[latex3-commits] [git/LaTeX3-latex3-latex2e] mathcolor: Restrict \mathcolor to math mode (8ba77795)

[Frank Mittelbach]

Repository : https://github.com/latex3/latex2e
On branch  : mathcolor
Link       : https://github.com/latex3/latex2e/commit/8ba777959af1fc646b1081c5a279241f1ce2d39f

>---------------------------------------------------------------

commit 8ba777959af1fc646b1081c5a279241f1ce2d39f
Author: Frank Mittelbach <frank.mittelbach at latex-project.org>
Date:   Fri Jan 28 23:28:26 2022 +0100

    Restrict \mathcolor to math mode


>---------------------------------------------------------------

8ba777959af1fc646b1081c5a279241f1ce2d39f
 base/doc/ltnews35.tex                              |  1 +
 required/graphics/changes.txt                      |  2 +-
 required/graphics/mathcolor.dtx                    | 15 +++++++++++---
 required/graphics/testfiles/mathcolor-04.lvt       | 24 ++++++++++++++++++++++
 .../graphics/testfiles/mathcolor-04.tlg            |  4 ++--
 5 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/base/doc/ltnews35.tex b/base/doc/ltnews35.tex
index 98a796df..4c1b910b 100644
--- a/base/doc/ltnews35.tex
+++ b/base/doc/ltnews35.tex
@@ -550,6 +550,7 @@ spacing. Thus, the above example can now be written as
 \begin{verbatim}
 \[ X = \mathcolor{red}{\sum}_{i=1}^n x_i \]
 \end{verbatim}
+This command is \emph{only} allowed in formulas.
 For details and further examples, see \file{mathcolor.pdf}.
 
 
diff --git a/required/graphics/changes.txt b/required/graphics/changes.txt
index 72a106c3..5ec10ab1 100644
--- a/required/graphics/changes.txt
+++ b/required/graphics/changes.txt
@@ -8,7 +8,7 @@ are not part of the distribution.
 
 	* mathcolor.dtx:
 	Support \mathcolor to correctly color parts of formulas without
-	spacing problems.
+	spacing problems. This command is *only* supported in math mode.
 
 ================================================================================
 All changes above are only part of the development branch for the next release.
diff --git a/required/graphics/mathcolor.dtx b/required/graphics/mathcolor.dtx
index 6ed53f8f..cd2ab199 100644
--- a/required/graphics/mathcolor.dtx
+++ b/required/graphics/mathcolor.dtx
@@ -14,8 +14,8 @@
 %%% From File: mathcolor.dtx
 %
 %    \begin{macrocode}
-\def\mathcolorversion{v1.0a}
-\def\mathcolordate{2022/01/07}
+\def\mathcolorversion{v1.0b}
+\def\mathcolordate{2022/01/28}
 %    \end{macrocode}
 %<*driver>
 \documentclass{l3doc}
@@ -165,7 +165,16 @@
 %    \begin{macrocode}
 \DeclareDocumentCommand \mathcolor { o m m } {
 %    \end{macrocode}
-%    First action is to save the current color value on a stack
+%    The \cs{mathcolor} is only supported in math mode because in text
+%    mode it has problems scanning away a space after it, for example.
+%    We therefore raise an error if it executes
+%    anywhere else. The \LaTeXe{} error command is a
+%    bit strangely named, because in the kernel it is only used for
+%    math alphabets, but the message it gives is fine.
+%    \begin{macrocode}
+  \mode_if_math:F { \non at alpherr {\mathcolor\space} }
+%    \end{macrocode}
+%    First real action is to save the current color value on a stack
 %    (needed if the command is nested or contains some further color
 %    changes with \cs{color} inside).
 %    \begin{macrocode}
diff --git a/required/graphics/testfiles/mathcolor-04.lvt b/required/graphics/testfiles/mathcolor-04.lvt
new file mode 100644
index 00000000..c17b98c0
--- /dev/null
+++ b/required/graphics/testfiles/mathcolor-04.lvt
@@ -0,0 +1,24 @@
+
+\documentclass{article}
+
+
+\input{test2e}
+
+\usepackage{color}
+
+
+\begin{document}
+
+\START
+
+% this should give an error, that it then tries typesetting and
+%  usually manages to do something if the argument is not generating
+%  further errors is a side-effect and helps you to carry on.
+
+  \mathcolor{red}{x}
+  
+\END
+
+
+
+
diff --git a/base/testfiles/github-0501.tlg b/required/graphics/testfiles/mathcolor-04.tlg
similarity index 81%
copy from base/testfiles/github-0501.tlg
copy to required/graphics/testfiles/mathcolor-04.tlg
index ee87539b..e0a88557 100644
--- a/base/testfiles/github-0501.tlg
+++ b/required/graphics/testfiles/mathcolor-04.tlg
@@ -1,9 +1,9 @@
 This is a generated file for the LaTeX2e validation system.
 Don't change this file in any respect.
-! LaTeX Error: \mathit allowed only in math mode.
+! LaTeX Error: \mathcolor allowed only in math mode.
 See the LaTeX manual or LaTeX Companion for explanation.
 Type  H <return>  for immediate help.
  ...                                              
-l. ...\mathit{x}
+l. ...  \mathcolor{red}{x}
 You're in trouble here.  Try typing  <return>  to proceed.
 If that doesn't work, type  X <return>  to quit.