lua-widow-control (15feb22)

git-svn-id: svn://tug.org/texlive/trunk@62050 c570f23f-e606-0410-a88d-b1316a301751

4 files changed, 57 insertions, 23 deletions

diff --git a/Master/texmf-dist/tex/context/third/lua-widow-control/t-lua-widow-control.mkxl b/Master/texmf-dist/tex/context/third/lua-widow-control/t-lua-widow-control.mkxl
index 436eb880cb3..b38d6eda018 100644
--- a/Master/texmf-dist/tex/context/third/lua-widow-control/t-lua-widow-control.mkxl
+++ b/Master/texmf-dist/tex/context/third/lua-widow-control/t-lua-widow-control.mkxl
@@ -1,10 +1,10 @@
 %D \module
 %D   [     file=t-lua-widow-control,
-%D      version=1.1.4, %%version
+%D      version=1.1.5, %%version
 %D        title=lua-widow-control,
 %D     subtitle=\ConTeXt module for lua-widow-control,
 %D       author=Max Chernoff,
-%D         date=2022-02-04, %%date
+%D         date=2022-02-15, %%date
 %D    copyright=Max Chernoff,
 %D      license=MPL-2.0+,
 %D          url=https://github.com/gucci-on-fleek/lua-widow-control]
diff --git a/Master/texmf-dist/tex/lualatex/lua-widow-control/lua-widow-control.sty b/Master/texmf-dist/tex/lualatex/lua-widow-control/lua-widow-control.sty
index 81dd969d8da..1be00709bc8 100644
--- a/Master/texmf-dist/tex/lualatex/lua-widow-control/lua-widow-control.sty
+++ b/Master/texmf-dist/tex/lualatex/lua-widow-control/lua-widow-control.sty
@@ -5,7 +5,14 @@
 
 \NeedsTeXFormat{LaTeX2e}[2015/01/01] % Formats built after 2015 include \LuaTeX{}Base
 \ProvidesPackage{lua-widow-control}%
-    [2022/02/04 v1.1.4] %%version %%date
+    [2022/02/15 v1.1.5] %%version %%date
+
+\ifdefined\directlua\else
+    \PackageError{lua-widow-control}{%
+        LuaTeX is required for this package.\MessageBreak
+        Make sure to compile with `lualatex'%
+    }{}
+\fi
 
 \clubpenalty=1
 \widowpenalty=1
@@ -22,7 +29,15 @@
 % Here, we enable font expansion/contraction. It isn't strictly necessary for
 % \lwc/'s functionality; however, it is required for the
 % lengthened paragraphs to not have terrible spacing. 
-\RequirePackage[final]{microtype}
+\RequirePackage{etoolbox}
+\AtEndPreamble{
+    \@ifpackageloaded{microtype}{}{ % Only load if not already loaded
+        \RequirePackage[
+            final,
+            activate={true,nocompatibility}
+        ]{microtype}
+    }
+}
 
 % Define \TeX{} wrappers for Lua functions
 \newcommand{\lwcenable}{\directlua{lwc.enable_callbacks()}}
@@ -34,8 +49,6 @@
 
 % Expansion of some parts of the document, such as section headings, is quite
 % undesirable, so we'll disable \lwc/ for certain commands.
-\RequirePackage{etoolbox}
-
 \newcommand{\lwc@patch@warning}[1]{\PackageWarning{lua-widow-control}{%
     Patching the \protect#1 command failed%
 }}
diff --git a/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.lua b/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.lua
index 9a8b2efa781..9304bf9a4d1 100644
--- a/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.lua
+++ b/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.lua
@@ -59,14 +59,16 @@ assert(lwc.context or luatexbase, [[
   ]]
 if lwc.context then
     lwc.warning = logs.reporter("module", lwc.name)
+    lwc.info = logs.reporter("module", lwc.name)
     lwc.attribute = attributes.public(lwc.name)
     lwc.contrib_head = 'contributehead' -- For \LuaMetaTeX{}
     lwc.stretch_order = "stretchorder"
+    lwc.pagenum = function () return tex.count["realpageno"] end
 elseif lwc.plain or lwc.latex then
     luatexbase.provides_module {
         name = lwc.name,
-        date = "2022/02/04", --%%date
-        version = "1.1.4", --%%version
+        date = "2022/02/15", --%%date
+        version = "1.1.5", --%%version
         description = [[
 
