Fix commit.File() gorutine leak

Commit.File() was leaking a goroutine because it was looping over
an iterator without closing its channel.

Now commit.File() calls the new Tree.File() method that searches
the file in the repository by trasversing the dir tree instead
of using the tree.Files() iterator.

This not only prevent the goroutine leak, but also speeds up
file searching.

1 files changed, 134 insertions, 0 deletions

diff --git a/tree_test.go b/tree_test.go
new file mode 100644
index 0000000..049161c
--- /dev/null
+++ b/tree_test.go
@@ -0,0 +1,134 @@
+package git
+
+import (
+	"os"
+
+	"gopkg.in/src-d/go-git.v2/core"
+	"gopkg.in/src-d/go-git.v2/formats/packfile"
+
+	. "gopkg.in/check.v1"
+)
+
+type SuiteTree struct {
+	repos map[string]*Repository
+}
+
+var _ = Suite(&SuiteTree{})
+
+// create the repositories of the fixtures
+func (s *SuiteTree) SetUpSuite(c *C) {
+	fixtureRepos := [...]struct {
+		url      string
+		packfile string
+	}{
+		{"https://github.com/tyba/git-fixture.git", "formats/packfile/fixtures/git-fixture.ofs-delta"},
+		{"https://github.com/cpcs499/Final_Pres_P.git", "formats/packfile/fixtures/Final_Pres_P.ofs-delta"},
+		{"https://github.com/jamesob/desk.git", "formats/packfile/fixtures/jamesob-desk.pack"},
+		{"https://github.com/spinnaker/spinnaker.git", "formats/packfile/fixtures/spinnaker-spinnaker.pack"},
+		{"https://github.com/alcortesm/binary-relations.git", "formats/packfile/fixtures/alcortesm-binary-relations.pack"},
+	}
+	s.repos = make(map[string]*Repository, 0)
+	for _, fixRepo := range fixtureRepos {
+		s.repos[fixRepo.url] = NewPlainRepository()
+
+		d, err := os.Open(fixRepo.packfile)
+		c.Assert(err, IsNil)
+
+		r := packfile.NewReader(d)
+		r.Format = packfile.OFSDeltaFormat // TODO: how to know the format of a pack file ahead of time?
+
+		_, err = r.Read(s.repos[fixRepo.url].Storage)
+		c.Assert(err, IsNil)
+
+		c.Assert(d.Close(), IsNil)
+	}
+}
+
+func (s *SuiteTree) TestFile(c *C) {
+	for i, t := range []struct {
+		repo     string // the repo name as in localRepos
+		commit   string // the commit to search for the file
+		path     string // the path of the file to find
+		blobHash string // expected hash of the returned file
+		found    bool   // expected found value
+	}{
+		// use git ls-tree commit to get the hash of the blobs
+		{"https://github.com/tyba/git-fixture.git", "b029517f6300c2da0f4b651b8642506cd6aaf45d", "not-found",
+			"", false},
+		{"https://github.com/tyba/git-fixture.git", "b029517f6300c2da0f4b651b8642506cd6aaf45d", ".gitignore",
+			"32858aad3c383ed1ff0a0f9bdf231d54a00c9e88", true},
+		{"https://github.com/tyba/git-fixture.git", "b029517f6300c2da0f4b651b8642506cd6aaf45d", "LICENSE",
+			"c192bd6a24ea1ab01d78686e417c8bdc7c3d197f", true},
+
+		{"https://github.com/tyba/git-fixture.git", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5", "not-found",
+			"", false},
+		{"https://github.com/tyba/git-fixture.git", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5", ".gitignore",
+			"32858aad3c383ed1ff0a0f9bdf231d54a00c9e88", true},
+		{"https://github.com/tyba/git-fixture.git", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5", "binary.jpg",
+			"d5c0f4ab811897cadf03aec358ae60d21f91c50d", true},
+		{"https://github.com/tyba/git-fixture.git", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5", "LICENSE",
+			"c192bd6a24ea1ab01d78686e417c8bdc7c3d197f", true},
+
+		{"https://github.com/tyba/git-fixture.git", "35e85108805c84807bc66a02d91535e1e24b38b9", "binary.jpg",
