extensions/markdown-language-features/src/languageFeatures/documentLinkProvider.ts/MdLinkProvider/provideDocumentLinks
class MdLinkProvider:	public async provideDocumentLinks(
		document: SkinnyTextDocument,
		token: vscode.CancellationToken
	): Promise<vscode.DocumentLink[]> {
		const allLinks = await this.getAllLinks(document);
		if (token.isCancellationRequested) {
			return [];
		}

		const definitionSet = new LinkDefinitionSet(allLinks);
		return coalesce(allLinks
			.map(data => this.toValidDocumentLink(data, definitionSet)));
	}