move plumbing from top level package to plumbing (#183)

* plumbing: rename Object -> EncodedObject.

* plumbing/storer: rename ObjectStorer -> EncodedObjectStorer.

* move difftree to plumbing/difftree.

* move diff -> utils/diff

* make Object/Tag/Blob/Tree/Commit/File depend on storer.

* Object and its implementations now depend only on
  storer.EncodedObjectStorer, not git.Repository.
* Tests are decoupled accordingly.

* move Object/Commit/File/Tag/Tree to plumbing/object.

* move Object/Commit/File/Tag/Tree to plumbing/object.
* move checkClose to utils/ioutil.

* move RevListObjects to plumbing/revlist.Objects.

* move DiffTree to plumbing/difftree package.

* rename files with plural nouns to singular

* plumbing/object: add GetBlob/GetCommit/GetTag/GetTree.

1 files changed, 199 insertions, 0 deletions

diff --git a/plumbing/object/object_test.go b/plumbing/object/object_test.go
new file mode 100644
index 0000000..04f2b73
--- /dev/null
+++ b/plumbing/object/object_test.go
@@ -0,0 +1,199 @@
+package object
+
+import (
+	"io"
+	"io/ioutil"
+	"testing"
+	"time"
+
+	"gopkg.in/src-d/go-git.v4/fixtures"
+	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/plumbing/storer"
+	"gopkg.in/src-d/go-git.v4/storage/filesystem"
+
+	. "gopkg.in/check.v1"
+)
+
+func Test(t *testing.T) { TestingT(t) }
+
+type BaseObjectsSuite struct {
+	fixtures.Suite
+	Storer  storer.EncodedObjectStorer
+	Fixture *fixtures.Fixture
+}
+
+func (s *BaseObjectsSuite) SetUpSuite(c *C) {
+	s.Suite.SetUpSuite(c)
+	s.Fixture = fixtures.Basic().One()
+	storer, err := filesystem.NewStorage(s.Fixture.DotGit())
+	c.Assert(err, IsNil)
+	s.Storer = storer
+}
+
+func (s *BaseObjectsSuite) tag(c *C, h plumbing.Hash) *Tag {
+	t, err := GetTag(s.Storer, h)
+	c.Assert(err, IsNil)
+	return t
+}
+
+func (s *BaseObjectsSuite) tree(c *C, h plumbing.Hash) *Tree {
+	t, err := GetTree(s.Storer, h)
+	c.Assert(err, IsNil)
+	return t
+}
+
+func (s *BaseObjectsSuite) commit(c *C, h plumbing.Hash) *Commit {
+	commit, err := GetCommit(s.Storer, h)
+	c.Assert(err, IsNil)
+	return commit
+}
+
+type ObjectsSuite struct {
+	BaseObjectsSuite
+}
+
+var _ = Suite(&ObjectsSuite{})
+
+func (s *ObjectsSuite) TestNewCommit(c *C) {
+	hash := plumbing.NewHash("a5b8b09e2f8fcb0bb99d3ccb0958157b40890d69")
+	commit := s.commit(c, hash)
+
+	c.Assert(commit.Hash, Equals, commit.ID())
+	c.Assert(commit.Hash.String(), Equals, "a5b8b09e2f8fcb0bb99d3ccb0958157b40890d69")
+
+	tree, err := commit.Tree()
+	c.Assert(err, IsNil)
+	c.Assert(tree.Hash.String(), Equals, "c2d30fa8ef288618f65f6eed6e168e0d514886f4")
+
+	parents := commit.Parents()
+	parentCommit, err := parents.Next()
+	c.Assert(err, IsNil)
+	c.Assert(parentCommit.Hash.String(), Equals, "b029517f6300c2da0f4b651b8642506cd6aaf45d")
+
+	parentCommit, err = parents.Next()
+	c.Assert(err, IsNil)
+	c.Assert(parentCommit.Hash.String(), Equals, "b8e471f58bcbca63b07bda20e428190409c2db47")
+
+	c.Assert(commit.Author.Email, Equals, "mcuadros@gmail.com")
+	c.Assert(commit.Author.Name, Equals, "Máximo Cuadros")
