pkg/vcs: expose commit patch

Add Commit.Patch with patch body.

3 files changed, 34 insertions, 2 deletions

diff --git a/pkg/vcs/git.go b/pkg/vcs/git.go
index dd1681157..7425066d2 100644
--- a/pkg/vcs/git.go
+++ b/pkg/vcs/git.go
@@ -242,11 +242,25 @@ func (git *git) Contains(commit string) (bool, error) {
 }
 
 func (git *git) Commit(com string) (*Commit, error) {
-	output, err := git.git("log", "--format=%H%n%s%n%ae%n%an%n%ad%n%P%n%cd%n%b", "-n", "1", com)
+	const patchSeparator = "---===syzkaller-patch-separator===---"
+	output, err := git.git("log", "--format=%H%n%s%n%ae%n%an%n%ad%n%P%n%cd%n%b"+patchSeparator,
+		"-n", "1", "-p", "-U0", com)
 	if err != nil {
 		return nil, err
 	}
-	return gitParseCommit(output, nil, nil, git.ignoreCC)
+	pos := bytes.Index(output, []byte(patchSeparator))
+	if pos == -1 {
+		return nil, fmt.Errorf("git log output does not contain patch separator")
+	}
+	commit, err := gitParseCommit(output[:pos], nil, nil, git.ignoreCC)
+	if err != nil {
+		return nil, err
+	}
+	commit.Patch = output[pos+len(patchSeparator):]
+	for len(commit.Patch) != 0 && commit.Patch[0] == '\n' {
+		commit.Patch = commit.Patch[1:]
+	}
+	return commit, nil
 }
 
 func gitParseCommit(output, user, domain []byte, ignoreCC map[string]bool) (*Commit, error) {
diff --git a/pkg/vcs/git_test.go b/pkg/vcs/git_test.go
index 8ff4dbb6e..a46408417 100644
--- a/pkg/vcs/git_test.go
+++ b/pkg/vcs/git_test.go
@@ -316,6 +316,23 @@ func TestObject(t *testing.T) {
 	if diff := cmp.Diff(data, secondRev); diff != "" {
 		t.Fatal(diff)
 	}
+	com, err := repo.repo.Commit(commits[0])
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	patch := []byte(`diff --git a/object.txt b/object.txt
+index 103167d..fbf7a68 100644
+--- a/object.txt
++++ b/object.txt
+@@ -1 +1 @@
+-First revision
+\ No newline at end of file
++Second revision
+\ No newline at end of file
+`)
+	if diff := cmp.Diff(com.Patch, patch); diff != "" {
+		t.Fatal(diff)
+	}
 }
 
 func TestMergeBase(t *testing.T) {
diff --git a/pkg/vcs/vcs.go b/pkg/vcs/vcs.go
index 369765b0e..17f54d653 100644
--- a/pkg/vcs/vcs.go
+++ b/pkg/vcs/vcs.go
@@ -117,6 +117,7 @@ type Commit struct {
 	Parents    []string
 	Date       time.Time
 	CommitDate time.Time
+	Patch      []byte
 }
 
 type RecipientType int