Get commit diff using "git diff" instead of comparing files of trees manually

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Gemfile.lock

 PATH
   remote: .
   specs:
-    gitlab-grit (2.6.8)
+    gitlab-grit (2.6.9)
       charlock_holmes (~> 0.6)
       diff-lcs (~> 1.1)
       mime-types (~> 1.15)

History.txt

+== 2.6.9
+  * Fix commit diff issue. It shows empty diff for commit when files have changed mode
+
 == 2.6.8
   * Fix problem with generating archives

VERSION

-2.6.8
+2.6.9

lib/grit/commit.rb

@@ -146,7 +146,7 @@ module Grit
         # GITLAB patch
         # Skip all garbage unless we get real commit
         while !lines.empty? && lines.first !~ /^commit [a-zA-Z0-9]*$/
-          lines.shift 
+          lines.shift
         end
         id = lines.shift.split.last
@@ -214,8 +214,8 @@ module Grit
         diff = @repo.git.show({:full_index => true, :pretty => 'raw'}, @id)
       end
-      if diff =~ /diff --git "?a/
-        diff = diff.sub(/.+?(diff --git "?a)/m, '\1')
+      if diff =~ /diff --git a/
+        diff = diff.sub(/.*?(diff --git a)/m, '\1')
       else
         diff = ''
       end
@@ -228,11 +228,7 @@ module Grit
     #
     # Returns Grit::Diff[] (baked)
     def diffs(options = {})
-      if parents.empty?
-        show
-      else
-        self.class.diff(@repo, parents.first.id, @id, [], options)
-      end
+      show
     end
     def stats

test/test_commit.rb

@@ -91,7 +91,7 @@ class TestCommit < Test::Unit::TestCase
   def test_diffs
     # git diff --full-index 91169e1f5fa4de2eaea3f176461f5dc784796769 > test/fixtures/diff_p
-    Git.any_instance.expects(:diff).returns(fixture('diff_p'))
+    Git.any_instance.expects(:native).returns(fixture('diff_p'))
     @c = Commit.create(@r, :id => '91169e1f5fa4de2eaea3f176461f5dc784796769')
     diffs = @c.diffs
@@ -150,7 +150,7 @@ class TestCommit < Test::Unit::TestCase
   end
   def test_diffs_with_mode_only_change
-    Git.any_instance.expects(:diff).returns(fixture('diff_mode_only'))
+    Git.any_instance.expects(:native).returns(fixture('diff_mode_only'))
     @c = Commit.create(@r, :id => '91169e1f5fa4de2eaea3f176461f5dc784796769')
     diffs = @c.diffs
@@ -160,11 +160,7 @@ class TestCommit < Test::Unit::TestCase
   end
   def test_diffs_with_options
-    Git.any_instance.expects(:diff).
-      with({:full_index => true, :M => true},
-        '038af8c329ef7c1bae4568b98bd5c58510465493',
-        '91169e1f5fa4de2eaea3f176461f5dc784796769').
-      returns(fixture('diff_mode_only'))
+    Git.any_instance.expects(:native).returns(fixture('diff_mode_only'))
     @c = Commit.create(@r, :id => '91169e1f5fa4de2eaea3f176461f5dc784796769')
     @c.diffs :M => true
   end