message: Double check arg types of sections
diff: @@ -178,15 +178,28 @@ export class SectionNodeProvider implements vscode.TreeDataProvider<Section> {
  if (latexParser.isCommand(node)) {
  if (commands.secs.includes(node.name.replace(/\*$/, ''))) {
  // \section{Title}
  + if (node.args.length > 0) {
  + // Avoid \section alone
  + let captionArg: latexParser.Group | undefined
  + if (node.args.length === 1 && latexParser.isGroup(node.args[0])) {
  + captionArg = node.args[0]
  + } else if (node.args.length === 2 && latexParser.isOptionalArg(node.args[0]) && latexParser.isGroup(node.args[1])) {
  + captionArg = node.args[1]
  + } else {
  + captionArg = node.args.find(latexParser.isGroup)
  + }
  + if (captionArg) {
  sections.push(new Section(
  node.name.endsWith('*') ? SectionKind.NoNumberSection : SectionKind.Section,
  - this.captionify(node.args[node.args.length - 1]),
  + this.captionify(captionArg),
  vscode.TreeItemCollapsibleState.Expanded,
  depths[node.name.replace(/\*$/, '')],
  node.location.start.line - 1,
  node.location.end.line - 1,
  file
  ))
  + }
  + }
  } else if (commands.cmds.includes(node.name.replace(/\*$/, ''))) {
  // \notlabel{Show}{ShowAlso}
  const caption = node.args.map(arg => {
  