src/vs/workbench/api/common/extHostFileSystem.ts/FsLinkProvider/provideDocumentLinks
class FsLinkProvider:	provideDocumentLinks(document: vscode.TextDocument): vscode.ProviderResult<vscode.DocumentLink[]> {
		this._initStateMachine();

		const result: vscode.DocumentLink[] = [];
		const links = LinkComputer.computeLinks({
			getLineContent(lineNumber: number): string {
				return document.lineAt(lineNumber - 1).text;
			},
			getLineCount(): number {
				return document.lineCount;
			}
		}, this._stateMachine);

		for (const link of links) {
			const docLink = typeConverter.DocumentLink.to(link);
			if (docLink.target) {
				result.push(docLink);
			}
		}
		return result;
	}