     This module provides a LuaTeX-based solution to prevent
@@ -76,9 +78,11 @@ elseif lwc.plain or lwc.latex then
         ]],
     }
     lwc.warning = function(str) luatexbase.module_warning(lwc.name, str) end
+    lwc.info = function(str) luatexbase.module_info(lwc.name, str) end
     lwc.attribute = luatexbase.new_attribute(lwc.name)
     lwc.contrib_head = 'contrib_head' -- For \LuaTeX{}
     lwc.stretch_order = "stretch_order"
+    lwc.pagenum = function () return tex.count[0] end
 else -- uh oh
     error [[
         Unsupported format.
@@ -222,20 +226,28 @@ end
 ---
 --- Sometimes the node list can form a loop. Since there is no last element
 --- of a looped linked-list, the `last()` function will never terminate. This
---- function provides a "safe" version of the `last()` function that returns
---- `nil` if the list is circular.
+--- function provides a "safe" version of the `last()` function that will break
+--- the loop at the end if the list is circular.
 local function safe_last(head)
     local ids = {}
+    local prev
 
     while head.next do
         local id = node.is_node(head) -- Returns the internal node id
 
         if ids[id] then
-            lwc.warning("Circular node list detected!")
-            return nil
+            lwc.warning [[Circular node list detected!
+This should never happen. I'll try and recover, but your output may be 
+corrupted. As a workaround, disable lua-widow-control for the
+affected paragraph or change the page breaks in your document.]]
+
+            prev.next = nil
+            return prev
         end
 
         ids[id] = true
+        head.prev = prev
+        prev = head
         head = head.next
     end
 
@@ -265,6 +277,8 @@ function lwc.remove_widows(head)
             return head
     end
 
+    lwc.info("Widow/orphan detected. Attempting to remove.")
+
     local head_save = head -- Save the start of the `head` linked-list
 
     --[[
@@ -296,22 +310,15 @@ function lwc.remove_widows(head)
     while head do
         -- Insert the start of the replacement paragraph
         if has_attribute(head, lwc.attribute, paragraph_index) then
-            local current = head
-            head.prev.next = target_node
-
-            -- Abort if we've created a loop
-            if not safe_last(target_node) then
-                head.prev.next = current
-                lwc.warning("Widow/Orphan NOT removed!")
-                break
-            end
+            safe_last(target_node) -- Remove any loops
 
+            head.prev.next = target_node
             clear_flag = true
         end
 
         -- Insert the end of the replacement paragraph
         if has_attribute(head, lwc.attribute, -1 * paragraph_index) then
-            last(target_node).next = head.next
+            safe_last(target_node).next = head.next
             clear_flag = false
         end
 
@@ -324,6 +331,13 @@ function lwc.remove_widows(head)
             last(head).prev.prev.next = nil
             -- Move the last line to the next page
             tex.lists[lwc.contrib_head] = last_line
+            lwc.info(
+                "Widow/orphan successfully removed at paragraph "
+                .. paragraph_index
+                .. " on page "
+                .. lwc.pagenum()
+                .. "."
+            )
         end
 
         if clear_flag then
diff --git a/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.tex b/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.tex
index a9b236f966b..efab23b8b4b 100644
--- a/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.tex
+++ b/Master/texmf-dist/tex/luatex/lua-widow-control/lua-widow-control.tex
@@ -3,7 +3,14 @@
 % SPDX-License-Identifier: MPL-2.0+
 % SPDX-FileCopyrightText: 2021 Max Chernoff
 
-\wlog{lua-widow-control v1.1.4} %%version
+\wlog{lua-widow-control v1.1.5} %%version
+
+\ifx\directlua\undefined
+    \errmessage{%
+        LuaTeX is required for this package.
+        Make sure to compile with `luatex'%
+    }
+\fi
 
 \input ltluatex % \LuaTeX{}Base