+	c.Assert(commit.Author.When.Format(time.RFC3339), Equals, "2015-03-31T13:47:14+02:00")
+	c.Assert(commit.Committer.Email, Equals, "mcuadros@gmail.com")
+	c.Assert(commit.Message, Equals, "Merge pull request #1 from dripolles/feature\n\nCreating changelog")
+}
+
+func (s *ObjectsSuite) TestParseTree(c *C) {
+	hash := plumbing.NewHash("a8d315b2b1c615d43042c3a62402b8a54288cf5c")
+	tree, err := GetTree(s.Storer, hash)
+	c.Assert(err, IsNil)
+
+	c.Assert(tree.Entries, HasLen, 8)
+
+	tree.buildMap()
+	c.Assert(tree.m, HasLen, 8)
+	c.Assert(tree.m[".gitignore"].Name, Equals, ".gitignore")
+	c.Assert(tree.m[".gitignore"].Mode.String(), Equals, "-rw-r--r--")
+	c.Assert(tree.m[".gitignore"].Hash.String(), Equals, "32858aad3c383ed1ff0a0f9bdf231d54a00c9e88")
+
+	count := 0
+	iter := tree.Files()
+	defer iter.Close()
+	for f, err := iter.Next(); err == nil; f, err = iter.Next() {
+		count++
+		if f.Name == "go/example.go" {
+			reader, err := f.Reader()
+			c.Assert(err, IsNil)
+			defer func() { c.Assert(reader.Close(), IsNil) }()
+			content, _ := ioutil.ReadAll(reader)
+			c.Assert(content, HasLen, 2780)
+		}
+	}
+
+	c.Assert(count, Equals, 9)
+}
+
+func (s *ObjectsSuite) TestParseSignature(c *C) {
+	cases := map[string]Signature{
+		`Foo Bar <foo@bar.com> 1257894000 +0100`: {
+			Name:  "Foo Bar",
+			Email: "foo@bar.com",
+			When:  MustParseTime("2009-11-11 00:00:00 +0100"),
+		},
+		`Foo Bar <foo@bar.com> 1257894000 -0700`: {
+			Name:  "Foo Bar",
+			Email: "foo@bar.com",
+			When:  MustParseTime("2009-11-10 16:00:00 -0700"),
+		},
+		`Foo Bar <> 1257894000 +0100`: {
+			Name:  "Foo Bar",
+			Email: "",
+			When:  MustParseTime("2009-11-11 00:00:00 +0100"),
+		},
+		` <> 1257894000`: {
+			Name:  "",
+			Email: "",
+			When:  MustParseTime("2009-11-10 23:00:00 +0000"),
+		},
+		`Foo Bar <foo@bar.com>`: {
+			Name:  "Foo Bar",
+			Email: "foo@bar.com",
+			When:  time.Time{},
+		},
+		``: {
+			Name:  "",
+			Email: "",
+			When:  time.Time{},
+		},
+		`<`: {
+			Name:  "",
+			Email: "",
+			When:  time.Time{},
+		},
+	}
+
+	for raw, exp := range cases {
+		got := &Signature{}
+		got.Decode([]byte(raw))
+
+		c.Assert(got.Name, Equals, exp.Name)
+		c.Assert(got.Email, Equals, exp.Email)
+		c.Assert(got.When.Format(time.RFC3339), Equals, exp.When.Format(time.RFC3339))
+	}
+}
+
+func (s *ObjectsSuite) TestObjectIter(c *C) {
+	encIter, err := s.Storer.IterEncodedObjects(plumbing.AnyObject)
+	c.Assert(err, IsNil)
+	iter := NewObjectIter(s.Storer, encIter)
+
+	objects := []Object{}
+	iter.ForEach(func(o Object) error {
+		objects = append(objects, o)
+		return nil
+	})
+
+	c.Assert(len(objects) > 0, Equals, true)
+	iter.Close()
+
+	encIter, err = s.Storer.IterEncodedObjects(plumbing.AnyObject)
+	c.Assert(err, IsNil)
+	iter = NewObjectIter(s.Storer, encIter)
+
+	i := 0
+	for {
+		o, err := iter.Next()
+		if err == io.EOF {
+			break
+		}
+
+		c.Assert(err, IsNil)
+		c.Assert(o, DeepEquals, objects[i])
+		i += 1
+	}
+
+	iter.Close()
+}
+
+func MustParseTime(value string) time.Time {
+	t, _ := time.Parse("2006-01-02 15:04:05 -0700", value)
+	return t
+}