From ca958f74d6a97471bd6e5f8ed0eb3872fc3dcf77 Mon Sep 17 00:00:00 2001
From: Glenn Rice <grice1@missouriwestern.edu>
Date: Thu, 6 Nov 2025 08:34:29 -0600
Subject: [PATCH] Add a standalone variant to check_latex.

The packages and TikZ libraries that are used by pg are all tested
(including the TikZ spath library that is going to be used once
https://github.com/openwebwork/pg/pull/1336 is merged).

Note that the "active" option was removed from the preview package in
the check_latex_article.tex and check_latex_exam.tex files because that
suppresses output.  It is enough to test that the preview package loads,
and this makes the more important things that are being tested more like
they are for actual hardcopy generation and not for equation generation.
We really need to remove images mode.
---
 bin/check_latex                |  8 +++++---
 bin/check_latex_article.tex    |  2 +-
 bin/check_latex_exam.tex       |  2 +-
 bin/check_latex_standalone.tex | 22 ++++++++++++++++++++++
 4 files changed, 29 insertions(+), 5 deletions(-)
 create mode 100644 bin/check_latex_standalone.tex

diff --git a/bin/check_latex b/bin/check_latex
index 8c5a6ee567..a806cea296 100755
--- a/bin/check_latex
+++ b/bin/check_latex
@@ -13,8 +13,8 @@ use feature 'say';
 
 BEGIN {
 	use Mojo::File qw(curfile);
-	use YAML::XS qw(LoadFile);
-	use Env qw(WEBWORK_ROOT PG_ROOT);
+	use YAML::XS   qw(LoadFile);
+	use Env        qw(WEBWORK_ROOT PG_ROOT);
 
 	$WEBWORK_ROOT = curfile->dirname->dirname->to_string;
 
@@ -51,7 +51,9 @@ my $latex_cmd =
 	. shell_quote($ce->{webworkDirs}{assetsTex}) . ':'
 	. shell_quote($ce->{pg}{directories}{assetsTex}) . ': '
 	. $ce->{externalPrograms}{latex2pdf}
-	. ' -interaction nonstopmode check_latex_exam.tex >> check_latex.nfo 2>&1';
+	. ' -interaction nonstopmode check_latex_exam.tex >> check_latex.nfo 2>&1 &&'
+	. "TEXINPUTS=$ENV{WEBWORK_ROOT}/bin: $ce->{externalPrograms}{latex2pdf}"
+	. ' -interaction nonstopmode check_latex_standalone.tex > check_latex.nfo 2>&1';
 
 if ((system $latex_cmd) >> 8) {
 	if (open(my $fh, '<', "$temp_dir/check_latex.nfo")) {
diff --git a/bin/check_latex_article.tex b/bin/check_latex_article.tex
index 76036857ee..21d58de3e6 100644
--- a/bin/check_latex_article.tex
+++ b/bin/check_latex_article.tex
@@ -8,7 +8,7 @@
 \usepackage{multicol}
 \usepackage{tcolorbox}
 
-\usepackage[active,textmath,displaymath]{preview}  % needed for dvipng
+\usepackage[textmath,displaymath]{preview}  % needed for dvipng
 
 \setlength{\columnsep}{.25in}
 \setlength{\columnseprule}{.4pt}
diff --git a/bin/check_latex_exam.tex b/bin/check_latex_exam.tex
index bd48c01ef5..384a8ba693 100644
--- a/bin/check_latex_exam.tex
+++ b/bin/check_latex_exam.tex
@@ -9,7 +9,7 @@
   \usepackage{bidi}
 \fi
 
-\usepackage[active,textmath,displaymath]{preview}  % needed for dvipng
+\usepackage[textmath,displaymath]{preview}  % needed for dvipng
 
 \setlength{\columnsep}{.25in}
 \setlength{\columnseprule}{.4pt}
diff --git a/bin/check_latex_standalone.tex b/bin/check_latex_standalone.tex
new file mode 100644
index 0000000000..7f8daeecd6
--- /dev/null
+++ b/bin/check_latex_standalone.tex
@@ -0,0 +1,22 @@
+\documentclass{standalone}
+
+\usepackage[svgnames]{xcolor}
+\usepackage{tikz}
+\usepackage{pgfplots}
+\usetikzlibrary{arrows.meta,plotmarks,calc,spath3}
+\usepgfplotslibrary{fillbetween}
+\pgfplotsset{compat = 1.18}
+
+\begin{document}
+
+\begin{tikzpicture}
+	\begin{axis}
+		\addplot[name path=pathA, domain=-3:3, draw=none, mark=triangle*] {(x^2)};
+		\draw[{Stealth}-{Stealth}, spath/use=pathA];
+		\draw ($(-1, 0) + (10pt, 10pt)$) -- ($(1, 3) - (10pt, 10pt)$);
+		\addplot[name path=pathB, domain=-3:3] {(-x^2 + 3)};
+		\addplot[green, fill opacity=0.3] fill between[of=pathA and pathB];
+	\end{axis}
+\end{tikzpicture}
+
+\end{document}