matrices: Add some tests for & as cell separator.

Include tests for packages: tikz-cd, tikz-dependency, beamer
(deliberately ignoring advice to not use & as cell separator).

Omit dvisvgm result for beamer: it contains complicated dvips specials.

Signed-off-by: Gábor Braun <gabor.braun@uni-duisburg-essen.de>

testfiles/tikzmatrix-beamer.lvt

@@ -0,0 +1,17 @@
+\documentclass{beamer}
+\usepackage{tikz}
+\usetikzlibrary{matrix}
+\input{regression-test}
+
+\begin{document}
+\showoutput
+\START
+\BEGINTEST{Beamer frame: simple matrix}
+\begin{frame}{TikZ matrix test}
+\begin{tikzpicture}
+  \matrix[fill=cyan, draw=red, matrix of nodes]{A & B & C \\ D & E \\};
+\end{tikzpicture}
+\end{frame}
+\ENDTEST
+\END
+\end{document}

testfiles/tikzmatrix-cd.lvt

@@ -0,0 +1,55 @@
+% Test commutative diagrams with tikz-cd.
+\documentclass[tikz]{standalone}
+\usepackage{tikz-cd,amsmath}
+\input{regression-test}
+
+\begin{document}
+\showoutput
+\START
+\BEGINTEST{Matrices in commutative diagram}
+\begin{tikzcd}[/tikz/commutative diagrams/diagrams={column sep=large}]
+  \begin{bmatrix}
+    A_{1} & B_{1} \\
+    A_{2} & B_{2}
+  \end{bmatrix}
+  % The braces are protecting the &, without them it doesn't compile
+  % as of tikz-dependency 1.1.
+  \ar[r, "{\begin{pmatrix} e & f \\ g & h \end{pmatrix}}"]
+  &
+  \begin{bmatrix}
+    C_{1} & D_{1} \\
+    C_{2} & D_{2}
+  \end{bmatrix}
+\end{tikzcd}
+\ENDTEST
+
+\BEGINTEST{Homotopy extension}
+\begin{tikzcd}[row sep=huge, column sep=large]
+  0 \ar[r] & L_{1} \ar[r, "{\begin{bmatrix} 1 & 0 \end{bmatrix}}"]
+  \ar[d, "g"]
+  &
+  \left(
+    L_{1} \oplus K_{1}[1],
+    \begin{bmatrix}
+      \partial_{L_{1}} & 0 \\
+      f_{1} & -\partial_{K_{1}}
+    \end{bmatrix}
+  \right)
+  \ar[r, "{\begin{bmatrix} 0 \\ 1 \end{bmatrix}}"]
+  \ar[d, "{\begin{bmatrix} g & 0 \\ s & h \end{bmatrix}}"]
+  & K_{1}[1] \ar[r] \ar[d, "h"] & 0 \\
+  0 \ar[r] & L_{2} \ar[r, "{\begin{bmatrix} 1 & 0 \end{bmatrix}}"]
+  &
+  \left(
+    L_{2} \oplus K_{2}[1],
+    \begin{bmatrix}
+      \partial_{L_{2}} & 0 \\
+      f_{2} & -\partial_{K_{2}}
+    \end{bmatrix}
+  \right)
+  \ar[r, "{\begin{bmatrix} 0 \\ 1 \end{bmatrix}}"]
+  & K_{2}[1] \ar[r] & 0
+\end{tikzcd}
+\ENDTEST
+\END
+\end{document}