4 files changed, 52 insertions, 4 deletions
diff --git a/Build/source/texk/web2c/Makefile.in b/Build/source/texk/web2c/Makefile.in
index a417f4de475..6a93f4430cb 100644
--- a/Build/source/texk/web2c/Makefile.in
+++ b/Build/source/texk/web2c/Makefile.in
@@ -5337,7 +5337,10 @@ call_luajithbtex_LDADD =
 
 # LuaTeX/LuaJITTeX Tests
 #
-luatex_tests = luatexdir/luatex.test luatexdir/luaimage.test
+luatex_tests = luatexdir/luatex.test luatexdir/luaimage.test \
+               luatexdir/luaoutputdir.test
+
+#
 luahbtex_tests = luatexdir/luatex.test luatexdir/luaimage.test
 luajittex_tests = luatexdir/luajittex.test luatexdir/luajitimage.test
 luajithbtex_tests = luatexdir/luajittex.test luatexdir/luajitimage.test
@@ -22324,7 +22327,8 @@ $(luajithbtex_OBJECTS): libluajittex.a
 @MINGW32_FALSE@@WIN32_TRUE@uninstall-luajithbtex-links:
 @MINGW32_FALSE@@WIN32_TRUE@	rm -f $(DESTDIR)$(bindir)/texluajit$(EXEEXT)
 @MINGW32_FALSE@@WIN32_TRUE@	rm -f $(DESTDIR)$(bindir)/texluajitc$(EXEEXT)
-luatexdir/luatex.log luatexdir/luaimage.log: luatex$(EXEEXT)
+luatexdir/luatex.log luatexdir/luaimage.log luatexdir/luaoutputdir.log: \
+  luatex$(EXEEXT)
 luatexdir/luahbtex.log luatexdir/luahbimage.log: luahbtex$(EXEEXT)
 luatexdir/luajittex.log luatexdir/luajitimage.log: luajittex$(EXEEXT)
 luatexdir/luajithbtex.log luatexdir/luajithbimage.log: luajithbtex$(EXEEXT)
diff --git a/Build/source/texk/web2c/luatexdir/ChangeLog b/Build/source/texk/web2c/luatexdir/ChangeLog
index f182f16e4c5..3fef4a3a73a 100644
--- a/Build/source/texk/web2c/luatexdir/ChangeLog
+++ b/Build/source/texk/web2c/luatexdir/ChangeLog
@@ -1,3 +1,9 @@
+2023-10-04  Karl Berry  <karl@freefriends.org>
+
+	* luaoutputdir.test: new test for Lua-level reading from a given
+	--output-directory.
+	* am/luatex.am (luatex_tests): add it, plus .log dependency.
+
 2023-04-29  Luigi Scarso <luigi.scarso@gmail.com> 
     * LuaTeX 1.17.0
 
diff --git a/Build/source/texk/web2c/luatexdir/am/luatex.am b/Build/source/texk/web2c/luatexdir/am/luatex.am
index 93333ba587f..32feab1105b 100644
--- a/Build/source/texk/web2c/luatexdir/am/luatex.am
+++ b/Build/source/texk/web2c/luatexdir/am/luatex.am
@@ -232,8 +232,11 @@ endif WIN32
 
 # LuaTeX/LuaJITTeX Tests
 #
-luatex_tests = luatexdir/luatex.test luatexdir/luaimage.test
-luatexdir/luatex.log luatexdir/luaimage.log: luatex$(EXEEXT)
+luatex_tests = luatexdir/luatex.test luatexdir/luaimage.test \
+               luatexdir/luaoutputdir.test
+luatexdir/luatex.log luatexdir/luaimage.log luatexdir/luaoutputdir.log: \
+  luatex$(EXEEXT)
+#
 luahbtex_tests = luatexdir/luatex.test luatexdir/luaimage.test
 luatexdir/luahbtex.log luatexdir/luahbimage.log: luahbtex$(EXEEXT)
 
diff --git a/Build/source/texk/web2c/luatexdir/luaoutputdir.test b/Build/source/texk/web2c/luatexdir/luaoutputdir.test
new file mode 100755
index 00000000000..c9b3b3e0729
--- /dev/null
+++ b/Build/source/texk/web2c/luatexdir/luaoutputdir.test
@@ -0,0 +1,35 @@
+#! /bin/sh -vx
+# luaoutputdir.test - check that Lua-level kpse.* reads from -output-directory.
+# Public domain. Originally written by Karl Berry, 2023.
+# https://github.com/latex3/latex3/issues/1070
+
+BinDir=${BinDir:-.} # ordinarily run from the web2c builddir
+ExeExt=${ExeExt:-}
+_luatex=$BinDir/luatex$ExeExt
+
+# in case we're invoked standalone instead of from make.
+test -z "$srcdir" && srcdir=`cd \`dirname $0\`/.. && pwd` # web2c/
+TEXMFCNF=$srcdir/../kpathsea; export TEXMFCNF
+
+outdir=tests/outdirlua
+outfile=outfileLUA.tex
+rm -rf $outdir  # don't let previous runs interfere
+mkdir $outdir || exit 1
+
+$_luatex -ini -output-directory=$outdir '\immediate\openout1='$outfile'\end' \
+|| exit 3
+
+ls -l $outdir/$outfile || exit 7
+
+# Then we should be able to read it back in TeX.
+$_luatex -ini -output-directory=$outdir '\input '$outfile' \end' || exit 9
+
+# And we should also be able to read it back in Lua.
+$_luatex -ini -output-directory=$outdir \
+'\catcode123=1 \catcode125=2
+ \directlua{local file=kpse.find_file("'$outfile'");
+            if (file == nil) then os.exit(1); end}
+ \end
+' || exit 11
+
+exit 0