more correct emulation of parameter tokens for \index

lib/LaTeXML/Package/LaTeX.pool.ltxml

@@ -4421,15 +4421,7 @@ sub process_index_phrases {
   my @tokens    = $phrases->unlist;
   # check we have a well-formed argument
   return unless @tokens;
-  my $group_level = 0;
-  for my $t (@tokens) {
-    my $cc = $t->getCatcode;
-    if    ($cc == CC_BEGIN) { $group_level++; }
-    elsif ($cc == CC_END) {
-      $group_level--;
-      # discard if unbalanced close group;
-      last if ($group_level < 0); } }
-  if ($group_level != 0) {    # if a group is still open by the end, ill-formed, discard;
+  if (!$phrases->isBalanced) {    # if ill-formed, discard;
     Warn("malformed", "indexentry", $gullet,
       'index entry has unbalanced groups, discarding: "' . ToString($phrases) . '"');
     return; }
@@ -4480,28 +4472,21 @@ DefParameterType('SanitizedVerbatim', sub {
     # chars switched to CC_OTHER by \@sanitize: ' ', '\\', '$', '&', '#', '^', '_', '%', '~'
     # some of those are already in state's "SPECIALS", so only adding the rest:
     StartSemiverbatim(' ', '\\', '%');
-    my $arg = $gullet->readBalanced(1);
+    my $arg = $gullet->readBalanced();
     EndSemiverbatim();
-    # now that we have the semiverbatim tokens, retokenize with the standard catcode scheme,
+    # now that we have the semiverbatim tokens, retokenize.
     # this may seem like wasted work, but it avoids very unfortunate error propagation in cases
     # where the \index argument was malformed for one reason or another.
     #
     # the strangeness comes from the original TeX workflow requiring multiple conversion calls,
     # alongside a call to the `makeidx` binary, which we don't do in latexml. This parameter type
     # emulates one important aspect implied by those steps.
-    $arg = Tokenize(ToString($arg));
+    $arg = TokenizeInternal(UnTeX($arg));
     return $arg; },
-  beforeDigest => sub {
-    $_[0]->bgroup;
-    MergeFont(family => 'typewriter'); },
-  afterDigest => sub {
-    $_[0]->egroup; },
   reversion => sub { (T_BEGIN, Revert($_[0]), T_END); });
 
 # real-world LaTeX \index
 DefMacro('\index SanitizedVerbatim', \&process_index_phrases);
-# simple \index for internal use in bindings with pre-sanitized arguments
-DefMacro('\lx@simple@index Plain', \&process_index_phrases);
 
 Tag('ltx:indexphrase',    afterClose => \&addIndexPhraseKey);
 Tag('ltx:glossaryphrase', afterClose => \&addIndexPhraseKey);

lib/LaTeXML/Package/listings.sty.ltxml

@@ -1019,9 +1019,7 @@ DefKeyVal('LST', 'indexstyle', '');
 DefMacro('\lst@@indexstyle [Number] Until:\end', sub {
     lstSetClassStyle(lstClassName('index', $_[1]), $_[2]); });
 
-# use the simple plain-argument index,
-# otherwise we need to double-check any relevant Semiverbatim cases
-DefMacro('\lstindexmacro{}', '\lx@simple@index{{\ttfamily #1}}');
+DefMacro('\lstindexmacro{}', '\index{{\ttfamily #1}}');
 
 #======================================================================
 # 4.13 Column alignment