Fix binary diffs unable to be viewed in history. Resolves #1650 (#1649)

* Fix binary diffs cause error when viewed
* Change color of git lines to #000000a0
* Update assets

test/test_compare.rb

@@ -0,0 +1,47 @@
+# ~*~ encoding: utf-8 ~*~
+require File.expand_path(File.join(File.dirname(__FILE__), 'helper'))
+require File.expand_path '../../lib/gollum/views/commit', __FILE__
+
+def get_commit_diff(sha1)
+  commit = @wiki.repo.commit(sha1)
+  @wiki.repo.diff(commit.parent.id, sha1)
+end
+
+context "Precious::Views::Compare" do
+  setup do
+    @path    = cloned_testpath('examples/lotr.git')
+    # Precious::App.set(:gollum_path, @path)
+    @wiki = Gollum::Wiki.new(@path)
+  end
+
+  test 'file addition diff' do
+    view = Precious::Views::Compare.new
+    diff = get_commit_diff 'fbabba862dfa7ac35b39042dd4ad780c9f67b8cb'
+    view.instance_variable_set(:@diff, diff)
+
+    assert_equal [
+      {:line=>"@@ -0,0 +1 @@", :class=>"gc", :ldln=>"...", :rdln=>"..."},
+      {:line=>"+# Eye Of Sauron", :class=>"gi", :ldln=>" ", :rdln=>"1"}
+    ], view.lines
+  end
+
+  test 'empty file addition diff' do
+    view = Precious::Views::Compare.new
+    diff = get_commit_diff '181c757cca395d4da18701d069a6b8123e88e040'
+    view.instance_variable_set(:@diff, diff)
+
+    assert_equal [], view.lines
+  end
+
+  test 'binary file addition diff' do
+    view = Precious::Views::Compare.new
+    diff = get_commit_diff 'afe2034d400ba21e13361f38f74900c51dbc7fde'
+    view.instance_variable_set(:@diff, diff)
+
+    lines = view.lines
+    line = lines[0].delete :line
+
+    assert_match %r{Binary files (/dev/null and b/Mordor/eye.jpg )?differ}, line
+    assert_equal [{:class=>"gg", :ldln=>"...", :rdln=>"..."}], lines
+  end
+end