From 30d207d6960a8cdead5b1a240e316f567060d5e7 Mon Sep 17 00:00:00 2001
From: Joseph Wright <joseph.wright@morningstar2.co.uk>
Date: Fri, 6 Jan 2017 10:52:53 +0000
Subject: [PATCH] Patch older and newer versions of beamer code

The fixes in
https://github.com/josephwright/beamer/commit/ef419391cbe5245cabf3b77c89b58023fb253c95
and
https://github.com/josephwright/beamer/commit/ce790e640c0b41ab3adf764a79a9ef9475e37532
mean that a new patch route is needed. Patches cannot be nested
(easily) so use two and a switch to track if an error is needed.
---
 source/beamerfontthememetropolis.dtx | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/source/beamerfontthememetropolis.dtx b/source/beamerfontthememetropolis.dtx
index 5988ca3..09f6212 100644
--- a/source/beamerfontthememetropolis.dtx
+++ b/source/beamerfontthememetropolis.dtx
@@ -367,18 +367,38 @@
   {\def\insertsectionhead{\metropolis@sectiontitleformat{#2}}}
   {}
   {\PackageError{beamerfontthememetropolis}{Patching section title failed}\@ehc}
+\@tempswafalse
 \patchcmd{\beamer@section}
   {\def\insertsectionhead{\hyperlink{Navigation\the\c@page}{#1}}}
   {\def\insertsectionhead{\hyperlink{Navigation\the\c@page}{%
     \metropolis@sectiontitleformat{#1}}}}
+  {\@tempswatrue}
   {}
-  {\PackageError{beamerfontthememetropolis}{Patching section title failed}\@ehc}
+\patchcmd{\beamer@section}
+  {\protected@edef\insertsectionhead{\noexpand\hyperlink{Navigation\the\c@page}{#1}}}
+  {\protected@edef\insertsectionhead{\noexpand\hyperlink{Navigation\the\c@page}{%
+    \noexpand\metropolis@sectiontitleformat{#1}}}}
+  {\@tempswatrue}
+  {}
+\if@tempswa\else
+  \PackageError{beamerfontthememetropolis}{Patching section title failed}\@ehc
+\fi
+\@tempswafalse
 \patchcmd{\beamer@subsection}
   {\def\insertsubsectionhead{\hyperlink{Navigation\the\c@page}{#1}}}
   {\def\insertsubsectionhead{\hyperlink{Navigation\the\c@page}{%
     \metropolis@sectiontitleformat{#1}}}}
+  {\@tempswatrue}
   {}
-  {\PackageError{beamerfontthememetropolis}{Patching section title failed}\@ehc}
+\patchcmd{\beamer@subsection}
+  {\protected@edef\insertsubsectionhead{\noexpand\hyperlink{Navigation\the\c@page}{#1}}}
+  {\protected@edef\insertsubsectionhead{\noexpand\hyperlink{Navigation\the\c@page}{%
+    \noexpand\metropolis@sectiontitleformat{#1}}}}
+  {\@tempswatrue}
+  {}
+\if@tempswa\else
+  \PackageError{beamerfontthememetropolis}{Patching section title failed}\@ehc
+\fi
 %    \end{macrocode}
 %
 % Similarly, to make the |\MakeLowercase| and |\MakeUppercase| macros work in