.getChatEndpoint('gpt-4o-mini');
 		const charLimit = Math.floor((endpoint.modelMaxPromptTokens * 4) / 3);
 
-		const prompt = await this.createPRTitleAndDescriptionPrompt(commitMessages, patches, issues, charLimit);
+		const prompt = await this.createPRTitleAndDescriptionPrompt(commitMessages, patches, issues, template, charLimit);
 		const fetchResult = await endpoint
 			.makeChatRequest(
 				'githubPullRequestTitleAndDescriptionGenerator',
@@ -105,10 +106,10 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 			return undefined;
 		}
 
-		return GitHubPullRequestTitleAndDescriptionGenerator.parseFetchResult(fetchResult.value);
+		return GitHubPullRequestTitleAndDescriptionGenerator.parseFetchResult(fetchResult.value, !!template);
 	}
 
-	public static parseFetchResult(value: string, retry: boolean = true): { title: string; description?: string } | undefined {
+	public static parseFetchResult(value: string, hasTemplate: boolean = false, retry: boolean = true): { title: string; description?: string } | undefined {
 		value = value.trim();
 		let workingValue = value;
 		let delimiter = '+++';
@@ -130,8 +131,13 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 			// If there's only one line, split on newlines as the model has left out some +++ delimiters
 			splitOnLines = splitOnPlus[0].split('\n');
 		} else if (splitOnPlus.length > 1) {
-			const descriptionLines = splitOnPlus.slice(1).map(line => line.split('\n')).flat().filter(s => s.trim().length > 0);
-			splitOnLines = [splitOnPlus[0], ...descriptionLines];
+			if (hasTemplate) {
+				// When using a template, keep description whitespace as-is.
+				splitOnLines = splitOnPlus;
+			} else {
+				const descriptionLines = splitOnPlus.slice(1).map(line => line.split('\n')).flat().filter(s => s.trim().length > 0);
+				splitOnLines = [splitOnPlus[0], ...descriptionLines];
+			}
 		} else {
 			return undefined;
 		}
@@ -141,7 +147,7 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 		if (splitOnLines.length === 1) {
 			title = splitOnLines[0].trim();
 			if (retry && value.includes('\n') && (value.split(delimiter).length === 3)) {
-				return this.parseFetchResult(value + delimiter, false);
+				return this.parseFetchResult(value + delimiter, hasTemplate, false);
 			}
 		} else if (splitOnLines.length > 1) {
 			title = splitOnLines[0].trim();
@@ -159,14 +165,14 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 		if (title) {
 			title = title.replace(/Title\:\s/, '').trim();
 			title = title.replace(/^\"(?<title>.+)\"$/, (_match, title) => title);
-			if (description) {
+			if (description && !hasTemplate) {
 				description = description.replace(/Description\:\s/, '').trim();
 			}
 			return { title, description };
 		}
 	}
 
-	private async createPRTitleAndDescriptionPrompt(commitMessages: string[], patches: string[], issues: { reference: string; content: string }[] | undefined, charLimit: number): Promise<RenderPromptResult> {
+	private async createPRTitleAndDescriptionPrompt(commitMessages: string[], patches: string[], issues: { reference: string; content: string }[] | undefined, template: string | undefined, charLimit: number): Promise<RenderPromptResult> {
 		// Reserve 20% of the character limit for the safety rules and instructions
 		const availableChars = charLimit - Math.floor(charLimit * 0.2);
 
@@ -184,7 +190,7 @@ export class GitHubPullRequestTitleAndDescriptionGenerator implements TitleAndDe
 		}
 
 		const endpoint = await this.endpointProvider.getChatEndpoint('gpt-4o-mini');
-		const promptRenderer = PromptRenderer.create(this.instantiationService, endpoint, GitHubPullRequestPrompt, { commitMessages, issues, patches });
+		const promptRenderer = PromptRenderer.create(this.instantiationService, endpoint, GitHubPullRequestPrompt, { commitMessages, issues, patches, template });
 		return promptRenderer.render(undefined, undefined);
 	}
 }

src/extension/prompts/node/github/pullRequestDescriptionPrompt.tsx

@@ -11,6 +11,7 @@ interface GitHubPullRequestPromptProps extends BasePromptElementProps {
 	commitMessages: string[];
 	patches: string[];
 	issues: { reference: string; content: string }[] | undefined;
+	template: string | undefined;
 }
 
 interface GitHubPullRequestIdentityProps extends BasePromptElementProps {
@@ -76,6 +77,7 @@ class GitHubPullRequestSystemRules extends PromptElement<GitHubPullRequestIdenti
 				To compose the description, read through each commit and patch and tersly describe the intent of the changes, not the changes themselves. Do not list commits, files or patches. Do not make up an issue reference if the pull request isn't fixing an issue.<br />
 				If the pull request is fixing an issue, consider how the commits relate to the issue and include that in the description.<br />
 				Avoid saying "this PR" or similar. Avoid passive voice.<br />
+				If a template is specified, the description must match the template, filling in any required fields.<br />
 				The title and description of a pull request should be markdown and start with +++ and end with +++.<br />
 				<GitHubPullRequestSystemExamples issues={this.props.issues} />
 			</>
@@ -86,6 +88,7 @@ class GitHubPullRequestSystemRules extends PromptElement<GitHubPullRequestIdenti
 interface GitHubPullRequestUserMessageProps extends BasePromptElementProps {
 	commitMessages: string[];
 	patches: string[];
+	template: string | undefined;
 }
 
 class GitHubPullRequestUserMessage extends PromptElement<GitHubPullRequestUserMessageProps> {
@@ -98,6 +101,14 @@ class GitHubPullRequestUserMessage extends PromptElement<GitHubPullRequestUserMe
 				{formattedCommitMessages}<br />
 				Below is a list of git patches that contain the file changes for all the files that will be included in the pull request:<br />
 				{formattedPatches}<br />
+				{this.props.template && (
+					<>
+						The pull request description should match the following template:<br />
+						```<br />
+						{this.props.template}<br />
+						```<br />
+					</>
+				)}
 				Based on the git patches and on the git commit messages above, the title and description of the pull request should be:<br />
 			</>
 		);
@@ -113,7 +124,7 @@ export class GitHubPullRequestPrompt extends PromptElement<GitHubPullRequestProm
 					<SafetyRules />
 				</SystemMessage>
 				<UserMessage>
-					<GitHubPullRequestUserMessage commitMessages={this.props.commitMessages} patches={this.props.patches} />
+					<GitHubPullRequestUserMessage commitMessages={this.props.commitMessages} patches={this.props.patches} template={this.props.template} />
 					<Tag priority={750} name='custom-instructions'>
 						<CustomInstructions
 							chatVariables={undefined}

test/outcome/pr-title-and-description-context.json

@@ -2,7 +2,7 @@
 	{
 		"name": "PR Title and Description [context] - Multiple commits without issue information",
 		"requests": [
-			"8428a33bed887a6b29356a7e240e42a90fcea91744ec3477395eb5d23dbed752"
+			"c661b19df36a5e6b216162071bf3a758898a0365e5d29c86deb4c01d5927a4ca"
 		]
 	}
 ]