git: add benchmark for iterating repository objects

Signed-off-by: Miguel Molina <miguel@erizocosmi.co>

Author: erizocosmico

repository_test.go

@@ -1688,3 +1688,59 @@ func (s *RepositorySuite) TestBrokenMultipleShallowFetch(c *C) {
 	})
 	c.Assert(err, IsNil)
 }
+
+func BenchmarkObjects(b *testing.B) {
+	if err := fixtures.Init(); err != nil {
+		b.Fatal(err)
+	}
+
+	defer func() {
+		if err := fixtures.Clean(); err != nil {
+			b.Fatal(err)
+		}
+	}()
+
+	for _, f := range fixtures.ByTag("packfile") {
+		if f.DotGitHash == plumbing.ZeroHash {
+			continue
+		}
+
+		b.Run(f.URL, func(b *testing.B) {
+			fs := f.DotGit()
+			storer, err := filesystem.NewStorage(fs)
+			if err != nil {
+				b.Fatal(err)
+			}
+
+			worktree, err := fs.Chroot(filepath.Dir(fs.Root()))
+			if err != nil {
+				b.Fatal(err)
+			}
+
+			repo, err := Open(storer, worktree)
+			if err != nil {
+				b.Fatal(err)
+			}
+
+			for i := 0; i < b.N; i++ {
+				iter, err := repo.Objects()
+				if err != nil {
+					b.Fatal(err)
+				}
+
+				for {
+					_, err := iter.Next()
+					if err == io.EOF {
+						break
+					}
+
+					if err != nil {
+						b.Fatal(err)
+					}
+				}
+
+				iter.Close()
+			}
+		})
+	}
+}