add method for getting the reverse diff without a page path

lib/gollum/wiki.rb

@@ -580,7 +580,7 @@ module Gollum
 
     # Creates a reverse diff for the given SHAs on the given Gollum::Page.
     #
-    # page   - The Gollum::Page to scope the patch to.
+    # page   - The Gollum::Page to scope the patch to, or a String Path.
     # sha1   - String SHA1 of the earlier parent if two SHAs are given,
     #          or the child.
     # sha2   - Optional String SHA1 of the child.
@@ -588,7 +588,22 @@ module Gollum
     # Returns a String of the reverse Diff to apply.
     def full_reverse_diff_for(page, sha1, sha2 = nil)
       sha1, sha2 = "#{sha1}^", sha1 if sha2.nil?
-      repo.git.native(:diff, {:R => true}, sha1, sha2, '--', page.path)
+      args = [{:R => true}, sha1, sha2]
+      if page
+        args << '--' << (page.respond_to?(:path) ? page.path : page.to_s)
+      end
+      repo.git.native(:diff, *args)
+    end
+
+    # Creates a reverse diff for the given SHAs.
+    #
+    # sha1   - String SHA1 of the earlier parent if two SHAs are given,
+    #          or the child.
+    # sha2   - Optional String SHA1 of the child.
+    #
+    # Returns a String of the reverse Diff to apply.
+    def full_reverse_diff(sha1, sha2 = nil)
+      full_reverse_diff_for(nil, sha1, sha2)
     end
 
     # Ensures a commit hash has all the required fields for a commit.

test/test_wiki.rb

@@ -61,30 +61,6 @@ context "Wiki" do
       @wiki.normalize_commit(commit.dup))
   end
 
-  #test "#tree_map_for caches ref and tree" do
-  #  assert @wiki.ref_map.empty?
-  #  assert @wiki.tree_map.empty?
-  #  @wiki.tree_map_for 'master'
-  #  assert_equal({"master"=>"60f12f4254f58801b9ee7db7bca5fa8aeefaa56b"}, @wiki.ref_map)
-  #
-  #  map = @wiki.tree_map['60f12f4254f58801b9ee7db7bca5fa8aeefaa56b']
-  #  assert_equal 'Bilbo-Baggins.md',        map[0].path
-  #  assert_equal '',                        map[0].dir
-  #  assert_equal map[0].path,               map[0].name
-  #  assert_equal 'Mordor/Eye-Of-Sauron.md', map[3].path
-  #  assert_equal '/Mordor',                 map[3].dir
-  #  assert_equal 'Eye-Of-Sauron.md',        map[3].name
-  #end
-  #
-  #test "#tree_map_for only caches tree for commit" do
-  #  assert @wiki.tree_map.empty?
-  #  @wiki.tree_map_for '60f12f4254f58801b9ee7db7bca5fa8aeefaa56b'
-  #  assert @wiki.ref_map.empty?
-  #
-  #  entry = @wiki.tree_map['60f12f4254f58801b9ee7db7bca5fa8aeefaa56b'][0]
-  #  assert_equal 'Bilbo-Baggins.md', entry.path
-  #end
-
   test "text_data" do
     wiki = Gollum::Wiki.new(testpath("examples/yubiwa.git"))
     if String.instance_methods.include?(:encoding)
@@ -97,6 +73,19 @@ context "Wiki" do
       assert_equal page.raw_data, page.text_data
     end
   end
+
+  test "gets reverse diff" do
+    diff = @wiki.full_reverse_diff('a8ad3c09dd842a3517085bfadd37718856dee813')
+    assert_match "b/Mordor/_Sidebar.md", diff
+    assert_match "b/_Sidebar.md", diff
+  end
+
+  test "gets reverse diff for a page" do
+    diff  = @wiki.full_reverse_diff_for('_Sidebar.md', 'a8ad3c09dd842a3517085bfadd37718856dee813')
+    regex = /b\/Mordor\/\_Sidebar\.md/
+    assert_match    "b/_Sidebar.md", diff
+    assert_no_match regex, diff
+  end
 end
 
 context "Wiki page previewing" do