Merge branch 'develop' into doc-cleanup

# Conflicts:
#	base/changes.txt

.github/tl_packages

@@ -22,6 +22,7 @@ hyperref
 oberdiek
 lh
 tex-gyre
+hypdoc
 #
 # special testing for firstaid
 bidi

base/changes.txt

@@ -6,6 +6,12 @@ completeness or accuracy and it contains some references to files that
 are not part of the distribution.
 ================================================================================
 
+2021-11-17  Marcel Krüger  <Marcel.Krueger@latex-project.org>
+
+	* ltluatex.dtx:
+	Classify [hv]pack_quality callbacks as exclusive
+	Never pass true to the engine for LuaTeX list callbacks
+
 2021-11-15  Frank Mittelbach  <Frank.Mittelbach@latex-project.org>
 
 	* build.lua (textfiles):

base/doc/ltnews35.tex

@@ -147,6 +147,19 @@ \subsection{???}
 \section{Code improvements}
 
 
+\subsection{Lua\TeX\ callback improvements}
+
+The Lua\TeX\ callbacks \texttt{hpack\_quality} and \texttt{vpack\_quality} are
+now \texttt{exclusive} and therefore only allow a single handler.
+The previous type \texttt{list} resulted in incorrect parameters when multiple
+handlers were set, therefore this only makes an existing restriction more
+explicit.
+
+Additionally the return value \texttt{true} for \texttt{list} callbacks is now
+handled internally and no longer passed on to the engine. This simplifies the
+handling of these callbacks and makes it easier to provide consistent
+interfaces for user defined \texttt{list} callbacks.
+
 \subsection{???}
 %
 \githubissue{???}

base/ltluatex.dtx

@@ -28,7 +28,7 @@
 \ProvidesFile{ltluatex.dtx}
 %</driver>
 %<*tex>
-[2021/10/15 v1.1v
+[2021/11/17 v1.1w
 %</tex>
 %<plain>  LuaTeX support for plain TeX (core)
 %<*tex>
@@ -1351,6 +1351,8 @@ local callbacktypes = callbacktypes or {
 % \changes{v1.1k}{2019/10/02}{mlist\_to\_hlist is \texttt{exclusive}}
 % \changes{v1.1l}{2020/02/02}{post\_linebreak\_filter is \texttt{reverselist}}
 % \changes{v1.1p}{2020/08/01}{new\_graf is \texttt{exclusive}}
+% \changes{v1.1w}{2021/11/17}{hpack\_quality is \texttt{exclusive}}
+% \changes{v1.1w}{2021/11/17}{vpack\_quality is \texttt{exclusive}}
 %    \begin{macrocode}
   contribute_filter      = simple,
   buildpage_filter       = simple,
@@ -1361,8 +1363,8 @@ local callbacktypes = callbacktypes or {
   post_linebreak_filter  = reverselist,
   hpack_filter           = list,
   vpack_filter           = list,
-  hpack_quality          = list,
-  vpack_quality          = list,
+  hpack_quality          = exclusive,
+  vpack_quality          = exclusive,
   pre_output_filter      = list,
   process_rule           = exclusive,
   hyphenate              = simple,
@@ -1516,11 +1518,11 @@ end
 % Handler for |list| callbacks.
 % \changes{v1.0k}{2015/12/02}{resolve name and i.description (PHG)}
 % \changes{v1.1s}{2020/12/02}{Fix return value of list callbacks}
+% \changes{v1.1w}{2021/11/17}{Never pass on \texttt{true} return values for list callbacks}
 %    \begin{macrocode}
 local function list_handler(name)
   return function(head, ...)
     local ret
-    local alltrue = true
     for _,i in ipairs(callbacklist[name]) do
       ret = i.func(head, ...)
       if ret == false then
@@ -1531,18 +1533,17 @@ local function list_handler(name)
         return false
       end
       if ret ~= true then
-        alltrue = false
         head = ret
       end
     end
-    return alltrue and true or head
+    return head
   end
 end
 %    \end{macrocode}
 % Default for user-defined |list| and |reverselist| callbacks without explicit default.
 %    \begin{macrocode}
-local function list_handler_default()
-  return true
+local function list_handler_default(head)
+return head
 end
 %    \end{macrocode}
 % Handler for |reverselist| callbacks.
@@ -1551,7 +1552,6 @@ end
 local function reverselist_handler(name)
   return function(head, ...)
     local ret
-    local alltrue = true
     local callbacks = callbacklist[name]
     for i = #callbacks, 1, -1 do
       local cb = callbacks[i]
@@ -1564,11 +1564,10 @@ local function reverselist_handler(name)
         return false
       end
       if ret ~= true then
-        alltrue = false
         head = ret
       end
     end
-    return alltrue and true or head
+    return head
   end
 end
 %    \end{macrocode}
@@ -1899,14 +1898,10 @@ callback_register("mlist_to_hlist", function(head, display_type, need_penalties)
   if current == false then
     flush_list(head)
     return nil
-  elseif current == true then
-    current = head
   end
   current = call_callback("mlist_to_hlist", current, display_type, need_penalties)
   local post = call_callback("post_mlist_to_hlist_filter", current, display_type, need_penalties)
-  if post == true then
-    return current
-  elseif post == false then
+  if post == false then
     flush_list(current)
     return nil
   end

base/ltshipout.dtx

@@ -741,8 +741,9 @@
         luatexbase.create_callback('pre_shipout_filter', 'list')
         local~call, getbox, setbox = luatexbase.call_callback, tex.getbox, tex.setbox~
         lua.get_functions_table()[\the \@@_finalize_box:] = function()
-          local~result = call('pre_shipout_filter', getbox(\the \l_shipout_box))
-          if~not (result == true) then~
+          local head = getbox(\the \l_shipout_box)
+          local~result = call('pre_shipout_filter', head)
+          if~not (result == head) then~
             setbox(\the \l_shipout_box, result~or~nil)
           end~
         end

base/testfiles/tlb-ltluatex-001.luatex.tlg

@@ -7,7 +7,7 @@ stack traceback:
 ^^I[C]: in function 'error'
 ^^I./ltluatex.lua:110: in upvalue 'module_error'
 ^^I./ltluatex.lua:117: in upvalue 'luatexbase_error'
-^^I./ltluatex.lua:432: in field 'create_callback'
+^^I./ltluatex.lua:428: in field 'create_callback'
 ^^I[\directlua]:1: in main chunk.
 l. ...}
 The lua interpreter ran into a problem, so the