2 files changed, 18 insertions, 14 deletions
diff --git a/modules/git/repo_compare.go b/modules/git/repo_compare.go
index 677201c5e0..53b8af4bb4 100644
--- a/modules/git/repo_compare.go
+++ b/modules/git/repo_compare.go
@@ -6,7 +6,6 @@
 package git
 
 import (
-	"bytes"
 	"container/list"
 	"fmt"
 	"io"
@@ -94,19 +93,22 @@ func (repo *Repository) GetCompareInfo(basePath, baseBranch, headBranch string)
 	return compareInfo, nil
 }
 
-// GetPatch generates and returns patch data between given revisions.
-func (repo *Repository) GetPatch(base, head string) ([]byte, error) {
-	return NewCommand("diff", "-p", "--binary", base, head).RunInDirBytes(repo.Path)
+// GetDiffOrPatch generates either diff or formatted patch data between given revisions
+func (repo *Repository) GetDiffOrPatch(base, head string, w io.Writer, formatted bool) error {
+	if formatted {
+		return repo.GetPatch(base, head, w)
+	}
+	return repo.GetDiff(base, head, w)
 }
 
-// GetFormatPatch generates and returns format-patch data between given revisions.
-func (repo *Repository) GetFormatPatch(base, head string) (io.Reader, error) {
-	stdout := new(bytes.Buffer)
-	stderr := new(bytes.Buffer)
+// GetDiff generates and returns patch data between given revisions.
+func (repo *Repository) GetDiff(base, head string, w io.Writer) error {
+	return NewCommand("diff", "-p", "--binary", base, head).
+		RunInDirPipeline(repo.Path, w, nil)
+}
 
-	if err := NewCommand("format-patch", "--binary", "--stdout", base+"..."+head).
-		RunInDirPipeline(repo.Path, stdout, stderr); err != nil {
-		return nil, concatenateError(err, stderr.String())
-	}
-	return stdout, nil
+// GetPatch generates and returns format-patch data between given revisions.
+func (repo *Repository) GetPatch(base, head string, w io.Writer) error {
+	return NewCommand("format-patch", "--binary", "--stdout", base+"..."+head).
+		RunInDirPipeline(repo.Path, w, nil)
 }
diff --git a/modules/git/repo_compare_test.go b/modules/git/repo_compare_test.go
index def67fa87b..bf4631d853 100644
--- a/modules/git/repo_compare_test.go
+++ b/modules/git/repo_compare_test.go
@@ -5,6 +5,7 @@
 package git
 
 import (
+	"bytes"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -21,7 +22,8 @@ func TestGetFormatPatch(t *testing.T) {
 	repo, err := OpenRepository(clonedPath)
 	assert.NoError(t, err)
 	defer repo.Close()
-	rd, err := repo.GetFormatPatch("8d92fc95^", "8d92fc95")
+	rd := &bytes.Buffer{}
+	err = repo.GetPatch("8d92fc95^", "8d92fc95", rd)
 	assert.NoError(t, err)
 	patchb, err := ioutil.ReadAll(rd)
 	assert.NoError(t, err)