extensions/typescript-language-features/src/languageFeatures/completions.ts/MyCompletionItem/getDocumentation
class MyCompletionItem:	private getDocumentation(
		client: ITypeScriptServiceClient,
		detail: Proto.CompletionEntryDetails,
		item: MyCompletionItem
	): vscode.MarkdownString | undefined {
		const documentation = new vscode.MarkdownString();
		if (detail.source) {
			const importPath = `'${Previewer.plainWithLinks(detail.source, client)}'`;
			const autoImportLabel = localize('autoImportLabel', 'Auto import from {0}', importPath);
			item.detail = `${autoImportLabel}\n${item.detail}`;
		}
		Previewer.addMarkdownDocumentation(documentation, detail.documentation, detail.tags, client);

		return documentation.value.length ? documentation : undefined;
	}