+			"d5c0f4ab811897cadf03aec358ae60d21f91c50d", true},
+		{"https://github.com/tyba/git-fixture.git", "b029517f6300c2da0f4b651b8642506cd6aaf45d", "binary.jpg",
+			"", false},
+
+		{"https://github.com/tyba/git-fixture.git", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", true},
+		{"https://github.com/tyba/git-fixture.git", "1669dce138d9b841a518c64b10914d88f5e488ea", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", true},
+		{"https://github.com/tyba/git-fixture.git", "a5b8b09e2f8fcb0bb99d3ccb0958157b40890d69", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", true},
+		{"https://github.com/tyba/git-fixture.git", "35e85108805c84807bc66a02d91535e1e24b38b9", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", false},
+		{"https://github.com/tyba/git-fixture.git", "b8e471f58bcbca63b07bda20e428190409c2db47", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", true},
+		{"https://github.com/tyba/git-fixture.git", "b029517f6300c2da0f4b651b8642506cd6aaf45d", "CHANGELOG",
+			"d3ff53e0564a9f87d8e84b6e28e5060e517008aa", false},
+
+		// git submodule
+		{"https://github.com/cpcs499/Final_Pres_P.git", "70bade703ce556c2c7391a8065c45c943e8b6bc3", "Final",
+			"", false},
+		{"https://github.com/cpcs499/Final_Pres_P.git", "70bade703ce556c2c7391a8065c45c943e8b6bc3", "Final/not-found",
+			"", false},
+
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "LICENSE",
+			"49c45e6cc893d6f5ebd5c9343fe4492360f339bf", true},
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "examples",
+			"", false},
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "examples/desk.sh",
+			"d9c7751138824cd2d539c23d5afe3f9d29836854", true},
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "examples/not-found",
+			"", false},
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "test/bashrc",
+			"e69de29bb2d1d6434b8b29ae775ad8c2e48c5391", true},
+		{"https://github.com/jamesob/desk.git", "d4edaf0e8101fcea437ebd982d899fe2cc0f9f7b", "test/not-found",
+			"", false},
+
+		{"https://github.com/spinnaker/spinnaker.git", "b32b2aecae2cfca4840dd480f8082da206a538da", "etc/apache2/sites-available/spinnaker.conf",
+			"1d452c616be4fb16d2cc6b8a7e7a2208a6e64d2d", true},
+
+		{"https://github.com/alcortesm/binary-relations.git", "c44b5176e99085c8fe36fa27b045590a7b9d34c9", "Makefile",
+			"2dd2ad8c14de6612ed15813679a6554bad99330b", true},
+		{"https://github.com/alcortesm/binary-relations.git", "c44b5176e99085c8fe36fa27b045590a7b9d34c9", "src/binrels",
+			"", false},
+		{"https://github.com/alcortesm/binary-relations.git", "c44b5176e99085c8fe36fa27b045590a7b9d34c9", "src/map-slice",
+			"", false},
+		{"https://github.com/alcortesm/binary-relations.git", "c44b5176e99085c8fe36fa27b045590a7b9d34c9", "src/map-slice/map-slice.go",
+			"12431e98381dd5097e1a19fe53429c72ef1f328e", true},
+		{"https://github.com/alcortesm/binary-relations.git", "c44b5176e99085c8fe36fa27b045590a7b9d34c9", "src/map-slice/map-slice.go/not-found",
+			"", false},
+	} {
+		commit, err := s.repos[t.repo].Commit(core.NewHash(t.commit))
+		c.Assert(err, IsNil, Commentf("subtest %d: %v (%s)", i, err, t.commit))
+
+		tree := commit.Tree()
+		file, err := tree.File(t.path)
+		found := err == nil
+		c.Assert(found, Equals, t.found, Commentf("subtest %d, path=%s, commit=%s", i, t.path, t.commit))
+		if found {
+			c.Assert(file.Hash.String(), Equals, t.blobHash, Commentf("subtest %d, commit=%s, path=%s", i, t.commit, t.path))
+		}
+	}
+}