plumbing/transport: add common tests and fixes. (#136)

* plumbing/transport: add common tests and fixes.

* add common test suite for different transport implementations.
* fix different behaviour on error handling for ssh and http.
  fixes issue #123.
* support detecting unexisting repositories with SSH + GitHub/Bitbucket
  (apparently, there is no standard for all SSH servers).
* remove ssh.NewClient (only DefaultClient makes sense at the moment).
* make ssh.Client and http.Client private.
* utils/ioutil: utilities to work with io interfaces.

* * transport: test actual objects fetched, not just packfile size.

* * fix doc typo.

* * improve UploadPackRequest.IsEmpty

1 files changed, 166 insertions, 0 deletions

diff --git a/plumbing/transport/test/common.go b/plumbing/transport/test/common.go
new file mode 100644
index 0000000..059c0c9
--- /dev/null
+++ b/plumbing/transport/test/common.go
@@ -0,0 +1,166 @@
+// Package test implements common test suite for different transport
+// implementations.
+//
+package test
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+
+	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
+	"gopkg.in/src-d/go-git.v4/plumbing/transport"
+	"gopkg.in/src-d/go-git.v4/storage/memory"
+
+	. "gopkg.in/check.v1"
+)
+
+type FetchPackSuite struct {
+	Endpoint            transport.Endpoint
+	EmptyEndpoint       transport.Endpoint
+	NonExistentEndpoint transport.Endpoint
+	Client              transport.Client
+}
+
+func (s *FetchPackSuite) TestInfoEmpty(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.EmptyEndpoint)
+	c.Assert(err, IsNil)
+	info, err := r.AdvertisedReferences()
+	c.Assert(err, Equals, transport.ErrEmptyRemoteRepository)
+	c.Assert(info, IsNil)
+}
+
+func (s *FetchPackSuite) TestInfoNotExists(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.NonExistentEndpoint)
+	c.Assert(err, IsNil)
+	info, err := r.AdvertisedReferences()
+	c.Assert(err, Equals, transport.ErrRepositoryNotFound)
+	c.Assert(info, IsNil)
+
+	r, err = s.Client.NewFetchPackSession(s.NonExistentEndpoint)
+	c.Assert(err, IsNil)
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+	reader, err := r.FetchPack(req)
+	c.Assert(err, Equals, transport.ErrRepositoryNotFound)
+	c.Assert(reader, IsNil)
+}
+
+func (s *FetchPackSuite) TestCannotCallAdvertisedReferenceTwice(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	_, err = r.AdvertisedReferences()
+	c.Assert(err, IsNil)
+	_, err = r.AdvertisedReferences()
+	c.Assert(err, Equals, transport.ErrAdvertistedReferencesAlreadyCalled)
+}
+
+func (s *FetchPackSuite) TestDefaultBranch(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	info, err := r.AdvertisedReferences()
+	c.Assert(err, IsNil)
+	c.Assert(info.Capabilities.SymbolicReference("HEAD"), Equals, "refs/heads/master")
+}
+
+func (s *FetchPackSuite) TestCapabilities(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	info, err := r.AdvertisedReferences()
+	c.Assert(err, IsNil)
+	c.Assert(info.Capabilities.Get("agent").Values, HasLen, 1)
+}
+
+func (s *FetchPackSuite) TestFullFetchPack(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	info, err := r.AdvertisedReferences()
+	c.Assert(err, IsNil)
+	c.Assert(info, NotNil)
+
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+
+	reader, err := r.FetchPack(req)
+	c.Assert(err, IsNil)
+
+	s.checkObjectNumber(c, reader, 28)
+}
+
+func (s *FetchPackSuite) TestFetchPack(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+
+	reader, err := r.FetchPack(req)
+	c.Assert(err, IsNil)
+
+	s.checkObjectNumber(c, reader, 28)
+}
+
+func (s *FetchPackSuite) TestFetchPackNoChanges(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+	req.Have(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+
+	reader, err := r.FetchPack(req)
+	c.Assert(err, Equals, transport.ErrEmptyUploadPackRequest)
+	c.Assert(reader, IsNil)
+}
+
+func (s *FetchPackSuite) TestFetchPackMulti(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+	defer func() { c.Assert(r.Close(), IsNil) }()
+
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("6ecf0ef2c2dffb796033e5a02219af86ec6584e5"))
+	req.Want(plumbing.NewHash("e8d3ffab552895c19b9fcf7aa264d277cde33881"))
+
+	reader, err := r.FetchPack(req)
+	c.Assert(err, IsNil)
+
+	s.checkObjectNumber(c, reader, 31)
+}
+
+func (s *FetchPackSuite) TestFetchError(c *C) {
+	r, err := s.Client.NewFetchPackSession(s.Endpoint)
+	c.Assert(err, IsNil)
+
+	req := &transport.UploadPackRequest{}
+	req.Want(plumbing.NewHash("1111111111111111111111111111111111111111"))
+
+	reader, err := r.FetchPack(req)
+	c.Assert(err, Equals, transport.ErrEmptyUploadPackRequest)
+	c.Assert(reader, IsNil)
+
+	//XXX: We do not test Close error, since implementations might return
+	//     different errors if a previous error was found.
+}
+
+func (s *FetchPackSuite) checkObjectNumber(c *C, r io.Reader, n int) {
+	b, err := ioutil.ReadAll(r)
+	c.Assert(err, IsNil)
+	buf := bytes.NewBuffer(b)
+	scanner := packfile.NewScanner(buf)
+	storage := memory.NewStorage()
+	d, err := packfile.NewDecoder(scanner, storage)
+	c.Assert(err, IsNil)
+	_, err = d.Decode()
+	c.Assert(err, IsNil)
+	c.Assert(len(storage.Objects), Equals, n)
+}