From 7e000a0db1c04b076ba5b935801d7ca9db760015 Mon Sep 17 00:00:00 2001
From: Ulrike Fischer <fischer@troubleshooting-tex.de>
Date: Tue, 28 Jan 2025 00:20:06 +0100
Subject: [PATCH] use sockets for math phantoms

---
 luamml-patches-kernel.sty | 52 ++++++++++++++++++-----------------
 luamml.dtx                | 57 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+), 24 deletions(-)

diff --git a/luamml-patches-kernel.sty b/luamml-patches-kernel.sty
index 38eb28b..304cf26 100644
--- a/luamml-patches-kernel.sty
+++ b/luamml-patches-kernel.sty
@@ -22,30 +22,34 @@
   }
 }
 
-\cs_set:Npn \mathph@nt #1 #2 {
-  \setbox \z@ = \hbox {
-    $
-    \m@th
-    #1
-    {#2}
-    \luamml_save:nNn {mathphant} #1 {mphantom}
-    $
-  }
-  \luamml_annotate:nen {1} {
-    nucleus = true,
-    core = {[0] = 'mpadded',
-      \ifh@\else
-        width = 0,
-      \fi
-      \ifv@\else
-        height = 0, depth = 0,
-      \fi
-      consume_label'mathphant',
-    }
-  } {
-    \finph@nt
-  }
-}
+\IfPackageAtLeastTF{latex-lab-testphase-text}{2025-01-27}
+ {}
+ {
+   \cs_set:Npn \mathph@nt #1 #2 {
+     \setbox \z@ = \hbox {
+       $
+       \m@th
+       #1
+       {#2}
+       \luamml_save:nNn {mathphant} #1 {mphantom}
+       $
+     }
+     \luamml_annotate:nen {1} {
+       nucleus = true,
+       core = {[0] = 'mpadded',
+         \ifh@\else
+           width = 0,
+         \fi
+         \ifv@\else
+           height = 0, depth = 0,
+         \fi
+         consume_label'mathphant',
+       }
+     } {
+       \finph@nt
+     }
+   }
+ }
 
 \@ifpackageloaded {unicode-math} {} {
   \cs_new:Npn \__luamml_kernel_define_character:Nnn #1#2#3 {
diff --git a/luamml.dtx b/luamml.dtx
index c492c10..2494975 100644
--- a/luamml.dtx
+++ b/luamml.dtx
@@ -527,6 +527,25 @@
 % In various places luamml has to add code to kernel commands. This is done through
 % sockets which are predeclared in lttagging.
 %
+% \subsubsection{Save socket}
+% This socket is a wrapper around the \cs{luamml_save:nNn} command
+% It should provided until 2025-06-01
+%    \begin{macrocode}
+\str_if_exist:cF { l__socket_tagsupport/math/luamml/save_plug_str }
+ {
+   \NewSocket{tagsupport/math/luamml/save}{1}
+   \AssignSocketPlug{tagsupport/math/luamml/save}{noop}
+ }  
+%    \end{macrocode}
+%
+%    \begin{macrocode}
+\NewSocketPlug{tagsupport/math/luamml/save}{luamml}
+ {
+   \luamml_save:nNn #1
+ }
+\AssignSocketPlug{tagsupport/math/luamml/save}{luamml}
+%    \end{macrocode}
+%  
 % \subsubsection{amsmath alignments}
 %
 % This socket finalize the \texttt{mtable} in alignments like align or gather.
@@ -610,6 +629,44 @@
 \AssignSocketPlug{tagsupport/math/luamml/artifact}{default}
 %</luatex>
 %    \end{macrocode}
+%
+% \subsubsection{Math phantom socket}
+% This socket is used around \cs{finph@nt}. 
+% It should provided until 2025-06-01
+%    \begin{macrocode}
+\str_if_exist:cF { l__socket_tagsupport/math/luamml/finph@nt_plug_str }
+ {
+   \NewSocket{tagsupport/math/luamml/finph@nt}{2}
+   \NewSocketPlug{tagsupport/math/luamml/finph@nt}{default}{#2}
+   \AssignSocketPlug{tagsupport/math/luamml/finph@nt}{default}
+ }  
+%    \end{macrocode}
+%
+%    \begin{macrocode}
+%<*luatex>
+\NewSocketPlug{tagsupport/math/luamml/finph@nt}{luamml}
+ {
+   \luamml_annotate:nen {1} 
+    {
+     nucleus = true,
+     core = 
+       {
+        [0] = 'mpadded',
+        \ifh@\else
+         width = 0,
+        \fi
+        \ifv@\else
+         height = 0, depth = 0,
+        \fi
+        consume_label'mathphant',
+      }
+    }
+    { #2 }  
+ }
+\AssignSocketPlug{tagsupport/math/luamml/finph@nt}{luamml}
+%</luatex>
+%    \end{macrocode} 
+% 
 % \subsection{Patching}
 % For some packages, we ship with patches to make them more compatible and to
 % demonstrate how other code can be patched to work with \texttt{luamml}.