Get rid of trailing space.

Makefile

@@ -62,4 +62,4 @@ mo:
 test:
 	@rm -f tests/individually-importing/*.py # To avoid stray files
 	python scripts/gen_individual_importing_tests.py
-	runprove tests/board_gen/*.py tests/individually-importing/*.py
+	runprove tests/style/*.t tests/board_gen/*.py tests/individually-importing/*.py

pysollib/images.py

@@ -72,7 +72,7 @@ class Images:
         self._pil_shadow = {}           # key: (width, height)
         self._highlight = []            # highlight of card (tip)
         self._highlight_index = 0       #
-        self._highlighted_images = {}    # key: (suit, rank)
+        self._highlighted_images = {}   # key: (suit, rank)
 
     def destruct(self):
         pass

tests/style/style-trailing-space.t

@@ -0,0 +1,29 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More;
+
+eval "use Test::TrailingSpace";
+if ($@)
+{
+    plan skip_all => "Test::TrailingSpace required for trailing space test.";
+}
+else
+{
+    plan tests => 1;
+}
+
+my $finder = Test::TrailingSpace->new(
+    {
+        root => '.',
+        filename_regex => qr/(?:(?:\.(?:t|pm|pl|PL|yml|json|arc|vim|py|tcl))|README|Changes|LICENSE|MANIFEST|AUTHORS|COPYING)\z/,
+    },
+);
+
+# TEST
+$finder->no_trailing_space(
+    "No trailing space was found."
+);
+