From d14737e2ff267c851851d16406fd5e882e24df0a Mon Sep 17 00:00:00 2001
From: Hironori Kitagawa <h_kitagawa2001@yahoo.co.jp>
Date: Fri, 31 Mar 2023 11:58:33 +0900
Subject: [PATCH] obey \input@path in \[global]{j,t}font (#47723)

---
 src/luatexja-core.sty    | 14 ++++++++++----
 src/luatexja.lua         | 25 +++++++++++++++++--------
 src/patches/lltjfont.sty | 14 ++++++++++++++
 3 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/src/luatexja-core.sty b/src/luatexja-core.sty
index 15d02be..f150faa 100644
--- a/src/luatexja-core.sty
+++ b/src/luatexja-core.sty
@@ -221,11 +221,15 @@
 \luadef\ltj@@start@time@measure\ltj@@start@time@measure@inner
 \luadef\ltj@@stop@time@measure\ltj@@stop@time@measure@inner
 
+\let\ltj@@convert@input@path@to@lua\relax % defined in LaTeX only (ltj-latex.sty)
+
 %%%%%%%% \jfont\CS={...:...;jfm=metric;...}, \globaljfont
 \protected\def\jfont#1{%
-  \def\ltj@temp{#1}\afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(false, 'yoko')}}
+  \ltj@@convert@input@path@to@lua\def\ltj@temp{#1}%
+  \afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(false, 'yoko')}}
 \protected\def\globaljfont#1{%
-  \def\ltj@temp{#1}\afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(true,  'yoko')}}
+  \ltj@@convert@input@path@to@lua\def\ltj@temp{#1}%
+  \afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(true,  'yoko')}}
 \newluafunction\ltj@@jfont@inner
 \directlua{
   (lua.get_functions_table())[\the\ltj@@jfont@inner] = luatexja.jfont.jfontdefY
@@ -234,9 +238,11 @@
 
 %%%%%%%% \tfont\CS={...:...;jfm=metric;...}, \globaltfont
 \protected\def\tfont#1{%
-  \def\ltj@temp{#1}\afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(false, 'tate')}}
+  \ltj@@convert@input@path@to@lua\def\ltj@temp{#1}%
+  \afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(false, 'tate')}}
 \protected\def\globaltfont#1{%
-  \def\ltj@temp{#1}\afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(true,  'tate')}}
+  \ltj@@convert@input@path@to@lua\def\ltj@temp{#1}%
+  \afterassignment\ltj@@jfont\directlua{luatexja.jfont.jfontdefX(true,  'tate')}}
 
 %%%%%%%% \zw, \zh
 \newluafunction\ltj@zw@inner
diff --git a/src/luatexja.lua b/src/luatexja.lua
index 31bd066..64bab4c 100644
--- a/src/luatexja.lua
+++ b/src/luatexja.lua
@@ -1,14 +1,23 @@
 require 'lualibs'
 ------------------------------------------------------------------------
-local function load_lua(fn)
-   local found = kpse.find_file(fn, 'tex')
-   if not found then
-      tex.error("LuaTeX-ja error: File `" .. fn .. "' not found")
-   else
-      texio.write_nl('(' .. found .. ')'); dofile(found)
-   end
+do
+    local ipath = {}
+    function luatexja.input_path_clear() for i in ipairs(ipath) do ipath[i]=nil end end
+    function luatexja.input_path_add(s) ipath[#ipath+1]=s end
+    function luatexja.load_lua(fn)
+        local found = kpse.find_file(fn, 'tex')
+        if not found then
+            for _,v in ipairs(ipath) do
+                found = kpse.find_file(v .. fn, 'tex'); if found then break end
+            end
+        end
+        if not found then
+            tex.error("LuaTeX-ja error: File `" .. fn .. "' not found")
+        else
+            texio.write_nl('(' .. found .. ')'); dofile(found)
+        end
+    end
 end
-luatexja.load_lua = load_lua
 function luatexja.load_module(name) require('ltj-' .. name.. '.lua') end
 
 do
diff --git a/src/patches/lltjfont.sty b/src/patches/lltjfont.sty
index f1435f7..0241243 100644
--- a/src/patches/lltjfont.sty
+++ b/src/patches/lltjfont.sty
@@ -1433,4 +1433,18 @@
   \ltj@@getjfontnumber#1%
   \directlua{luatexja.jfont.pickup_alt_font_b(\the\ltj@tempcntc,'\luatexluaescapestring{#2}')}%
 }
+
+%%%% send \input@path data to lua
+\def\ltj@@convert@input@path@to@lua{%
+  \ltj@@cipath@clear
+  \ifdefined\input@path
+    \@tfor\ltj@temp:=\input@path\do{\ltj@@cipath@add{\ltj@temp}}%
+  \fi
+}
+\newluafunction\ltj@@cipath@clear@inner
+\directlua{
+  (lua.get_functions_table())[\the\ltj@@cipath@clear@inner] = luatexja.input_path_clear
+}
+\protected\luadef\ltj@@cipath@clear\ltj@@cipath@clear@inner
+\def\ltj@@cipath@add#1{\directlua{luatexja.input_path_add('\luatexluaescapestring#1')}}
 \endinput
-- 
2.11.0