add revert action

lib/gollum/frontend/app.rb

@@ -82,6 +82,30 @@ module Precious
       end
     end
 
+    post '/revert/:page/*' do
+      wiki  = Gollum::Wiki.new(settings.gollum_path)
+      @name = params[:page]
+      @page = wiki.page(@name)
+      shas  = params[:splat].first.split("/")
+      sha1  = shas.shift
+      sha2  = shas.shift
+      sha1  = "#{sha1}^" if sha2
+
+      if wiki.revert_page(@page, sha1, sha2, commit_message)
+        redirect "/#{CGI.escape(@name)}"
+      else
+        if sha2
+          sha1.chomp!('^')
+        else
+          sha2, sha1 = sha1, "#{sha1}^"
+        end
+        @versions = [sha1, sha2]
+        diffs     = wiki.repo.diff(@versions.first, @versions.last, @page.path)
+        @diff     = diffs.first
+        mustache :compare
+      end
+    end
+
     post '/preview' do
       wiki     = Gollum::Wiki.new(settings.gollum_path)
       @name    = "Preview"

test/test_app.rb

@@ -97,6 +97,43 @@ context "Frontend" do
     assert last_response.ok?
   end
 
+  test "reverts single commit" do
+    page1 = @wiki.page('B')
+
+    post "/revert/B/7c45b5f16ff3bae2a0063191ef832701214d4df5"
+    follow_redirect!
+    assert last_response.ok?
+
+    @wiki.clear_cache
+    page2 = @wiki.page('B')
+    assert_not_equal page1.version.sha, page2.version.sha
+    assert_equal "INITIAL", page2.raw_data.strip
+  end
+
+  test "reverts multiple commits" do
+    page1 = @wiki.page('A')
+
+    post "/revert/A/302a5491a9a5ba12c7652ac831a44961afa312d2/b26b791cb7917c4f37dd9cb4d1e0efb24ac4d26f"
+    follow_redirect!
+    assert last_response.ok?
+
+    @wiki.clear_cache
+    page2 = @wiki.page('A')
+    assert_not_equal page1.version.sha, page2.version.sha
+    assert_equal "INITIAL", page2.raw_data.strip
+  end
+
+  test "cannot revert conflicting commit" do
+    page1 = @wiki.page('A')
+
+    post "/revert/A/302a5491a9a5ba12c7652ac831a44961afa312d2"
+    assert last_response.ok?
+
+    @wiki.clear_cache
+    page2 = @wiki.page('A')
+    assert_equal page1.version.sha, page2.version.sha
+  end
+
   def app
     Precious::App
   end