test file for #100 plus minimal (tmp) fix

required/tools/longtable.dtx

@@ -31,7 +31,7 @@
 %<driver> \ProvidesFile{longtable.drv}
 % \fi
 %         \ProvidesFile{longtable.dtx}
-          [2014/10/28 v4.11 Multi-page Table package (DPC)]
+          [2014/10/28 v4.11 Multi-page Table package (DPC)+ FMi change]
 %
 % \iffalse
 %<*driver>
@@ -2100,6 +2100,8 @@
 %    \begin{macrocode}
 \def\LT@startpbox#1{%
   \bgroup
+%FMi
+  \color@begingroup
     \let\@footnotetext\LT@p@ftntext
     \setlength\hsize{#1}%
     \@arrayparboxrestore
@@ -2120,6 +2122,8 @@
 %    \begin{macrocode}
 \def\LT@endpbox{%
   \@finalstrut\@arstrutbox
+%FMi
+  \color@endgroup 
   \egroup
   \the\LT@p@ftn
   \global\LT@p@ftn{}%

required/tools/testfiles/github-0100.lvt

@@ -0,0 +1,47 @@
+% https://github.com/latex3/latex2e/issues/100
+%
+% no color leak please
+
+\documentclass{article}
+
+ % Any preamble code goes here
+\usepackage{color}
+\usepackage{array}         % [=2018-04-01] that version still correct
+\usepackage{longtable}
+
+\input{test2e}
+
+\showoutput
+
+\begin{document}
+
+\START
+
+% Demonstration of issue here
+Fine: tabular, 1st column is fixed width and should be blue\newline
+\begin{tabular}{>{\color{blue}}m{2.5cm} c }
+one & two \\
+three & four \\
+\end{tabular}\newline
+Note that text afterwards is still black
+
+\vspace{6ex}
+
+Fine: longtable,1st column is NOT fixed width and should be blue
+\begin{longtable}{>{\color{blue}}c c }\endhead
+one & two \\
+three & four \\
+\end{longtable}
+Note that text afterwards is still black
+
+\vspace{6ex}
+
+Problem: longtable,1st column is fixed width and should be blue
+\begin{longtable}{>{\color{blue}}m{2.5cm} c }\endhead
+one & two \\
+three & four \\
+\end{longtable}
+Note that the text in all the columns, and the text afterwards, is blue!
+
+\end{document}
+