CI: adjust to clang-format-10 automatically

- leave clang-format file alone, but dynamically
  modify it when clang-format 10 or later is present
- ignore the resulting .bak file

.gitignore

@@ -50,6 +50,7 @@ CMakeLists.txt.user
 
 # Backup files
 *~
+*.bak
 
 # Kate
 *.kate-swp

ci/calamaresstyle

@@ -35,7 +35,13 @@ test -n "$CF" || { echo "! No clang-format ($CF_VERSIONS) found in PATH"; exit 1
 test -x "$AS" || { echo "! $AS is not executable."; exit 1 ; }
 test -x "$CF" || { echo "! $CF is not executable."; exit 1 ; }
 
-expr `"$CF" --version | tr -dc '[^.0-9]' | cut  -d . -f 1` '<' 10 > /dev/null ||  { echo "! $CF is version 10 or later, needs different .clang-format" ; exit 1 ; }
+unmangle_clang_format=""
+if expr `"$CF" --version | tr -dc '[^.0-9]' | cut  -d . -f 1` '<' 10 > /dev/null ; then
+	:
+else
+	unmangle_clang_format=$( dirname $0 )/../.clang-format
+	echo "SpaceInEmptyBlock: false" >> "$unmangle_clang_format"
+fi
 
 set -e
 
@@ -65,3 +71,7 @@ if test "x$any_dirs" = "xyes" ; then
 else
 	style_some "$@"
 fi
+
+if test -n "$unmangle_clang_format" ; then
+	sed -i.bak '/^SpaceInEmptyBlock/d' "$unmangle_clang_format"
+fi